Comparison of the defluoridation efficiency of calcium phosphate and chitin in the exoskeleton of Antarctic krill     

WANG Zhangmin  YIN Xuebin 《极地研究(英文版)》2012,(3):149-154

Calcium （Ca）, phosphorus （P）, and chitin are the main components of the exoskeleton of krill. Defluoridation of a solution of sodium fluoride （NaF） using calcium phosphate （Ca3（PO4）2） and chitin as defluoridation agents was studied. Orthogonal experiments were designed to find the optimum reaction conditions for defluoridation, to obtain the maximum defluoridation efficiency and fluoride removal capacity of calcium phosphate and chitin. At the same time, a comparison of the capacity of the two defluoridation agents was made. The results suggest that calcium phosphate has a far greater capability than chitin for the removal of fluoride （F） from water under similar reaction conditions. It is also suggested that Antarctic krill is likely to adsorb fluoride via compounds such as calcium phosphate, hydroxyapatite, and other compounds of Ca and P with the general form （Ca, X）x（PO4, HPO4, Y）y（OH, Z）z, in addition to chitin.  相似文献   

凹凸棒粘土的除氟作用研究   总被引：7，自引：1，他引：7  

孙承辕  季峻峰 《高校地质学报》1997,3(4):400-414

凹凸棒粘土主要由坡缕石组成，后者为发育有一系列孔道的层链状硅酸盐矿物，具有很强的吸附能力，凹凸棒粘土的吸氟作用实验表明，其吸氟量随着溶液中氟离子浓度的提高而增加，在酸性含氟溶液中，凹凸棒粘土对溶液中氟的吸附量及溶液的降氟率都明显增加，而在碱性含氟溶液中，凹凸棒粘土对溶液中氟的吸附能力则大大降低，甚至不吸附。  相似文献   

蒙脱石降氟作用的实验研究   总被引：6，自引：1，他引：6       下载免费PDF全文

王洪涛季峻峰  刘连文 《岩石矿物学杂志》2003,22(1):71-73

实验表明蒙脱石吸附氟的能力与溶液的PH值呈显著的负相关关系：在较低PH值条件下，蒙脱石的吸氟量较大，具有显著的降氟作用；而对中性—碱性溶液来说，蒙脱石对氟的吸附能力则大大降低，基本不具吸氟能力。蒙脱石的吸氟量还与其用量及含氟溶液的浓度有关。吸附原因一方面是由于体系PH值降低，导致其表面带正电荷而吸附F^-；另一方面，随着NaF浓度升高，蒙脱石的双电层变薄，体系ξ电势减少，发生絮凝作用，并携带F^-沉淀下来。另外，F^-与OH^-的离子交换作用也是酸性条件下蒙脱石吸氟的一个重要原因。  相似文献