What are the various uses of sulfuric acid 98 percent?

Sulfuric acid at 98% concentration refers to highly concentrated H₂SO₄, a dense, oily liquid commonly used in industry. At this purity, it is close to the maximum concentration that can be maintained without significant fuming. It is a strong mineral acid known for its ability to dehydrate, oxidize, and corrode many materials. Because of its strength, it must be handled with great care.

What Exactly Is 98% Sulfuric Acid? 

Pure sulfuric acid is H₂SO₄, and the 98% grade is the most commercially available concentrated form. It is not called “sulfuric hydroxide”—that term is incorrect. In water, sulfuric acid dissociates strongly to produce hydronium ions (H₃O⁺), making it one of the most powerful acids in routine chemical use.

Major Uses of Concentrated Sulfuric Acid 

1. Fertilizer Production

Sulfuric acid plays a key role in producing phosphate fertilizers. It reacts with phosphate rock to form superphosphate or phosphoric acid, which is then used to manufacture fertilizers such as ammonium phosphate.

2. Detergents and Cleaning Products 

It is widely used in the chemical industry to make surfactants for detergents. In controlled concentrations, sulfuric acid also appears in heavy-duty cleaners for removing mineral deposits, rust stains, or organic residue from stone, metal surfaces, and industrial equipment.

3. Bleaching and Textile Processing

Concentrated H₂SO₄ is used in producing agents that help lighten or remove color in textiles. It also helps prepare fibers for dyeing and finishing. 

4. Water Treatment

In water treatment facilities, sulfuric acid helps adjust alkalinity and remove excess minerals such as calcium carbonate. This helps prevent scaling in pipes and improves water quality.

5. Steel Pickling

Before steel is coated or painted, it is often “pickled” in dilute sulfuric acid to remove rust, scale, and impurities. This creates a clean surface ready for further processing or coating.

6. Metal Processing and Electroplating

Sulfuric acid is used in electrolytes for electroplating and metal finishing. In appropriate concentrations, it supports deposition of metal layers on objects to improve strength, appearance, or corrosion resistance.

7. Rubber and Plastic Manufacturing

Sulfuric acid is involved in producing raw materials for PVC (polyvinyl chloride) and other polymers. It is also used in processing natural rubber and petroleum-based elastomers.

8. Petroleum Refining 

Refineries use sulfuric acid as a catalyst in alkylation, a process that improves gasoline quality by producing high-octane fuel components.

9. Wood Treatment

In wood-processing chemicals, sulfuric acid assists in cleaning and preparing wood, helping prevent fungal growth and improving the penetration of preservatives.

10. Leather Industry

Leather tanneries use sulfuric acid in controlled amounts to remove stains, adjust pH during processing, and prepare hides for tanning.

Safety Notes

Because 98% H₂SO₄ is highly corrosive and reacts vigorously with water, it can cause severe burns and must be handled with proper protective equipment. It should always be added slowly to water, never the reverse, to prevent violent splattering.