Thiourea

Appearance and Properties: White, lustrant, bitter-tasting crystals.

Melting Point (℃): 176～178

Boiling Point (℃): Decomposes; Relative Density (water=1): 1.41

Logarithmic value of Octanol/Water partition coefficient: 2.5

Solubility: Soluble in cold water and ethanol; slightly soluble in ether.

Main Uses

Pharmaceutical and Pesticide Industries

As a drug intermediate: Used in the synthesis of sulfa drugs (e.g., sulfathiazole), antithyroid drugs (e.g., methimazole), and antitumor drugs. The sulfur atom of thiourea participates in the structural construction of biologically active molecules.

Production of pesticides: Used in the synthesis of insecticides (e.g., thiourea insecticides), fungicides (e.g., isoprothiolane), and herbicides, utilizing their inhibitory effects on pests or pathogens.

Metallurgy and Electroplating Industries

Metal beneficiation: Acts as a flotation agent for sulfide ores. It can selectively adsorb onto the surface of metal sulfide ores, enhancing the adhesion between minerals and bubbles, thereby improving beneficiation efficiency (e.g., separation of copper, lead, and zinc ores).

Electroplating additive: Used in electroplating solutions to improve the gloss and uniformity of the coating and prevent pinholes or cracks. Commonly used in the electroplating of metals such as copper and silver.

Metal corrosion inhibitor: Added to industrial water or lubricating oil. It forms a protective film by binding to the metal surface, slowing down metal corrosion (e.g., corrosion prevention for steel and copper).

Organic Synthesis

As a reducing agent: Reduces nitro, nitroso, and other groups in organic reactions, or is used to prepare thiols, isothiocyanates, and other compounds.

Used to synthesize heterocyclic compounds: Reacts with aldehydes and ketones to form heterocycles such as thiazoles and imidazoles. These structures are core skeletons for many drugs and dyes.

Chemical and Materials

Production of thiourea resin: Condenses with formaldehyde to produce thermosetting resins used in adhesives, coatings, or molding plastics, possessing acid and alkali resistance resistance.

As a rubber vulcanization accelerator: Accelerates the rubber vulcanization reaction and improves the hardness and wear resistance of rubber (e.g., in the processing of natural and synthetic rubber).

Used in the paper industry: Acts as a bleaching aid to enhance pulp brightness, or as a water repellent for paper.

CAS NO: 62-56-6

EC NO: 200-543-5

Molecular Formula: CH₄N₂O₄S

Molecular Weight: 140.1185

Alias: ;Thiourea;Sulfourea;

Structural Formula: