Phenolsulfonic acid

Phenolsulfonic acid (CAS 1333-39-7), also known as benzenesulfonic acid monohydrate, is a strong organic acid used industrially as a catalyst and pH-regulating agent.

Its combination of acidic and phenolic functionality makes it effective in driving reactions and controlling process chemistry across multiple manufacturing sectors and industrial applications.

In pharmaceutical manufacturing, it functions as an acid catalyst in synthesis steps and as a counterion in salt formation for active pharmaceutical ingredients during complex chemical production.

Textile processors use it in dyeing and finishing baths to regulate pH and improve dye uptake consistency across fiber types, ensuring high-quality results in large-scale textile manufacturing.

In leather processing, it supports tanning and retanning operations where controlled acidity is critical to hide penetration and finish quality for various commercial leather goods.

Water treatment applications include use as a sulfonating agent and process chemical where precise pH control is required in industrial effluent systems and environmental management protocols.

Phenolsulfonic acid is supplied as an aqueous solution, with concentration typically ranging around 65% w/w, though other concentrations are available to meet specific process requirements.

Technical grade is the standard commercial offering for industrial applications. Pharmaceutical-grade material is available for API synthesis and regulated manufacturing environments.