利用电石渣液相法制备纳米碳酸钙

Preparation of Nano Calcium Carbonate from Calcium Carbide Residue by Liquid Phase Process

以电石渣为原料、氯化铵溶液为浸取剂、碳酸铵溶液为碳酸化试剂、柠檬酸为晶形控制剂,采用液相法制备了高纯度的纳米级碳酸钙。考察了多种因素对反应的影响,通过 X 射线衍射仪和扫描电子显微镜对制得的碳酸钙进行表征。确定了最佳的工艺条件:碳酸化过程浸出液 Ca^(2+)浓度为0.6 mol/L,柠檬酸与碳酸钙质量比为0.03,碳酸化反应温度为12℃。制得的碳酸钙粒径为40～60 nm,为纯净的方解石型晶型。

Nano calcium carbonate with high purity was prepared from calcium carbide residue by a liquid phase process using ammonium chloride as extraction agent and ammonium carbonate as carbonation agent. The effects of several factors on the reaction were investigated. The calcium carbonate was observed by X-ray powder diffraction device （XRD） and scanning electron microscopy （SEM）. The optimum process conditions were determined as follows： lixivium Ca^2＋ concentration 0.6 mol/L, citric acid/calcium carbonate 3% in mass, and carbonation temperature 12 ℃. The product is a pure calcium carbonate of calcite with 40 -60 nm of particle diameter.