Thiourea dioxide This is john mao from henan hongye chemical co., ltd, which is the biggest manufacturer and supplier of thiourea dioxide(bleaching agent) in the world. We can produce 16, 000mt thiourea dioxide per year. The only one manufacturer in china has iso 9001:2000 & iso 14001. Specification: product properties Standard specifications Purity, % Min. 99 Thiourea, % Max.0.1 Moisture, % Max. 0.05 Iron, ppm Max. 10 Sulphate, % Max. 0.17 Appearance White crystal power Odor Odorless Packing 25 kg plastic bags, or 50 kg fiber drums According to customers'demands