Description

Silicotungstic Acid CAS NO 12363-31-4 is a versatile heteropoly acid catalyst and analytical reagent. It is valued for its strong acidity and stability, making it an effective and reusable catalyst in various organic synthesis and industrial processes. This compound is essential for manufacturers and research laboratories in the chemical, pharmaceutical, and petrochemical sectors seeking efficient catalytic solutions.

Application

• Catalysis: Acts as a highly efficient, reusable acid catalyst for esterification, alkylation, and condensation reactions in fine chemical synthesis.
• Analytical Chemistry: Used as a selective precipitating agent for the detection and quantification of alkaloids, proteins, and other basic compounds.
• Material Science: Serves as a precursor or additive in the fabrication of proton-conducting membranes for fuel cells and advanced functional coatings.
• Pharmaceutical Intermediates: Facilitates key synthetic steps in the production of active pharmaceutical ingredients (APIs) and drug intermediates.
• Textile & Dye Industry: Employed as a mordant in dyeing processes to improve color fastness and fabric treatment.
• Environmental Technology: Investigated for use in photocatalytic degradation processes for wastewater treatment.

Basic Information

Product Name	Silicotungstic Acid
CAS No.	12363-31-4
Molecular Formula	H4O40SiW12 (Common Hydrate: H4[SiW12O40]·xH2O)
Molecular Weight	2878.17 g/mol (Anhydrous)
Synonyms	Tungstosilicic Acid; Silicon Tungstate; Dodecatungstosilicic Acid; STA; H4SiW12O40; Keggin Acid; 12-Tungstosilicic Acid; Tungstic Acid, Silico-
EINECS	235-638-6

Quality Control

Our Silicotungstic Acid is manufactured under a strict quality management system. Each batch undergoes comprehensive analytical testing to ensure it meets high-purity standards for catalytic and reagent applications. A detailed Certificate of Analysis (COA) is provided with every shipment, confirming key parameters such as assay, heavy metal content, and loss on drying.

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 material is hygroscopic (moisture-sensitive) and should be handled in a dry environment to prevent caking or decomposition. Keep away from strong bases and incompatible materials.

Specification

Item	Specification
Appearance	White to pale yellow crystalline powder
Identification (IR)	Conforms
Assay (as H4SiW12O40)	≥ 98.0 %
Loss on Drying	≤ 5.0 %
Chloride (Cl)	≤ 0.01 %
Sulfate (SO4)	≤ 0.02 %
Heavy Metals (as Pb)	≤ 0.002 %
Iron (Fe)	≤ 0.005 %

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