Preparation of Ca(OH)₂ nanoparticles by impinging stream reaction precipitation method

Abstract In this paper, Ca(OH) 2 nanoparticles are prepared by impinging stream co‐precipitation method. The process of preparing nanoparticles by impinging stream is optimized. The influence of process variable, such as dispersant type, dispersant dosage, circulating flow rate, reactant concentration ratio of OH − and Ca 2+ , reaction temperature and circulation time, on the particle size of Ca(OH) 2 nanoparticle are investigated. The results show that the concentration ratio of reactants has a significant effect on the size of Ca(OH) 2 nanoparticles. The optimal process conditions are obtained by single factor experiment, PEG6000, 3.3% dispersant dosage, Q = 1000 L · h −1 , C = 1.88, T = 46.68°C and t = 60 min. The average particle size of Ca(OH) 2 nanoparticles prepared under these conditions is 107.67 nm. According to the microstructure analysis, the prepared Ca(OH) 2 nanoparticles samples have high purity and a good crystal structure. The powder dispersed with a marked hexagonal crystal shape and good thermal decomposition.