What Is Sulfuric Acid? Properties, Grades and Industrial Uses

Sulfuric acid (H 2SO 4) is a thick, highly acidic liquid. The majority of the fertilizer industry uses sulfuric acid. Plants will typically purchase sulfuric acid, between 93-98% concentration, from a sulfuric acid manufacturer. This acid will be clear to pale yellow, viscous and heavy. Each batch can be traced back to the manufacturer.

The numbers on the datasheet

Each molecule can give up two protons, which is why a small dose shifts pH so hard. It also mixes with water completely, and that mixing throws off serious heat. Hence the old rule on every safety sheet: acid into water, never water into acid. Concentrated acid dehydrates organic material too, which is handy in synthesis and miserable on skin.

Any sulfuric acid manufacturer will quote values close to these:

Property	Value
Chemical formula	H₂SO₄
CAS number	7664-93-9
Molecular weight	98.08 g/mol
Density at 98% assay	1.84 g/cm³
Appearance	Clear, colorless to slightly yellow, viscous
Water solubility	Fully miscible, strongly exothermic
Typical shelf life	1–2 years, properly stored

Three grades, and why the certificate matters more than the label

Suppliers list industrial, fertilizer and battery grade, usually between 93% and 98%, with other concentrations on request. The names are useful shorthand. They aren't a specification. What you actually compare is assay and contaminant limits on the certificate of analysis, and battery use is generally the least forgiving of metal impurities.

My view: don't buy on price per tonne alone. A cheaper load that drifts a few points off assay costs you in dosing corrections, and nobody budgets for that. Ask any sulfuric acid manufacturer for a COA before the first order, not after the first complaint.

Where the acid actually goes

Ask a sulfuric acid manufacturer who buys the stuff and the list gets long.

Application	What the acid does	Typical user
Phosphate fertilizers and sulphate salts	Reacts with raw materials to form nutrient products	Fertilizer and agrochemical makers
pH control	Brings alkaline process or water streams down to target	Water treatment and process units
Petroleum refining	Acts as catalyst in alkylation	Refineries
Metal pickling	Strips scale and oxide from surfaces	Metal processing units
Lead-acid batteries	Serves as the electrolyte	Battery manufacturers
Chemical synthesis	Works as catalyst, dehydrating agent and reagent	Specialty chemical companies

In fertilizer plants the acid is used in phosphate fertilizers and sulphate salts. This means that the viscosity will affect the availability of nutrients in the finished product. The concentrated acid will mean less volume is needed to achieve the desired pH. Dilution will be required on site, therefore your tanks, pumps and pipework will need to be acid compatible.

Storage, drums and paperwork

Sulfuric Acid is hygroscopic. At all of our sites someone will ask if they are still 98% after sitting in an only half full drum for a month. The answer to this is, if the lid was sealed then yes. Sulfuric acid has a shelf life of 1-2 years depending on storage conditions. It should be stored in sealed containers made of corrosion resistant material.

Sulfuric acid is supplied in HDPE drums, IBC tanks and bulk tankers. If ordering internationally then the sulfuric acid exporter will need to supply you with a COA, MSDS, packing note and commercial invoice. They will also need to supply any documentation required by the destination country. Any missing information on a hazardous cargo document can cause a container to be held at port. A reliable sulfuric acid supplier will ensure this does not happen so it is worth asking who prepares the documentation and how quickly it can be turned around.

Sourcing from Vrik Pharma in Gujarat

Vrik Pharma is an ISO certified manufacturer of sulfuric acid. We have been in the chemical industry for 18 years. Our head office is located at Vapi and the manufacturing unit located at Sarigam GIDC. We are a sulfuric acid supplier and exporter. We supply industrial grade, fertilizer grade & battery grade sulfuric acid (93% - 98%) to domestic and international clients. We provide COA and MSDS along with our supply. Minimum order quantity is 500kg.

For a prompt response from a sulfuric acid manufacturer please fill out our bulk quote form on vrikpharma.com/sulfuric-acid providing us with your grade, concentration, quantity and destination. Alternatively please contact us on [email protected]. For export inquiries please call +91 93275 95918.