Lithium (from Greek: λίθος, translate. lithos, lit. ‘stone’) is a chemical element with symbol Li and atomic number 3. It is a soft, silvery-white alkali metal.
Under standard conditions, it is the lightest metal and the lightest solid element. Like all alkali metals, lithium is highly reactive and flammable, and is stored in mineral oil.
When cut, it exhibits a metallic luster, but moist air corrodes it quickly to a dull silvery gray, then black tarnish.
It never occurs freely in nature, but only in (usually ionic) compounds, such as pegmatitic minerals, which were once the main source of lithium.
Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.


Lithium is a soft, the lightest, silver-white, highly reactive metallic element in Group 1 of periodic table; atomic number 3; atomic mass 6.941; melting point ca 180.5 C; boiling point ca 1,342 C; specific gravity 0.534 g/cm3 valence +1; electronic config. 2-1 or 1s 22s 1. Lithium metal is prepared by the electrolysis of a molten mixture of potassium and lithium chlorides.

It is used in various alloys with magnesium, copper, manganese, cadmium and aluminum to form a strong, low density material,as a heat transfer medium, in cooling system of nuclear reactor, and as a scavenger, in ceramics, glasses and in rocket fuel.
Lithium forms many important inorganic and organic compounds such as;

Li. Hydride (LiH):

Flammable, white, translucent solids; decomposes at 850 °C; reacts violently with water to yield hydrogen and lithium hydroxide; used as a hydrogen source or reducing agent to prepare other hydrides amides and 2H isotopic compound, as a shielding material for thermal neutrons.

Lithium Hydroxide (LiOH); white, hygroscopic, crystalline material; soluble in water, slightly soluble in ethanol and insoluble in ether; there are commercially forms of mono hydrate and anhydrous;

used for purification of gases and air (as a carbon dioxide absorbent), as a heat transfer medium, as a storage-battery electrolyte, as a catalyst for polymerization, in ceramics, manufacturing other lithium compounds and esterification specially for lithium stearate which is used as general purpose lubricating greases due to its high resistance to water and the useful at both high and low temperature.

white granular powder; slight soluble in water, melts at 723°C, decomposes above 1310°C; It is prepared commercially by treating the ore with sulphuric acid at 250°C and leaching the product to give a solution of lithium sulphate.
The carbonate is then obtained by precipitation with sodium carbonate solution; It is used as a flux in the aluminum, glass and ceramics production to improves the brightness of glazes and increases the firing range.
It is a source of Lithia, strong high temperature flux.
It is used as an additive in cement industry to improve acceleration and fast setting process.
It is used as an additive in floor screeds and tiles.
It is used for the production of other lithium chemicals and organic compounds as a catalyst.
Pharmaceutical grade of lithium carbonate is used for the primary treatment of depression and bipolar disordez

Li.Bromide (LiBr);

white powder with a bitter taste; melts at 547°C,soluble in water, alcohol and glycol;
used as an operating medium for air-conditioning and industrial drying system due to its very hygroscopic property.
and as a sedative and hypnotic in medicine.
It is also used in manufacturing pharmaceuticals and alkylation process. It is used as brazing and welding fluxes.
Lithium chloride; white hygroscopic deliquescent granule or powder having high melting point at 614°C.
Lithium chloride and bromide are the mostly periscopic materials used as an operating medium for air-conditioning and industrial drying system. It is used as brazing and welding fluxes. It is also used in as an intermediate for manufacturing other chemical compounds.

Li.Fluoride (LiF);

white poisonous powder melting at 870°C, boiling at 1670°C; slightly soluble in water, soluble in acids but insoluble in alcohol; t is used as a flux in the aluminum, glass and ceramics production to improves the brightness of glazes and increases the firing range. It is used as a flux for brazing and welding of zirconium, titanium and magnesium. It is used as a heat-exchange medium.
Lithium Iodide (LiI; LiI.3H2O) white to yellowish solid; soluble in water alcohol; there are commercially anhydrous form (melts at 446°C) and trihydrate form (loses water at 72°C); It is used in organic synthesis, manufacturing medicines and mineral waters.

Li. Stearate (LiC18H35O2);

white crystalline powder derived from lithium hydroxide with cooking tallow (or other animal fat); melting at 220 C; used as general purpose lubricating greases providing high resistance to water and the useful at both high and low temperature, which have found extensive applications in the automotive, aircraft and heavy machinery industry. It is also applied as a stabilizer in cosmetics as well as plastic industry. It is used as a corrosion inhibitor in petroleum.

Li. Molybdate (Li2MoO4);

white crystals melting at 705°C; soluble in water; used as a catalyst for petroleum cracking and as a mill additive for steel.
Lithia (Li2O); A white crystalline compound, melting at 1700°C. the main uses are in lubricating greases, ceramics, glass and refractories, and as a flux in brazing and welding.

Li. Carbide (Li2C2);
Li. Phosphate (Li3PO4);
Li. Sulphate (Li2SO4);

white crystalline material, soluble in water but insoluble in ethanol. It forms a mono-hydrate and an anhydrous form, the compound is prepared by the reaction of the hydroxide or carbonate with sulphuric acid. Lithium Tetrahydridoaluminate (Lithal, LiAlH4); A powerful reducing agent in synthetic organic chemistry; aldehydes, esters and ketones to the corresponding alcohols. nitriles to primary amines.

caustic soda flakes
caustic soda flakes

Caustic soda  flakes

Caustic soda  flakes : Caustic Soda Lye is one of the most widely used chemicals
in the industry.
Caustic soda is a solution of Sodium hydroxide (NAOH) in water.
It is a strong base with a wide range of applications in different industries.
We produce caustic soda with  chlorine and hydrogen from the electrolysis
of salt brine.

With our production in four plants in Europe and our quality commitment,
we guarantee a high service level towards our customers.

Worldwide, the major users of caustic soda are the aluminum industry,
pulp & paper and the chemical industry.

The main applications are water treatment and water purification,
combination as cleaning agent,
or a wide range of uses in chemical industry like starch production or
for the desulphurization in the petrochemical industry.

Caustic soda is obtained from the electrolysis of salt.
A concentrated solution of purified salt (Na-Cl) in demineralized water (i.e. brine)
is decomposed in an electrolytic cell by the passage of an electrical current (DC).

In the electrolytic cell, the sodium chloride solution is decomposed to chlorine at
the anode and to a sodium hydroxide solution and hydrogen at the cathode.


  • water demineralization: regeneration of ion ex changers
  • drinking water production: partial water softening
  • beverages: bottle-cleaning
  • dairy: cleaning production installations
  • rayon industry: preparation of spinning solutions
  • pharmaceutical industry: various products, including sodium lactate
  • cooking oils and fats: refining and purification
  • production of starches and derivatives
  • petroleum industry: refining and desulfurization
  • waste-water treatment: pH-correction, flocculants enhancers
  • steel production: ammonia recovery in cokes production

Arax chemistry industry group


ARAX CHEMISTRY industrial group, great, manufacturer of Caustic Soda flakes
with high quality,

world-class packaging, the price-appropriate and up to date rate
is ready to provide any service to domestic and foreign customers.

contact us:

+98912 930 1051

+98912 930 1052

The best manufacturer of caustic soda flakes
The best manufacturer of caustic soda flakes

The best manufacturer of caustic soda flakes
The best producer of caustic soda : Arax Chemistry Co. as one of the largest
producer of caustic soda uses the new production line and utilizes the production
of liquid sodium hydroxide in the form of update technology
has been producing this product with membrane electrolyzes and in a perfectly
principled manner.
The company’s activities include the production of solid sodium hydroxide 98% in
triple-layer bags (polyethylene and Polypropylene and a plastic inner layer)
and metal buckets, which are for use in all industries Including the production of
detergents and factories for the production of paper and vegetable oil and dairy products and refineries
And petrochemicals and ……. It is produced.

It acts as an intermediate and reactive process in which many substances,
including solvents, Plastics, Synthetic fibers, Bleaching agents, Adhesives,
Coatings, Inks, Paints, Herbicides and Materials
A drug such as aspirin is produced, used.
Caustic soda is also used in the oil and gas industry, ceramic industry,
the neutralization of acidic water
And cleaning and removing acid compounds from exhaust gases.

Hence, this chemical is one of the most widely used chemicals in the industry.
Important points in this factory is the high quality of the product and the standard
packaging of it.

The Arax Chemical Industry Group has issued a major share of its products to
foreign markets And, in line with national production, supports domestic
consumers and the domestic market This product covers.

Stay in touch with us

To get caustic soda, contact Arax Chiemi’s consultants and experts
Get your product in the shortest possible time and at the most affordable price.

What is soda ash?
What is soda ash?

What is soda ash?

What is soda ash? Sodium carbonate (Na2CO3) called soda ash,
Soda crystals and washing soda are also known.
One of the most important industrial chemicals that is widely used
in the production of other alkali products
, Sodium salts and … are used.
Soda ash is the common name for sodium carbonate without water,
which is used industrially.
Sodium carbonate or its sodium hydroxide, in fact,
is sodium salts of carbonic acid,
which is normally in the form of Solid white.
Sodium carbonate on an industrial scale through the process of sowing
and using ammonia, limestone, and salt is produced.
One of the most important uses of sodium carbonate is in the glass industry.
Sodium carbonate has a relatively strong alkaline property and can be
extracted from the ash of many plants.

Physical and Chemical Properties of Sodium Carbonate

The melting point of sodium carbonate is 851 degrees Celsius.
This product decomposes at higher temperatures. So the boiling temperature
for this substance is not defined.
The solubility of sodium carbonate in water at 20 ° C is 215 g / l.

Physical Characteristics of carbonate

Sodium carbonate reacts with carbon dioxide and water to produce
bicarbonate sodium.
Na2CO3 + CO2 + H2O → 2NaHCO3
Sodium bicarbonate produces sodium carbonate in the presence of sodium.
NaHCO3 + NaOH → Na2CO3 + H2O
The dissolution of sodium carbonate in water is a heat-reactive reaction.
For industrial applications, two types of sodium carbonate are used

• Heavy sodium carbonate
• Light Sodium Carbonate

The difference between heavy sodium carbonate and light sodium carbonate
is in density, particle size and application They are not chemically distinct.
Heavy sodium carbonate The mass density is about 1000 kg / m3 and particle
size 300-500 Micron
This kind of carbonate is often used in glass factories.
The larger particles of this kind of granule cause the absence of dust and
impurities and probability
Reduces particle flux during transport.
The density of sodium carbonate is about 500 kg / m3 and the size of sodium
carbonate’s component is about 100 microns.
Lightweight sodium carbonate is used to produce chemicals and detergents.

Application of sodium carbonate

Sodium carbonate is one of the most widely used materials in various industries.
Among the uses of sodium carbonate (soda ash), we can mention the following.

Glass manufacturing: Sodium carbonate is used in the glass industry.
The use of this material in glass can reduce the glass formation temperature
and save energy.

Production of chemicals: Sodium carbonate in the production of various chemicals
such as sodium bicarbonate, sodium Silicate, Sodium Triple Phosphate,
Sodium Dichromate, Sodium Aluminate, Sodium Cyanide. . . is used.

Paper production: In the industry, sodium carbonate paper is used as a
stabilizing agent for acidity, as well as for stripping of waste paper.

• Soap and detergent production: Its use in the production of soap and detergents
is used as alkali.

Water softening: Sodium carbonate in the ion exchange process removes
calcium and magnesium ions from the water and reduces its hardness.

• Urban Water Tanks: Soda ash, as a common additive in urban reservoirs,
is used to neutralize the acidic effect of chlorine and to increase ph.

• Home Appliance:

Sodium carbonate is used in homes as a water softener in the washing of clothes.
It resists magnesium ions and calcium in hard water and prevents the bond
formation They are used with detergent.
Without the use of sodium carbonate, an additional detergent is needed to
soak up magnesium ions and calcium Gets

• Dyeing: It is used as a bonding agent between colors and fibers.

• Food industry: As pH regulator and preservative.

• Electrolysis: As an electrolyte, it increases the rate of water decomposition.

Taxidermy: The process of removing meat from bones is used.

• Chemistry labs are used as the primary standard in titration reactions.

• Toothpaste: As a pH-enhancing agent, the flooring agent is used.

• Brick Making: As a wetting agent in the production of dough,
it reduces the amount of water used.

• Textile Industry: Used as an anti-acid agent in silk processing.

Petrochemicals and Crude Petroleum Refining: It is used as neutralizing in petrochemical processes.

• Purification of vegetable oils: acts as a free fatty acid separator.

• Smoke from smoke: In the process of sulfur removal, smoke from the flue is used.

Raw materials required for the production of sodium carbonate

The raw materials required to produce sodium carbonate by Solvay are limestone,
Normal salts and ammonia produced by the reaction of sodium carbonate below.

CaCO3 → CO2 + CaO

2NH3 + CO2 + H2O → (NH4) 2CO3

(NH4) 2CO3 + CO2 + H2O → 2NH4HCO3

NH4HCO3 + NaCl → NaHCO3 + NH4Cl

2NaHCO3 → Na2CO3 + CO2 + H2O

Classification of chemicals
Classification of chemicals

Classification of chemicals

Classification of chemicals: Dangerous goods are classified and labeled
in many countries according to the United Nations system.
In this system, hazardous goods are categorized according to their hazardous properties in six classes.
These classes include nine distinct classes and a different class of materials.
The risks for each class are marked with special rhomboidal labels.
Some hazardous goods, including classes 8, 4, 1, 2 and 9, have sub-classes.
Which indicates a certain aspect of the dangers of the substance.
In some classes, subsequent categorization includes packaging groups
, which indicates the relative risk of matter inside a class
(PG-III low risk, PG-II medium risk, high-risk PGI)
Therefore, all packages, containers, and tankers carrying hazardous goods should
be labeled appropriately with the appropriate class name.
This label shows the nature of the risk using a color system and special characters,
as well as a hazard class item.

Class 1 Explosive

class 1

Includes substances that can cause explosions or pyrotechnic effects.
Production of explosives is generally limited and is subject to the relevant regulations.
The use of explosives for research needs is subject to obtaining the necessary permissions from the responsible organizations.

Explosives include 6 sub-classes:

Class 1-1 Explosives with a sudden and fearful explosion
Example: TNT Nitroglycerin, Mercury Fulminate

Class 1-2 Explosives with Risk of Throw (but not the danger of a blast of fearsome)
Example: bombs, grenades

Class 1-3 Explosive materials with a high fire hazard
Example: gunpowder, fireworks

Class 1-4 Explosives without fearsome explosion
Example: Fireworks on Toys

Classes 1-5 Explosive explosives with low explosive sensitivity
Depower like Proprietary Example: Explosive

Class 1-6 Explosive materials with very low explosive sensitivity

Class 2 gases

class 2

The hazardous goods of this class include pressure gases, liquid gases or pressure gases.

Gases include 3 sub-classes:

Class 2-1 flammable gases

Class 2-2 Non-flammable and non-toxic gases

Class 2-3 toxic gases

Toxic gases are gases that inhale them to cause death or serious health damage to humans.

Example: chlorine and ammonia.

Class 3 flammable liquids
class 3

For liquids flammable, a mixture of liquids or liquids containing solids is soluble or suspended.

Which can ignite in contact with a source of ignition, such as gasoline, thinners, paints, varnishes and flammable solvents?

It should be noted that in the older segmentation of this class, two sub-scales were divided into two sub-classes: 0-2 and 0-1.

But the new classification for subclass flammable liquids has not been taken into
consideration, but for these materials, the packaging groups (PG I, II, III) have been

PGI grade 3 – Highly flammable liquid
With an initial boiling point less than 08 ° C

Example: Di-ethyl ether, carbon disulfide

Class PG-II -3 Flammable Liquids Extremely high
With an initial boiling point greater than 08 ° C and a flash point less than
10 ° C

Like: gasoline, acetone

Class PIROGI -3 flammable liquid with flash point 10 to 92 ° C

Example: Crown, Turpentine Mineral

This group was called “subclass 2-3” in the previous division

Class 4 flammable solids

class 4

Hazardous materials in this class include materials with spontaneous combustion
potential as well as materials that can cause flammable gases in contact with water.
Also, solids (other than explosives) that immediately burn or cause fire are also classified in this class.

This class contains 3 sub-classes:

Class 4-1 flammable liquid

Materials that are easily ignited and combustible.
Example: Nitrocellulose, phosphorus, matches, and Acid Pic

Class 4-2 cylinders with spontaneous combustion potential
Example: Charcoal, cotton and white phosphorus

Class 4 – Dangerous substances in the wet state
Includes solids that create flammable gases in contact with water.
Example: aluminum phosphide and calcium carbide

Class 5 oxidizing substances

class 5

The oxidizing agent contains 2 sub-classes:

Class 5-1 Oxidizing agents (other than organic peroxides)

Like hydrogen peroxide, calcium hypochlorite (used in pools), ammonium nitrate and nitrates

Class 5-2 Organic peroxides (solid or liquid)

Examples: Methyl Ethyl Ketone Peroxide, Benzoyl Peroxide, Di benzoyl, and Per
Acetic Acid.
Oxidizing substances are not necessarily combustible by themselves but may cause other materials to ignite.
For example, sodium peroxide in the presence of water creates a strongly exothermic reaction,
and the need for mixing with charcoal also causes spontaneous combustion.
Organic peroxides have a structure with bivalent oxygen.

These materials are thermal insecure materials and therefore may spontaneously
decompose, which can sometimes cause explosive reactions or burn quickly,
or be sensitive to impact or friction, or produce dangerous reactions with other materials

Class 6 Toxic and Infectious Substances

class 6


This class includes two sub-classes of toxic substances and infectious substances,
but toxic gases, previously classified in class 3-2, are not included in this class.

Class 6-1: Toxic substances (including liquids and toxic solids)

Toxic substances include substances that cause death or serious injury
and serious harm to humans if swallowed, inhaled or through skin contact.

Example: Sodium Cyanide (NaCN) Cyanides and Arsenic Compounds.

Class 6-2 Infectious agents

Substances are substances that are known to be infectious or possibly
pathogenic (microorganisms include bacteria, viruses, rickettsia, parasites, and fungi).
Vaccines and pathological specimens are examples of this.
The maintenance instructions, how to work and how to dispose of infectious
substances should be in accordance with the health regulations and the
mode of transportation of this group of materials subject to the provisions
of environmental protection

Class 7 radioactive substances

This class contains materials or materials that constantly emit radioactive contaminants.
More precisely, the radioactive substance is a substance with a specific activity greater than 70 KB q / kg.
The activity is specific to activity in a unit mass of a radioactive substance.
There are no sub-classes for this class, but different packing groups are considered.
Example: Radioisotopes and uranium

Class 8 corrosives

class 8
Corrosive materials are solid or liquid substances that can damage the living tissues
and equipment during contact with chemical agents.

In other words, corrosive substances are substances that, by chemical action,
cause severe damage to living tissues, equipment, and other materials.

Examples: Hydrofluoric Acid,


, and Clay Pools.

Class 9 Miscellaneous materials

class 9
This class shows the risk of miscellaneous materials that are not particularly severe
and are not classified in other classes.

Such as intense magnetic materials, aerosols, ammonium nitrate fertilizers,
and polyester granules.

Dangerous goods labels

This label represents various classes of hazardous goods and is used when
shipping these goods.

Why caustic soda?
Why caustic soda?

Why caustic soda?

Why caustic soda? Sodium hydroxide as a highly reactive alkali is widely used in various industries.

Caustic soda has a faster and stronger reactivity than other alkali materials.

This material does not produce adverse effects such as carbon dioxide or other carbonates during chemical processes.

Caustic soda can be used for pulp and paper industry, aluminum production,

Ink-removing waste paper, water purification and disinfectants.

Caustic soda is the primary substance in the production of many chemicals.

This substance is used as an intermediate and reactive process in which
many materials are made up of solvents, plastics, synthetic fibers,
bleaching agents, adhesives, coatings, inks, paints,
herbicides and pharmaceuticals such as aspirin.

Caustic soda is also used for the soap and construction of detergents, oil and gas industries,

The ceramic industry is used to neutralize acidic wastewater and to clean and
remove acidic compounds from exhaust gases.

so, this chemical is one of the most used chemicals in the industry.

Usages of sodium hydroxide

Chemical production:

In the chemical industry, about 40% of the produced caustic soda is used as a
base material for the production of many chemicals.

Detergent and disinfectant products:

Caustic soda is used for the production of soap and detergents with various
household and industrial applications.
Chlorine bleaching solutions (bleaching agents containing chlorine such as sodium
hypochlorite) are obtained from the combination of chlorine and caustic soda.
Tubes that contain caustic soda,
By converting fats and oil materials that have the potential for blockage of pipes
and water and sewage routes,
Water soluble materials prevent blockage of the pipes.

Medical and Pharmaceutical:

Caustic soda in the production of many pharmaceutical and medical substances
from simple painkillers, such as aspirin, to anticoagulants that can prevent blood coagulation and
It is used in steroidal anti-arrhythmic drugs.

pulp and paper production:

Sulfate and sulfite pulp produced by purification of lignin compounds using
multiple units extracted by liquid caustic soda are purified.
Also, in some factories that use the craft process to produce paper,
Liquid sodium hydroxide is used.
In addition to the usages of caustic soda, in the paper industry,
this chemical isThe Initial removal of ink from recycled paper.

cellophane and silk:

The production of fibers using the viscose process requires two main steps needs caustic soda.
Cellulose is used to enhance the strength and shine, resulting in the production
of alkaline cellulose by the liquor of treated liquid,
The resulting cellulose is then dissolved in the diluted liquid extract to produce
viscose material used to extrude silk fibers and cellophane films.

Aluminum extraction:

The use of caustic soda in the aluminum industry is used to dissolve bauxite ore,
which is the primary material for the production of aluminum,
and the deposition of aluminum?
Caustic soda is also used for chemical brushes of aluminum products.

Soap making:

The caustic soda converts fats into water-soluble soaps.
the cloth:
In this industry, caustic soda is used to clean, whiten and enhance the shine
and toughness of the cloth.

Oil production and refining industry:

Caustic Soda as a carbon dioxide absorber in lightweight cuts
As sulfide adsorbent, it is used to purify various oil cuts.
Also, caustic soda along with chlorine for the hypochlorite
sweetening process that is a process for
The removal of various sulfur compounds is applicable.

Sodium carbonate substitute (soda ash):

Caustic soda is used as an alternative to its hydrate in many applications in the glass
paper, pulp, phosphate and silicate industries.

Food Production:

Sodium hydroxide is used in the production and processing of several nutrients.
Such as the use of caustic soda in the processing of olive or in the process of producing woody salty to create brittle.
The fruit is used to separate the peel of potatoes, tomatoes and other fruits for canning.
Also, caustic soda is used to prevent the growth of bacteria and mildew in certain foods and to prevent their corrosion.

Water and Sewage Treatment:

In water and wastewater treatment plants, water utilization is used to control
the acidity of water and help remove heavy metals from water.
Also, the caustic soda is in the production of sodium hypochlorite (bleach),
which is an antiseptic.


The use of caustic soda is used in the production of fuel cells.
In the manufacture of epoxy resins, which are used in wind turbines,
Caustic soda is used.

Nonrenewable fuels:

Caustic soda is used to adjust the pH and produce sodium methyl’s in the
bio-ethanol and biodiesel production process.

Chemical pollutants
Chemical pollutants

Chemical pollutants

Chemical pollutants are divided into organic and mineral groups.
Organic compounds contain carbon and hydrogen. Some organic particles are found in the atmosphere more than other organic particles,
These include phenols, organic acids, and alcohols.
The most famous minerals in the atmosphere are nitrates, sulfates, and metals such as iron, lead, zinc, and vanadium.

Sources of pollutants

The air has natural pollutants such as fungal spores, plant seeds, particles of salt and smoke, and particles of dust from forest floods and eruptions of volcanoes.
Also, the air contains carbon monoxide gas produced naturally (CO) from the decomposition of methane (CH4) and hydrocarbons in the form of tropanes from pine trees, hydrogen sulfide (H2S) and methane (CH4) from the anaerobic degradation of organic matter.

The sources of pollutants, in general, can be classified into four main categories:

Includes motor vehicles, air vehicles, trains, ships and any kind of use or evaporation of gasoline,
Including the supply of energy and heat for residential, commercial and industrial purposes, power generating plants that operate with steam,
Such as the chemical industry, metallurgy, paper production, and oil refineries,
Includes residues from domestic and commercial use, coal waste and ash remaining from the burning of agricultural remains.


Organic compounds that only contain hydrogen and carbon are called hydrocarbons, which are generally divided into two groups.
• Aliphatic hydrocarbons
The aliphatic hydrocarbon group includes alkanes, alkenes, and alkanes.
The alkanes are saturated hydrocarbons that are not involved in atmospheric photochemical reactions.
The alkenes commonly referred to as olefins,
Are not saturated and somewhat active in photochemical in the atmosphere.
This group reacts at high concentrations in the presence of sunlight with nitrogen oxides
And secondary pollutants such as proxy acetyl nitrate (PAN) and ozone (O3).
The aliphatic hydrocarbons produced up to about 326 mg / m3 for human and animal health are not risky.

aromatic hydrocarbons

Aromatic hydrocarbons biochemically and biologically active, some of them potentially carcinogenic,
Either derived from benzene or related to it.
An increase in the incidence of lung cancer in urban areas has been attributed to multi-nuclear hydrocarbons exhausted from cars.
Benzo pyrin is the worst cancer of hydrocarbons.

Sources of hydrocarbons

Drive shaft and carburetors have the highest percentage of hydrocarbon release.
Complementary combustion equipment that works with the catalyst releases hydrocarbons and burns carbon monoxide and generates CO2 and water.
Hydrocarbon control technology derived from residential resources
Hydrocarbon control technology derived from residential sources include gravel, adsorption, condensation, and alternative materials.
The graveling process is carried out with supplementary combustion devices and catalytic burners.

Carbon monoxide

The carbon monoxide gas is odorless and colorless, tasteless and under normal conditions, it is chemically ineffective and has an average lifespan of about 2.5 months in the atmosphere.
At present, the amount of carbon monoxide in the atmosphere is ineffective or less effective on human assets, plants, and objects.
In high concentrations of carbon monoxide, due to its high tendency to absorb hemoglobin, it can seriously disrupt human respiratory metabolism.
The concentration of carbon monoxide in densely populated urban areas where heavy traffic and vehicle movement are slow,
Significantly increases.
Carbon sources are natural and human carbon monoxide.

Carbon monoxide control standards

When the amount of carbon monoxide in a short time reaches deadly levels and becomes an emergency,
To cope with such conditions, when the amount of CO reaches an average of 46 mg / m3 (40ppm) over a period of 8 hours,
Extreme control operations are performed which include:
Stopping industrial factories and blocking roads where there is usually a heavy traffic.
Absorption, adsorption, condensation, and combustion are the technical methods for controlling CO.

Sulfur oxides

These oxides include six different gas combinations:
Sulfur monoxide (SO), sulfur dioxide (SO2), sulfur trioxide (SO) sulfur tetraoxide (SO4), sulfur dioxide
Sulfur oxide (SO2) and sulfur heptoxides (S2O7). In the study of air pollution,
Sulfur dioxide and sulfur trioxide are most important.
Due to the relative stability of SO2 in the atmosphere, this can act as an oxidizing or reducing agent.
SO2, which reacts with other components present in the atmosphere in the form of a photochemical or catalytic process,
It can produce sulfuric acid droplets (H2SO4) and sulfuric acid salts.
SO2 reacts with water, producing sulfuric acid.
This weak acid is associated with more than 80% SO2 released into the atmosphere from human activities to burn solid and fossil fuels.

Sulfur oxide control standards

Extensive methods for controlling sulfur oxide include:
The use of fewer sulfur fuels, the separation of sulfur from fuel, the replacement of other energy sources,
Conversion of coal into liquid or gas, cleaning of combustion products.

Nitrogen oxides

It contains nitrogen monoxide (NO), nitrogen dioxide (NO2), nitrous oxide (N2O).
nitrogen cis-oxide (N2O3), are Nitrogen tetroxide (N2O4) and Nitrogen Pentoxide (N2O5).
Two important gases in the air pollution equations are:
Nitric acid (NO) and nitrogen dioxide, nitrogen dioxide, which is heavier than air and soluble in water.
In water, it forms nitric acid or nitric acid or nitric oxide (NO).
Nitric acid and nitro acid have fallen to the surface as a result of rainfall,
Or with ammonia in the atmosphere (NH3), which combines ammonium nitrate (NH4NO3).
In this case, NO2 is a component of plant nutrition.
NO2, which is a good absorbent energy in the ultraviolet radiation range,
In the production of secondary pollutants such as ozone, O3 plays an important role. The amount of NO released in the atmosphere is far more than NO2 released.
NO is produced in high-temperature combustion processes due to the combination of nitrogen and oxygen.

Nitrogen oxide sources

Some nitrogen oxides are naturally occurring and some form humans.
A small amount of NO2 comes from forest fires. Bacterial decomposition of organic matter also liberates NO2 in the atmosphere.
In fact, NO2-producing resources are approximately ten times as tight as human resources in urban areas of concentration and concentration.
The major part of NO2 generated from human resources is the combustion of fuel in residential and transport vehicles.

Nitrogen oxide control standards

Often control measurements for NO2 are released in order to limit combustion conditions and reduce NO2 production as well as the use of diverse equipment to remove NO2 from exhaust gases.

Photochemical oxidants

Oxidizers or full oxidizers are two phrases used to describe photochemical oxidizing agents and
Usually, they indicate the ability to oxidize the air in the atmosphere.
Ozone (O3), a major photochemical oxidizer, accounts for about 90% of oxidizing agents.
Other important photochemical oxidants in air pollution control are:
Neonatal oxygen (O), Excited molecular oxygen (O2), Proxy acyl nitrate (PAN), Proxy propanol nitrate (PPN)
Proxy butyl nitrate (PBN), nitrous oxide (NO2), hydrogen peroxide (H2O2) and alkyl nitrate.
The effects of oxidizing agents
The effects of oxidants on human health can cause coughing, shortness of breath, airway obstruction, chest pain,
Inappropriate lung function, red blood cell changes, dry swelling, and burning eyes, nose and throat.

Acid Properties
Acid Properties

Acid Properties

Acid Properties: A sharp water or acid (in Latin acids means sour) is a chemical substance.

The characteristics of its aqueous solutions include sour taste, the ability to change the color of the blue to red,

And also the ability to react with bases and some special metals (such as calcium) and salt formation.

 aqueous solutions have a pH less than 7.

The bottom pH means more acidity and a higher concentration of hydrogen ions.

Solutions or chemicals that have the same acidic properties are acidic.

Acid is said to be hydrogen-containing substances that can react with metals and produce hydrogen gas.

General Properties of Acids

  • The ingredients with the sour taste.
  • Their aqueous solution release proton ions.
  • Paint the litmus paper red.
  • Combined with some metals such as iron and zinc, and liberates hydrogen gas.
  • Reacts with alkalis (alkalis) and forms salts.
  • They react with calcium carbonate, for example, in the form of marble, so that they float and release carbon dioxide

Arrhenius’s theory of acids

When the chemical ionization concepts were clarified in aqueous solutions,

The concept of acid has changed considerably.

According to Arrhenius, acid is a is material that ionized in water, and it produces ion + H3O, which is sometimes shown as + H.

(HCl -> H + + Cl- (aq

Arnius also interpreted acidic power on this basis, saying that strong acid is almost completely ionized in aqueous solutions.

If the amount of acid dissolution is lower.

Notice that the Arrhenius concept is based on water ions.

By the definition of Arrhenius, the role of acid oxides can also be interpreted

Acid oxides

Many oxides of non-metals react with water and produce acid,

As a result, these substances are called acid oxides or acidic acid.

N2O5 (s) + H2O → H + + NO3-aq

The Bronsted-Lowry acid-base theory

By definition, Bronsted – Lowry, the acid is a substance that gives a proton to alkali.

Acids may be molecules or ions.

By removing the proton, the acid is converted to the alkali (alkali acid 1), and by acquiring the proton, the initial opening, the open 2, becomes acid 2 (the conjugate acid 2).

Acid 2 + open 1 <- acid 1 + open 2

The strength of acids is based on their desire to lose or absorb proton.

The stronger the acid, the weaker the alkali conjugate it is.

In one reaction, the balance in the formation of acid is weaker. Perchloric acid, HClO4, is the strongest acid, and its alkali conjugate, ion perchlorate, -ClO4, is the weakest alkali, and H2, the weakest acid and its conjugate, ion-hydride, + H, is the strongest open.

Louis’s theory of acids

According to Louis, acid is a substance that can form a covalent bond by accepting an open electron pair.

In Louis’s theory, the concept of the electron pair and the formation of covalent bonding are emphasized.

Luis’s definition of things is much broader than what he has said. Chemical compounds that can play the role of acid Louis include:

  • Molecules or atoms that have incomplete octaves.

(BH3 + F- → BH4- (aq

Many simple cations can play the role of acid Louis.

Cu + 2 + 4NH3 → Cu (NH3) 4 + 2

  • Some metal atoms form acid in the formation of compounds such as carbonyls produced by the reaction of metal with carbon monoxide:

Ni + 4CO → Ni (CO) 4

  • Compounds whose central atoms have a tiny expansion of their thickness,

In the reactions that this expansion extends to, they have an acid role,

For example, in the opposite reaction, the thickness of the central atom (Sn) extends from 8 to 2 electrons.

SnCl4 + 2Cl → SnCl6-2aq

Some compounds have acidic properties due to the presence of one or more double bonds in the molecule.

For example, CO2

Acidic Power and Molecular Structure

In order to investigate the relationship between molecular structure and acidity,

The acids are divided into two types:

Covalent hydrides and oxyacid.


Some hybrid covalent binary compounds (such as HCl, H2) are acidic.

Two factors affect the acidity of the hydride element:

Elemental electronegativity and elemental atomic size

. The acidity of the hydrides of the elements of a period increases from left to right, in line with the electronegativity of the elements.

An electronegative element takes up more electrons from hydrogen and accelerates its release as a proton.

The acidity of the hydrides of the elements of a group increases by increasing the size of the central atom.

In the second alternation: NH3> H2O> HF in group VI is as follows:

H2Te> H2Se> H2S> H2O


In these compounds, acidic hydrogen is attached to an O atom, and the change in the size of this atom is negligible.

Therefore, the key factor in the acidic power of these oxides is the electronegativity of the atom Z: H-O-Z.

If Z is a non-metallic atom with high electronegativity, it contributes to the reduction of the electron density around the O atom (in spite of intense oxygen electronegativity).

This phenomenon causes the oxygen atom to accelerate its separation by making the electron density of the H-O bond of the H atom, and make the composition acidic.

Hypocaloric acid, HOCl, is an acid of this type.

The greater the electronegativity of Z, the H-O bond electrons are far more atomic H, and it is easier to remove the proton: HOCl> HOBr> HOI.

In oxygen oxides where more oxygen atoms are attached to Z, acidity increases with increasing n

The most important strong acids

The molecules of these acids are completely ionized in dilute aqueous solutions.

Conventional acids are: chloride, iodide, nitric, sulfuric, per chloric acid.

The most important weak acids

Ionization of these acids is not complete in water and never reaches 100%.

The conventional examples are acetic acid, carbonic acid, fluoride acid, nitric acid and, to some extent, phosphoric acid.

Some uses of acids

sulfuric acid

One of the most powerful mineral acids with the formula H2SO4 is a light and dark oil.

An industrial utility that is used extensively in oil refining and in fertilizer, paint, pigments, dyes, and explosives.

acetic acid

An organic acid is a colorless liquid with the formula CH3COOH, which is also the basis for vinegar.

The major part of the world’s most acid-free, alcohol-based reaction is used to produce esters that are used as the best solvents in paint and polish.

Also, in pharmaceutical factories, the practice of natural rubber and the supply of artificial leather and as a solvent for many organic compounds of acetic acid is used.

nitric acid

A strong mineral acid with the formula HNO3, which is used by the user in nitrate fertilizers and ammonium phosphate fertilizers, nitro blast, plastics, dyes, and varnishes.

Sulfonic acid

These acids, with the general formula HSO3R, where R can be methane or benzene, etc.,

Soluble in water, non-volatile and absorbent, and as emulsifying agents,

Lubricants and lubricants are used to prevent corrosion and rust.

Hydrochloric acid

One of the strongest mineral acids with the formula H Cl, which is a pale yellow or slightly yellowish, is very corrosive and non-flammable.

The acid is dissolved in water, alcohol, benzene and used in the acidification (activation) of oil wells, waste boilers sedimentation, food industry, cleaning of metals, and so on.

what is purity?

what is purity?

What is purity? A measure of the net content of a substance.
The materials used in the lab or industry have some impurity.
They usually have different impurities.
Use purity or purity to indicate the net content of the material
Which follows the following relationship:
Mass of gross mass / Mass of pure matter = Degree of purity
Mass of gross mass / 100 * Mass of pure matter = Percent purity
For example, when we talk about sodium chloride 90% it means
If we divide this piece of salt into 100 parts, it is 90 parts pure sodium chloride and 10 parts are impurities.


Chemical formula: Na-OH

Molecular Weight: 40 CAS: 1310-73-2

RTECS: WB490000

Synonyms: Sodium hydroxide, caustic soda

Features: It is an odorless, white crystalline, transparent, non-volatile and highly corrosive.

Moisture absorbs air easily.


OSHA: 2 mg / m3

NIOSH: 2 mg / m3 / 15 min C; Group I Pesticide

ACGIH: 2 mg / m3 C

Materials and solutions required:

Sodium carbonate, with the original standard purity

Solution Acetate hydrochloric acid, 0.1 normal;

The basic standard is Sodium carbonate.

Hydrochloric acid, 0.01 normal; 10 ml of the acetic acid solution of hydrochloric acid 0.1 normal

Place in a 100 ml bottle of distilled water.

Distilled water is deionized, free of CO2, boiled then cooled with nitrogen.

Compressed Nitrogen

sodium hydroxide 50% (w / v);
50 g of caustic soda dissolved in distilled water

And the volume of 100 ml.

make a caustic soda stokes, 0.1 normal;
add 8 ml of 50% caustic soda to 1 liter CO2-free distilled water.

the practical standard solution of caustic soda, 0.01 normal;
10 ml solution of caustic soda stoke

Exert a 0.1% normal boil with 100 ml CO2-free distilled water

The standard buffer solution with pH 4 and 710-

Required equipment:

Sampler: 37 mm PTFE membrane filter with 1-micron pore size
(Millipore, Fluorophore or similar types).

With a celluloid support pad, with cassette in the filter holder.

Individual sampling pump with a discharge rate of 4-1 L / min,
with flexible interface pipes

pH meter with pH electrode and recorder

Titration container; balloons of 150 to 200 ml;

With a cover that has a hole for the PH electrode as well as the input and output N2

Magnetic stirrer

Glass rod, 5 mm in diameter and 10 cm in length,

To keep the filter below the liquid level in the titration vessel

Pipettes 5 and 10 ml

Balloons of 100 ml and 1 liter

A 50 ml burette with a grade of 0.1 ml



Calibrate individual sampler pumps.

Also, attach a sampler to the pump during calibration.

Perform sampling in a flow rate between 4-1 L / min for air volume flow of 70 to 1000 liters.

Do not allow more than 2 mg of total dust to be collected on the filter.


Transfer the sample filter to the titration container by tweezers.

Note that the surface on the filter is downward.

Due to the fact that during the analysis of the filter below the liquid level,

Place the glass rod end on the filter center to hold it.

Cover the titration container.

Add 5ml hydrochloric acid 0.01 in a titration vessel.

The titration vessel was placed in a magnetic stirrer and purified by N2 (0.1 L / min)


Let the titration container stay in the mixer for 15 minutes.

Calibration and quality control

Calibrate the pH gauge using buffer solutions (with pH equal to 4 and 7).

Adjust the amounts of 0.1% hydrochloric acid solution to sodium carbonate.

3 to 5 grams of standard sodium carbonate for 4 hours at 250 ˚C.

Then cool it in the desiccator.

Dissolve 2.5 g of sodium carbonate in 1 liter of CO2-free distilled water

And to obtain a sodium carbonate of 0.05 normal.

Transfer 5 ml of sodium carbonate solution 0.05 to the titration container

Start titration and continue until you reach PH 5.

Remove the PH electrodes and rinse it into the titration container.

To remove the dissolved CO2, add N2 to the contents of the titration container for 3 to 5 minutes.

Continue titration to the turning point.

Calculate the acidity of the hydrochloric acid solution by the following equation:

N_HCl = ((weighing g Na_2 CO_3) (titration in the case of use NaCl CO 2) / ((52.99)) used HCl ()

The practical Standard solution of caustic soda with the normal solution with the homogeneous hydrochloric acid solution.

Perform this according to step 2 of calibration, except that the hydrochloric acid solution is homogeneous

Alternate with sodium carbonate solution (Na2CO3) and a 0.1% normalized caustic soda solution with the normal hydrochloric acid solution.

Calculate the normality of the caustic soda titration using the following equation.

N1aOH = ((N-HCl) (mL HCl used)) / (mL NaOH used)

Prepare at least three spike checks in order to check the amount of recycling in the range for which the sample is intended.


The excess hydrochloric acid in the main sample, control and spike samples

Reverse titration with standardized (coherent) caustic soda.

Simultaneously clean up with nitrogen.

Look at the PH meter as you type.

Determine the end point (ml of caustic soda used normal 0.01)


Carbon dioxide in the air may

Reacts on the filter with alkali and forms carbonates

But it does not interfere with the titration.

Carbonates can cause positive interference.

Acid particles can neutralize the sample and have negative interactions


Calculate the concentration of caustic soda in the air using the following equation:

C = ((V_ (NaOH-b) -V_ (NaOH-S)) .N × 40 × 〖10〗 ^ 3) / V

In this regard:

C = concentration of caustic soda in mg / m3

The NaOH-b = volume of caustic soda in the titration of the control sample in milliliters

The NaOH-s = volume of caustic soda in the titration of the original sample in milliliters

N = Sodium nitride solution normalization

40 = Molecular weight of caustic soda

V = Sample volume of air in liters

The Caustic soda of Arax production group with a purity of 98.5% is ready to supply domestic and foreign markets.

Stay in touch with us.

Industrial production of caustic soda
Industrial production of caustic soda

 Industrial production of caustic soda

 Industrial production of caustic soda

 Sodium Hydroxide is a solid and white substance with a melting point of 1388 ° C and

a density of 13.2.

This material usually reaches 98% or 99% purity for various uses Sodium hydroxide is

presented in four ways in terms of its appearance:

Caustic soda liquid

Sodium hydroxide liquid is Produced by Using the Hydrolysis Process of a Salt Solution,

in Petrochemicals and Liquid caustic soda production Units then will be transported by

special thanks to caustic soda flakes production units.

Caustic soda flakes

Caustic soda flakes are usually in white color and odorless material and are available at the flake.

Caustic soda pearls:

Caustic soda pearls are solid, white and similar to small snowball bullets,

which are used in more precision and finer production?

It is commonly used in pharmaceutical and textile industries with more sensitive applications

Sodium Hydroxide Powder:

This caustic soda or sodium hydroxide, have fairly small grains.

The process of sodium hydroxide production

More than 95% of the chlorine production capacity and approximately 100% of sodium hydroxide

production capacity is based on the hydrolysis of brine Dissolution.

In this process, the sodium chloride solution is decomposed electro less to chlorine

(gas chlorine) and sodium hydroxide and hydrogen.

If instead of using salt water (sodium chloride),

a calcium chloride solution or potassium chloride as the raw material is used,

The reaction product will contain potassium or calcium instead of sodium.

There are also processes where hydrogen converts liquid chloride into hydrogen

and chlorine,

or sodium melted chloride to chlorine and metallic sodium.

In producing liquid sodium hydroxide, using sodium chloride as the raw material,

about 1126 kg of sodium hydroxide and 28 kg of hydrogen are produced per 1000 kg of chlorine.

A large amount of hydrogen produced in this process is used to produce ammonia,

hydrochloric acid, and hydrogenation of organic compounds.

  Sodium hydroxide production method

Three methods for producing caustic soda:




Producing liquid sodium hydroxide with diaphragm method:

Using the diaphragm method, chlorine, sodium hydroxide (Noah),

and hydrogen is produced simultaneously.

In this process, the two reactor sections are separated by a

permeable diaphragm plate, often made of asbestos.

In the diaphragm reactor, saturated brine enters the anode portion of the cell,

where the chlorine gas is released, and then It flows to the Cathode section.

The role of the diaphragm in this method is to isolate the salt solution from

the liquid sodium hydroxide in the cathode,

where the hydrogen gas is released there.

The product of the process is a dilute solution of Brine and liquid sodium hydroxide.

In this solution, the liquid Density should reach 50% and the salt should be removed.

Sodium hydroxide is spilled over into nickel trays for Condensation.

And is heated at 1400 ° C to condensation from 50% to 98%.

So, about 3 tons of water evaporates per ton of liquid sodium hydroxide

 Produce liquid sodium hydroxide with membrane method:

The most common method of sodium hydroxide production is hydrolysis of salt water

in a membrane cell.The difference in this method with the diaphragm method is that

around each of the electrodes in the solution,

surrounded by a diaphragm surrounded by a membrane.

The saturated salt water enters the first reactor chamber
(where chlorine gas is released)It turns out.

Chloride ions are oxidized by the anode and converted to chlorine gas

by losing electrons. In the cathode, the positive ions of hydrogen,

which are obtained by the decomposition of water molecules,

The electric current is restored to the hydrogen gas and the hydroxide

ions released into the solution are released.The ion penetrating membrane in

the middle of the cell only allows for positive ions of sodium to cross into the second part of the cell

While chloride ions remain in the anode section.

In the cathode, hydroxide ions react with sodium ions to produce sodium hydroxide.

The Obtained sodium hydroxide has a significantly lower sodium chloride (salt)

As a result, it has a higher purity and higher quality than diaphragm production

And there is no need for a desalination process.

Produce liquid sodium hydroxide with mercury method:

In this method known as the Kestner-Kellner Process, the salt water saturation

the solution is placed above a thin layer of mercury.

In this process, mercury plays a role as a cathode and interacts with the sodium

formed in the solution, and a mixture of sodium and mercury (amalgam) is obtained.

Sodium-mercury amalgam is continuously released from the reactor and reacted with water,

which leads to the decomposition of this mixture with sodium hydroxide, hydrogen, and mercury.

The mercury is recovered from the mercury process and the chlorine formed in the anode is released

into the gas from the reactor.

Production of caustic soda flakes

Caustic soda is produced by utilizing the liquid caustic soda of petrochemicals during the process

of thickening and evaporation.

The process of producing caustic soda flakes is such that at first sodium hydroxide 50% liquid

is transmitted by special tanks to caustic soda flakes manufacturing companies.

And then, the liquid caustic soda during the process of production in the condensing lines,

while evaporating the water in it, turns into a solid caustic soda of 98-99%.