Vaterite calcium carbonate for the adsorption of Congo red from aqueous solutions
Vaterite calcium carbonate for the adsorption of Congo red from aqueous solutions
复制标题
DOI：
10.1016/j.jece.2014.09.017
复制
发表时间：
2014-12-01
影响因子：
7.7
通讯作者：
Sajab, Mohd Shaiful
中科院分区：
文献类型：
--
作者：
Chong, Kai Yin;Chia, Chin Hua;Sajab, Mohd Shaiful
研究了球形碳酸钙(CaCO3)对水溶液中刚果红(CR)的吸附性能。球泡石CaCO3是由乙二醇(EG)辅助沉淀法生产的，乙二醇起到稳定剂的作用，防止球泡石转化为其他晶型的CaCO3。用扫描电子显微镜、X射线衍射仪和傅立叶变换红外光谱等手段证明了生成的球泡石CaCO3的晶体结构。在pH值为5时，球泡石CaCO3的Zeta电位最高为15.2 mV。批量吸附研究表明，CR在球泡石CaCO3上的吸附依赖于不同的参数，如pH、染料初始浓度和温度。吸附等温线数据与Langmuir等温线模型高度吻合，而吸附动力学数据较好地符合准二级模型。吸附动力学实验表明，在pH为5、吸附剂用量为0.2g、吸附浓度为100 mg/L、温度为25℃的条件下，碳酸钙的最大吸附容量为32.60 mg/g。(C)2014爱思唯尔有限公司。保留所有权利。
The present study describes the evaluation of vaterite calcium carbonate (CaCO3) for the adsorption of Congo red (CR) from aqueous solution. Vaterite CaCO3 is produced via a precipitation method assisted by ethylene glycol (EG), which acts as stabilizer to prevent transformation of vaterite to others polymorphs of CaCO3. The crystal structure of vaterite CaCO3 formed was proven by SEM, XRD and FTIR. The highest zeta potential of the vaterite CaCO3 was 15.2 mV, which was obtained at pH 5. Batch adsorption studies illustrated that the adsorption of CR to the vaterite CaCO3 was dependent on different parameters, such as pH, initial dye concentration and temperature. The adsorption isotherm data were highly consistent with Langmuir isotherm model, while the adsorption kinetics data fitted better to the pseudo-second-order model. The maximum adsorption capacity of the CaCO3, 32.60 mg/g, was obtained from the adsorption kinetic experiment under adsorption conditions, pH 5, adsorbent dose 0.2 g, adsorbate concentration 100 mg/L and temperature 25 degrees C. The adsorption of CR on the CaCO3 was proven to be endothermic and non-spontaneous in nature. (C) 2014 Elsevier Ltd. All rights reserved.