... sulphate is also extra pure.its nitrogen content is 21%.As with their various fuction,They usually used ... cost.4.Usage:1>Mainly use in fertilizer, its advantage is less absorb moisture compared ... to other fertilizer.2>use in industry ,pharmaceuticals,textiles,welding ... agent Storage battery making, making compound fertilizer 98% Ammonium Sulphate (NH4)2SO4 with Nitrogen 21%