摘要
A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by complexation.Polyaluminum chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield economically.In the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis operations.It was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 hr.The Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and TGA.The results showed that the purity of the Al_(30)product could exceed 92%.
A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by complexation.Polyaluminum chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield economically.In the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis operations.It was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 hr.The Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and TGA.The results showed that the purity of the Al_(30)product could exceed 92%.
基金
supported by the National Natural Science Foundation of China (Nos. 21507149, 51338010)
the National Water Pollution Control and Treatment Science and Technology Major Project (No. 2015ZX07406005-002)
