Abstract: The solubility of annabergite is characterized by the concentrations of Ni and As. TCLP tests showed that there was a little poorly crystalline product in the annabergite synthesized by the authors.The long-term solubility tests were conducted to evaluate the stability of resultant product and the results showed that the dissolution of annabergite gradually reached equilibrium after 15 days. The solubility was strongly dependant on the pH of the medium with the concentrations of Ni and As decreasing remarkably with increasing pH.The lowest concentrations were 48 mg•L^-1 As and 0.2 mg•L^-1 Ni at pH 9.Nickel and arsenic of annabergite dissolved at the same step［n(Ni)∶n(As)=1.5］with the theoretical figure of molecular formula, but the Ni/As molar ratio was much lower than the theoretical figure because of Ni(OH)₂ precipitated. The solubility of annabergite was much lower than that of Nishimura et al’s.

摘要： 结晶型砷酸镍的溶解性用溶液中的Ni和As的浓度来表征.TCLP实验结果表明Ni和As在溶液中的浓度随着实验重复次数的增加而显著降低，说明自制结晶型砷酸镍中含有部分非晶态物质.长期溶解性实验证明结晶型砷酸镍的溶解在15 d后达到平衡，并且随着pH值升高溶液中Ni和As浓度降低，在pH 9时达到最低的48 mg•L^-1 As和0.2 mg•L^-1 Ni，砷酸镍中的As和Ni在pH 3和pH 4时按分子式理论值n(Ni)∶n(As)=1.5同步溶解，而由于Ni(OH)₂的生成，在高pH值溶液中的n(Ni)∶n(As)远低于理论值1.5.实验结果表明本研究合成的结晶型砷酸镍比Nishimura等的更稳定，具有更低的溶解性.