Preparation And Characterization Of Cuprous Chloride Micro-crystallization

Cuprous chloride is widely used as a catalyst in organic synthetic industry. Many organic chemicals can be produced by its catalysis. Besides as decolourant,desulfurizer and release agent in petrochemical industry, cuprous chloride is also greatly used in areas of metallurgical industry, electroplating industry, medical chemistry, agricultural chemical project, battery industry, rubber industry, etc. Presently there are many preparation methods, but producing the epigranular, stable cuprous chloride of high activity is never reported. Hereby, the influencing factors of CuCl granularity, surface topography, inoxidizability are studied in this experiment.The condition of thermostatic water heating is used in this experiment first, copper sulfate is deoxygenized into cuprous chloride by sodium sulfite, the influencing factors of the yield coefficient and purity quotient of cuprous chloride are important studied, and get the best technology of producing cuprous chloride; Then under the best technology, the influencing factors of CuCl granularity, surface topography, inoxidizability by microwave radiation crystallization are important studied in this experiment. The experiment research shows:1.When copper sulfate is deoxygenized by sodium sulfite under the condition of thermostatic water heating, it is technically feasible to produce cuprous chloride of high yield coefficient and high purity using sodium carbonate to adjust the pH of the reaction solution. The best technology for producing cuprous chloride of high yield coefficient and high purity is: consistency of copper ion in the reducing solution is 100g·L-1; reduction temperature is 40℃; reduction period is 120min; quantity of sodium sulfite is 1.3 times as much as the theoretical quantity; quantity of sodium chloride is 1.1 times as much as the theoretical quantity; pH=2; reducing solution composition is: V(Na2SO3)/V(Na2CO3)=2 : 1 for the former reducing solution; V(Na2SO3) /V(Na2CO3)=3:1 for the latter reducing solution, and volume of the former reducing solution/ volume of the latter reducing solution =8:2;The charging way is 50minutes for the former reducing solution charging period and 10minutes for the latter period on the condition of 1 hour's total charging period. With the best technology above for producing cuprous chloride, it can reach the yield coefficient of 94.8% and purity of 98.9%.2. There still exist superfluous sodium chloride and abounding product of sodium sulfate which must be reprocessed and purified in the deoxygenized solution. The best technology for reprocessing sodium sulfate in the deoxygenized solution is: First the deoxygenized solution is pretreated by NaOH and then get vacuum crystallization under vacuum level of 0.06～0.08MPa and temperature of 50～70℃. The sodium sulfate crystals produced is 166g and the maximum crystallizing rate ran up to 87.4%, the crystal parent solution of Na2SO4 are reused in batching copper sulfate solution.3.Cuprous chloride produced under thermostatic water can attain high yield coefficient and high purity. However, it is of low activity, wide size distribution and big mean particle size. It is easy to be oxidized because its crystal shape is not perfect and with oxygen hollow space on the crystal face. Therefore, microwave radiation maturing crystallization is applied to produce the micron cuprous chloride and the best technology is: the microwave power is from high to low (from 800W to 1500W); microwave radiation period is 2 hours; pH=2; consistency of copper ion is 120g·L-1; dispersant of PVP and covertures of tributyl phosphate (TBP) are added. The cuprous chloride produced is epigranular, with mean particle size of 0.74μm and good dispersivity. The crystal shape is perfect and there are no flaws on the crystal faces so the inoxidizability is strong.4.Compared with thermostatic water heating, microwave radiation heating obviously could refine, homogenize the crystal grain, and also inhibit their growth. The individual crystal grain of cuprous chloride produced by microwave radiation heating appears standard tetrahedral shape. The crystal shape is perfect and without oxygen hollow space on the crystal faces so the impurity content is low and the inoxidizability is strong. Besides, the crystallizing period is shorter but the crystal shape, lattice structure and phase structure are not changed by the microwave radiation heating.