Hydrochloric acid

Raw materials

1. Hydrogen chloride

2. Water

Process

Hydrochloric acid is prepared by dissolving hydrogen chloride in water.

Product

Hydrochloric acid

Used for

Pickling of steel, production of organic and inorganic compounds, pH control, neutralization, regeneration of ion exchangers, leather processing, purification of common salt, household cleaning

Production facility

Victor Harbor, SA

Export

Bandar Seri Begawan, Brunei

Ammonia

Raw materials

1.Nitrogen

2. Hydrogen

Process

Harber Process

Nitrogen from the air is combined with hydrogen derived mainly from natural gas (methane) with the presence of iron catalyst to produce ammonia. The reaction is reversible and the production of ammonia is exothermic.

N₂ (g) + 3 H₂ (g) ⇌ 2 NH₃ (g)   (ΔH = −92.22 kJ·mol⁻¹)

Product

Ammonia

Used in

Fertilizer, precursor to nitrogenous compounds (virtually all synthetic nitrogen compounds are derived from ammonia), cleaners (clean glass, porcelain and stainless steel; cleaning ovens; soaking items to loosen baked-on grime), fermentation (as a source of nitrogen for microorganisms and to adjust pH during fermentation), plastics, fibers, explosives, intermediates for dyes and pharmaceuticals.

Production facility

Burrup Peninsula, WA

Export

Brasilia, Brazil

Nitric acid

Raw materials

1. Ammonia

2. Oxygen

Process

Ostwald Process

Ammonia is converted to nitric acid in two stages.

1. Ammonia is oxidized by heating with oxygen in the presence of a catalyst such as platinum with 10% rhodium to form nitric oxide and water with typical conditions of (which contribute to an overall yield of about 96%) pressure between 4-10 atm and temperature of 900 °C. This step is strongly exothermic, making it a useful heat source once initiated:

4 NH₃ (g) + 5 O₂ (g) → 4 NO (g) + 6 H₂O (g) (ΔH = −905.2 kJ)

2. Stage two (combining two reaction steps) is carried out in the presence of water in an absorption apparatus. Initially nitric oxide is oxidized again to yield nitrogen dioxide:

2 NO (g) + O₂ (g) → 2 NO₂ (g) (ΔH = −114 kJ/mol)

This gas is then readily absorbed by the water, yielding the desired product (nitric acid, albeit in a dilute form), while reducing a portion of it back to nitric oxide:

3 NO₂ (g) + H₂O (l) → 2 HNO₃ (aq) + NO (g) (ΔH = −117 kJ/mol)

The NO is recycled, and the acid is concentrated to the required strength by distillation.

Product

Nitric acid

Used for

Rocket fuel, chemical reagent, woodworking (artificially age pine and maple)

Production facility

Port Lincoln, SA

Export

Gaborone, Botswana

Nitrogen dioxide

Raw material

1. Nitric acid

Process

Nitrogen dioxide, NO₂ is prepared in a two step procedure by thermal decomposition of dinitrogen pentoxide, which is obtained by dehydration of nitric acid:

2 HNO₃ → N₂O₅ + H₂O

2 N₂O₅ → 4 NO₂ + O₂

Product

Nitrogen dioxide

Used as

Catalyst in certain oxidation reactions, inhibitor to prevent polymerization of acrylates during distillation, nitrating agent for organic compounds, oxidizing agent, rocket fuel, flour bleaching agent, increasing the wet strength of paper

Production facility

Port Pirie, SA

Export

Sarajevo, Bosnia and Herzegovina

Sulfuric acid

Raw materials

1. Sulfur

2. Oxygen

3. Water

Process

a. Contact Process (DCDA)

1. Sulfur burned to produce sulfur dioxide.

S (s) + O₂ (g) → SO₂ (g)

2. The sulfur dioxide is oxidized to sulfur trioxide using oxygen in the presence of vanadium(V)oxide catalyst.

2 SO₂ (g) + O₂ (g) → 2 SO₃ (g) (in presence of V₂O₅)

3. Sulfur trioxide is absorbed into 97–98% H₂SO₄ to form oleum (H₂S₂O₇), also known as fuming sulfuric acid. The oleum is then diluted with water to form concentrated sulfuric acid.

H₂SO₄ (l) + SO₃ → H₂S₂O₇ (l)

H₂S₂O₇ (l) + H₂O (l) → 2 H₂SO₄ (l)

(Note that directly dissolving SO₃ in water, SO₃ (g) + H₂O (l) → H₂SO₄ (l), is not practical due to the highly exothermic nature of the reaction between sulfur trioxide and water. The reaction forms a corrosive aerosol that is very difficult to separate, instead of a liquid.)

b. Wet sulfuric acid process (WSA)

1. Sulfur burned to produce sulfur dioxide.

S(s) + O₂(g) → SO₂(g)

or, alternatively, hydrogen sulfide (H₂S) gas is incinerated to SO₂ gas.

2 H₂S + 3 O₂ → 2 H₂O + 2 SO₂ (−518 kJ/mol)

2. The sulfur dioxide is oxidized to sulfur trioxide using oxygen with vanadium(V)oxide catalyst.

2 SO₂ + O₂ → 2 SO₃ (−99 kJ/mol) (reaction is reversible)

3. The sulfur trioxide is hydrated into sulfuric acid H₂SO₄.

SO₃ + H₂O → H₂SO₄(g) (−101 kJ/mol)

4. The sulfuric acid is condensed to liquid 97–98% H₂SO₄.

H₂SO₄(g) → H₂SO₄(l) (−69 kJ/mol)

Product

Sulfuric acid

Used in

Lead-acid batteries (for cars and other vehicles), ore processing, fertilizer manufacturing, oil refining, wastewater processing, chemical synthesis

Production facility

Port Augusta, SA

Export

Sucre, Bolivia

Sulfur dioxide

Raw material

a. Sulfur

b. Hydrogen sulfide and organosulfur 

c. Sulfide ores such as pyrite, sphalerite, and cinnabar (mercury sulfide)

Process

a. Sulfur dioxide is the product of the burning of sulfur:

S₈ + 8 O₂ → 8 SO₂

b. The combustion of hydrogen sulfide and organosulfur compounds proceeds similarly.

2 H₂S + 3 O₂ → 2 H₂O + 2 SO₂

c. The roasting of sulfide ores such as pyrite, sphalerite, and cinnabar (mercury sulfide) also releases SO₂:

4 FeS₂ + 11 O₂ → 2 Fe₂O₃ + 8 SO₂

2 ZnS + 3 O₂ → 2 ZnO + 2 SO₂

HgS + O₂ → Hg + SO₂

Product

Sulfur dioxide, SO₂

Used for

Precursor to sulfuric acid, preservative, winemaking, reducing agent, refrigerant

Production facility

Port Adelaide, SA

Export

Sucre, Bolivia

Sulfur trioxide

Raw material

1. Sulfur dioxide, SO₂

Process

Purified SO₂ is then oxidised by atmospheric oxygen at between 400 and 600 °C over a catalyst consisting of vanadium pentoxide (V₂O₅) activated with potassium oxide K₂O on kieselguhr or silica support. Platinum also works very well but is too expensive and is poisoned (rendered ineffective) much more easily by impurities.

Product

Sulfur trioxide, SO₃

Used for

In process plant environment, SO₃ gas is mixed into flue gas from combustion to make the ashes charged up before flowing through electrostatic precipitators. The electrostatic precipitators will then trap the ashes, making cleaner process emission possible.

Production facility

Murray Bridge, SA 

Export

Thimphu, Bhutan