Description

p-Toluenesulfonic Acid Monohydrate is a versatile and widely used organic acid catalyst and reagent. This compound is valued for its strong acidity, solubility in various organic solvents, and utility as a dehydrating agent in synthetic chemistry. It is essential for manufacturers and R&D laboratories in the pharmaceutical, agrochemical, polymer, and specialty chemical industries seeking efficient acid-catalyzed reactions.

Application

• Pharmaceutical Synthesis: A key catalyst and reagent in the production of active pharmaceutical ingredients (APIs), particularly for esterification, acetal formation, and dehydration reactions.
• Polymer & Resin Production: Used as a curing agent and catalyst in the manufacture of phenolic resins, epoxy resins, and other thermosetting polymers.
• Agrochemical Formulation: Employed as an intermediate and catalyst in the synthesis of pesticides, herbicides, and plant growth regulators.
• Organic Synthesis & Fine Chemicals: Serves as a powerful acid catalyst for a wide range of organic transformations, including Friedel-Crafts alkylation, protection/deprotection of functional groups, and cyclization reactions.
• Dye & Pigment Manufacturing: Acts as a sulfonating agent and catalyst in the production of various dyes and organic pigments.
• Electroplating & Surface Treatment: Utilized in specific electroplating baths and as an additive in metal surface treatment processes.

Basic Information

Product Name	p-Toluenesulfonic Acid Monohydrate
CAS No.	104-150-4
Molecular Formula	C7H8O3S · H2O
Molecular Weight	190.22 g/mol
Synonyms	4-Methylbenzenesulfonic Acid Monohydrate; Tosic Acid Monohydrate; PTSA Monohydrate; Toluenesulfonic Acid Monohydrate; p-TSA Monohydrate; 4-Toluenesulfonic Acid Hydrate; Toluenesulfonic Acid Hydrate; p-Toluenesulfonic Acid Hydrate
EINECS	203-180-0

Quality Control

Our p-Toluenesulfonic Acid Monohydrate is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, identity, and performance. A comprehensive Certificate of Analysis (COA) detailing assay, impurity profile, and physical properties is provided with every shipment to guarantee traceability and compliance with your quality requirements.

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). This product is hygroscopic (moisture-sensitive); containers must be kept tightly sealed to prevent absorption of atmospheric moisture, which can affect product quality and handling properties.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms
Assay (Titration)	≥ 98.0 %
Water Content (KF)	8.5 - 9.5 %
Melting Point	103 - 107 °C
Residue on Ignition	≤ 0.1 %
Heavy Metals (as Pb)	≤ 20 ppm

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