以含轻烧白云石和氨废液为原料,采用含氨废液循环法制备碳酸钙晶须。利用扫描电镜(SEM)、X射线衍射仪(XRD)以及白度仪对碳酸钙样品进行表征,考察了循环次数、循环液中NH⁺₄和Ca²⁺浓度对制备的碳酸钙晶须回收率以及技术指标的影响。结果表明,采用循环法生产碳酸钙晶须能够使碳酸钙晶须总回收率由50%左右提高到70%左右,白度达到98,纯度(以CaCO₃计)也达到了98%以上。在不补加氨盐溶液的基础上循环4次之后,碳酸钙晶须长径比变小、形貌变差。

Calcium carbonate whisker is prepared from light burnt dolomite and spent ammonia liquid by recycling method.The samples are characterized by means of scanning electron microscopy (SEM),X-ray diffractometer (XRD) and whiteness meter.The effects of the number of cycles,and the concentrations of NH⁺₄ and Ca²⁺ in the circulating liquid on the recovery rate and technical indexes of calcium carbonate whisker are investigated.It is found that total recovery rate of calcium carbonate whisker can be increased from 50% to 70%,the whiteness is 98,and the purity (measured by CaCO₃) exceeds 98%.After cycling for 4 times without adding ammonia salt solution,the ratio of length to diameter of calcium carbonate whisker decreases and its morphology deteriorates.

凡远洋(1994-),男,硕士研究生,研究方向为无机钙镁功能材料,2291699326@qq.com。