ITEM Specification Specification Main Content (on NH4CL basis) 99.3% 99.5% Moisture 0.5% 0.7% Total sulphur (on SO4 basis) --- 0.02% Iron(on Fe basis) 0.001% 0.001% Ignition loss at (500-600?) 0.2% 0.4% Heavy matal(Pb) 0.001% 0.005% PH Value(200g/l) 4.0-5.8 4.0-5.8 White crystal