电石渣制备纳米晶碳酸钙的液相法工艺研究

文章研究了以氯化铵为提取液,利用液相法从电石渣中提取钙的工艺条件,并利用提取的钙与碳酸铵反应,成功制备出了纳米碳酸钙;从降低生产成本与提高产品质量出发,设计了一个二级循环浸取工艺,从而成功实现了氯化铵在整个制备过程中的循环利用,并达到环保的目的;该工艺中钙的提取率可达91.43%,产品碳酸钙的纯度与白度分别为99.93%与98,符合国家标准;X射线粉末衍射(XRD)结果表明,产物为纯净的方解石型碳酸钙;透射电子显微镜(TEM)显示产物的粒径为30 nm左右。

Preparation of calcium carbonate nanocrystallites from the calcium carbide residue by the liquid-state method

Processes of extracting calcium from the calcium carbide residue by the liquid-state method with ammonium chloride were studied,and nanocrystallites of calcium carbonate were prepared successfully by the reaction of the obtained calcium chloride with ammonium carbonate.Taking cost-cutting into account,a recycling extracting process has been selected to recycle ammonium chloride and promote the pureness of the resultant.Results of chemical analyses show that with a yield of(91.43%),the product prepared by this process is of the purity of 99.93 % and the brightness of 98 and can reach the standard of HG/T2776-1996.The patterns of X-ray powder diffraction(XRD) indicate that the product is pure calcium carbonate of calcite,and micrographs of transmission electron microscopy(TEM) confirm that the diameter of the calcium carbonate particle is about 30 nm.