Description

Toluene Sulfonic Acid CAS NO 25231-46-3 is a versatile and highly effective organic acid catalyst and intermediate, primarily supplied as para-toluene sulfonic acid (p-TSA). This compound matters for its strong acidity in organic solvents, making it a superior alternative to mineral acids in numerous synthetic processes due to its solubility and ease of handling. It is essential for manufacturers in the pharmaceutical, agrochemical, polymer, and specialty chemical industries who require a reliable and efficient acid catalyst for esterification, condensation, and polymerization reactions.

Application

• Pharmaceutical Synthesis: A key catalyst and building block in the production of active pharmaceutical ingredients (APIs), particularly for esterification and protection/deprotection reactions.
• Polymer Industry: Widely used as a curing agent and catalyst in the production of phenolic, epoxy, and alkyd resins, as well as in polycarbonate manufacturing.
• Agrochemical Formulations: Serves as an intermediate and catalyst in the synthesis of herbicides, pesticides, and other crop protection agents.
• Dye and Pigment Manufacturing: Acts as a catalyst and sulfonating agent in the synthesis of various dyes, pigments, and optical brighteners.
• Electroplating & Metal Treatment: Used in electroplating baths and as a component in metal cleaning and surface treatment formulations.
• Organic Synthesis: A fundamental reagent for acid-catalyzed reactions including esterification, etherification, dehydration, and the Beckmann rearrangement.

Basic Information

Product Name	Toluene Sulfonic Acid
CAS No.	25231-46-3
Molecular Formula	C7H8O3S
Molecular Weight	172.20 g/mol
Synonyms	p-Toluenesulfonic Acid; 4-Methylbenzenesulfonic Acid; Tosic Acid; PTSA; Toluenesulfonic Acid; 4-Toluenesulfonic Acid; p-TSA; Toluene-4-sulfonic Acid
EINECS	246-773-1

Quality Control

Our Toluene Sulfonic Acid is manufactured under strict quality management systems. Every batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, acidity, and impurity profiles. We provide comprehensive Certificates of Analysis (COA) with each shipment, detailing key parameters such as assay, water content, and sulfate ash. Our production adheres to cGMP principles where applicable, ensuring consistent quality and supply reliability for critical B2B applications.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area away from incompatible materials such as strong bases, oxidizing agents, and moisture. Recommended storage temperature is between 15°C and 25°C. Due to its hygroscopic nature, containers must be kept tightly sealed after initial use to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystals or powder
Identification (IR)	Conforms
Assay (p-TSA)	≥ 98.5 %
Water Content (KF)	≤ 1.0 %
Sulfate Ash	≤ 0.1 %
Iron (Fe)	≤ 10 ppm
Heavy Metals (as Pb)	≤ 10 ppm

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