Description

4-Hydroxybenzenesulfonic Acid is a versatile aromatic sulfonic acid derivative, serving as a crucial intermediate in fine chemical synthesis. Its bifunctional structure, featuring both a phenolic hydroxyl and a sulfonic acid group, makes it a valuable building block for creating more complex molecules. This compound is essential for manufacturers in the pharmaceutical, agrochemical, and specialty chemical industries seeking to develop dyes, UV absorbers, and other performance chemicals.

Application

• Pharmaceutical Intermediate: Key starting material for the synthesis of various active pharmaceutical ingredients (APIs) and diagnostic agents.
• Dye and Pigment Manufacturing: Acts as a coupling component and intermediate in the production of azo dyes and other colorants.
• UV Stabilizer Production: Used in the synthesis of benzophenone and benzotriazole-type UV absorbers for plastics and coatings.
• Agrochemical Synthesis: Intermediate in the manufacture of certain herbicides, fungicides, and plant growth regulators.
• Electroplating Additive: Functions as a brightening agent and leveler in specific electroplating bath formulations.
• Chemical Research & Development: Employed as a reagent in organic synthesis and catalysis research.
• Surfactant and Detergent Intermediate: Used to produce specialized anionic surfactants.

Basic Information

Product Name	4-Hydroxybenzenesulfonic Acid
CAS No.	98-67-9
Molecular Formula	C6H6O4S
Molecular Weight	174.17 g/mol
Synonyms	Phenol-4-sulfonic Acid; p-Phenolsulfonic Acid; 4-Hydroxybenzenesulfonate; Benzenesulfonic acid, 4-hydroxy-; p-Hydroxybenzenesulfonic Acid; 4-Sulfophenol; Phenolsulfonic Acid (isomer)
EINECS	202-691-1

Quality Control

Our 4-Hydroxybenzenesulfonic Acid is produced under a stringent quality management system. Each batch is tested to ensure it meets precise specifications for purity, identity, and impurity profiles. We provide comprehensive Certificates of Analysis (COA) with every shipment, detailing results from analytical methods such as HPLC, titration, and spectroscopy. Our quality commitment supports compliance with REACH and other relevant global regulatory frameworks.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Due to its hygroscopic nature, the container must be kept tightly sealed to prevent moisture absorption. Keep away from strong oxidizing agents, strong bases, and incompatible materials.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Loss on Drying	≤ 2.0%
Sulfated Ash	≤ 0.1%
Heavy Metals (as Pb)	≤ 20 ppm
Related Substances (HPLC)	Total impurities ≤ 2.0%

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.