5-Sulfosalicylic Acid Dihydrate CAS 5965-83-3

Introduction to 5-Sulfosalicylic Acid Dihydrate

5-Sulfosalicylic Acid Dihydrate is a polyfunctional aromatic acid produced via sulfonation of salicylic acid, followed by recrystallization as the stable dihydrate form. It carries three reactive functional groups – phenolic hydroxyl, carboxylic acid and sulfonic acid – giving it strong acidity, water solubility and metal chelating capability. It appears as white crystalline powder at room temperature, freely soluble in water and ethanol, and slightly soluble in ether.

The dihydrate crystal form offers improved storage stability and flowability compared to the anhydrous grade, reducing caking and ensuring accurate dosing. It forms stable colored complexes with polyvalent metal ions such as iron, copper and titanium, making it valuable for both analytical detection and industrial sequestration processes.

5-Sulfosalicylic Acid Dihydrate Chemical & Physical Properties

Applications of 5-Sulfosalicylic Acid Dihydrate

Pharmaceutical intermediates: Used as a building block for synthesizing sulfa drugs, antipyretic analgesics and other active pharmaceutical ingredients. It also functions as an acidifying agent and metal chelator in drug formulation and purification processes.

Dye and pigment manufacturing: Serves as a coupling component for producing azo acid dyes and direct dyes. The sulfonic acid group enhances water solubility and dye affinity, improving color fastness and leveling performance on textile fibers.

Metal chelating and analytical reagent: Widely used in analytical chemistry for colorimetric determination of iron ions. In industry, it acts as a sequestering agent in electroplating, water treatment and surface finishing, masking heavy metal ions and preventing precipitation and discoloration.

Cosmetic and personal care: Incorporated into skin care formulations as a keratolytic agent and chelating stabilizer. It sequesters trace metal ions to prevent formulation oxidation, discoloration and rancidity, extending product shelf life.

Storage & Safety Precautions for 5-Sulfosalicylic Acid Dihydrate

• Store in tightly sealed containers in a cool, dry, well-ventilated warehouse. Protect from moisture and high humidity to prevent caking and content drift. Keep away from strong bases and oxidizing agents.
• Wear safety goggles, dust masks and nitrile gloves during bulk powder handling. Avoid inhalation of dust, which causes irritation to the respiratory tract and eyes. Rinse thoroughly with water after skin or eye contact.
• The material is acidic. Do not mix with alkaline materials in concentrated form, which may cause exothermic neutralization reactions. Store separately from food and feed materials.

5-Sulfosalicylic Acid Dihydrate FAQ

Q: What are the main industrial uses of 5-Sulfosalicylic Acid Dihydrate?

A: It is used as a pharmaceutical and dye intermediate, a metal chelating reagent in analysis and water treatment, and a stabilizing agent in cosmetic formulations.

Q: What is the advantage of the dihydrate form over anhydrous grade?

A: The dihydrate crystal form has better storage stability and flowability, is less prone to caking, and supports more accurate dosing in production processes.

Q: What storage precautions apply to 5-Sulfosalicylic Acid Dihydrate?

A: Store sealed in a cool, dry place away from moisture, strong bases and oxidizers. Wear dust protection and eye protection during bulk handling.