Superfine Ammonium Phosphate Salt, Anti-caking Study

At present, the main trend of fire extinguishing agent - ammonium phosphate dry chemical is superfine to improve extinguishing efficiency. Ammonium phosphate superfine powder posessses large surface, and reacted with moisture easily to cake. The research purpose of this thesis is to modificate ammonium phosphate superfine powder to reduce hygroscopicity and caking capability .The wet process was adopted to modificate ammonium phosphate superfine powder with titanate NDZ-311, silicane KH550, zircoaluminate(Y) coupling agents, polyvinyl butyral(PVB), composites of octadcylamine and PVB, composites of zircoaluminate(Y) and PVB respectively. The study results show that the modification effect of coupling agents was better than PVB polyvinyl butyral; effects of different types of coupling agents were different greatly, and the effect of zircoalurninate(Y) was the best, the hygroscopicity and compressive strength of ammonium phosphate superfine powder modificated by 1.0% zircoaluminate(Y) were reduced by 64.2% and by 89.76% respectively compared with without being modificated; the hygroscopicity and compressive strength of the sample modificated with the composite of zircoaluminate(Y) and PVB were reduced by 72.9% and by 93.82%.The dry process was adopted to modificate ammonium phosphate superfine powder with the composite of zircoaluminate(Y), silicone oil and silicon dioxide.The compressive strength of the sample modificated was reduced by 91.04%.