胞外多糖调控碳酸钙结晶的研究

Investigation of CaCO_3 Crystallization Induced by Extracellular Polysaccharide

以黄原胶和韦兰胶为模板,在CaCl2-Na2CO3体系中调控合成CaCO3晶体。利用电导率法研究了黄原胶与韦兰胶模板与Ca2+之间的相互作用,同时研究了黄原胶和韦兰胶的浓度以及结晶时间对CaCO3晶体结构及形貌的影响。分别用X射线衍射(XRD)、扫描电镜(SEM)对CaCO3晶体的晶型和形貌进行了表征。结果表明,黄原胶和韦兰胶调控下得到的CaCO3晶体是方解石和球霰石的混合体。韦兰胶溶液中得到了球形产物,黄原胶溶液中得到球状和花状产物。随着结晶时间的延长,球霰石不断向方解石转变。

Calcium carbonate was prepared by the CaCl2-Na2CO3 solution in the presence of xanhtan gum and welan gum as template.The interaction between extracellular polysaccharides and Ca2＋ was confirmed by the method of conductivity.The effects of concentration of xanthan gum and welan gum,crystallization time on the morphology of calcium carbonate were also studied,respectively.The products were analyzed by FT-IR,XRD and SEM,respectively.The results showed that calcium carbonate prepared in xanthan gum and welan gum solution were the mixture of calcite and vaterite.Products in welan gum solution were spherical.Spherical and flower-like calcium carbonate particles were obtained in xanthan gum solution.The vaterite gradually transformed to calcite with the time.