利用羧酸盐的水解脱羧反应合成纯文石晶须

Preparation of Pure Aragonite Whiskers by Hydrolysis and Decarboxylation of Carboxylate

采用三氯乙酸和氢氧化钙为起始材料，分别配制0．05—1．0mol·L^-1不同浓度的三氯乙酸钙（CaTca）溶液，然后在90℃恒温水解脱羧5h。采用X射线衍射仪（XRD）和电子扫描电镜（SEM）对反应产物进行测试。结果表明，随CaTca浓度的增加，文石晶须的含量逐渐减小，但只要CaTca的浓度小于0．6mol·L^-1，均可获得纯度大于97％的文石晶须，晶须直径为4．5μm，长径比9—16。利用三氯乙酸盐的水解脱羧反应是一种合成文石晶须的简易而有效的方法。

An easy and simple method to prepare pure aragonite whiskers was introduced in this paper. First, the raw materials including trichloroacetate and calcium hydroxide were mixed by the mole ratio of 2 to I to prepare solutions of calcium trichloroacetate （CaTca） with different concentrations varying from 0.05 to 1.0 mol·L^-1 then the solutions of CaTca were hydrolyzed and decarboxylated at 90℃ for 5 hours,and the reaction products were characterized by powder XRD and SEM. It was observed that, though the percentums of aragonite whiskers slightly gradually decreased with the increase of CaTca concentrations in the solution, the reaction products were always nearly pure aragonite whiskers with percentums greater than 97%, if the CaTca concentrations were under 0.6 mol·L^-1 . The sizes of as - prepared aragonite whiskers were about 4-5μm in diameters with aspect ratios in the range of 9 to 16.