Lee Ye Hwan, Yang Heejae, Lee Sang Moon, Kim Sung Su
Department of Environmental Energy Engineering, Graduate School of Kyonggi University, 94-6 San, Iui-dong, Youngtong-ku, Suwon-si, Gyeonggi-do 442-760, Korea.
Department of Environmental Energy Engineering, Kyonggi University, 94-6 San, Iui-dong, Youngtong-ku, Suwon-si, Gyeonggi-do 442-760, Korea.
ACS Omega. 2020 Sep 15;5(38):24351-24355. doi: 10.1021/acsomega.0c02575. eCollection 2020 Sep 29.
Water and hydrochloric acid were employed as solvents to extract K and Ca from K- and Ca- rich cement kiln dust (CKD). It has been shown that hydrochloric acid effectively extracts Ca and K from CKD with efficiencies of more than 85 and 99%, respectively. On the other hand, water, as a solvent, selectively extracts K and Cl with an efficiency of 99%. The selectivity of Ca extracted using hydrochloric acid from treated CKD increased from 37 to 87%. Scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed that K and Cl were dominant on the surface of fresh CKD. After extraction with water, the portion of Ca increased more than twice, and Ca species became dominant. Thus, extraction of CKD with water is capable of selectively removing KCl, leaving Ca on the surface; hence, treated Ca-rich CKD can serve as a suitable raw material for mineral carbonation.
采用水和盐酸作为溶剂从富含钾和钙的水泥窑灰（CKD）中提取钾和钙。结果表明，盐酸能有效从CKD中提取钙和钾，提取效率分别超过85%和99%。另一方面，水作为溶剂，能以99%的效率选择性提取钾和氯。用盐酸从处理后的CKD中提取钙的选择性从37%提高到了87%。扫描电子显微镜和能量色散X射线光谱分析表明，新鲜CKD表面以钾和氯为主。用水提取后，钙的比例增加了两倍多，且钙物种占主导地位。因此，用水提取CKD能够选择性去除氯化钾，使钙留在表面；因此，处理后的富钙CKD可作为矿物碳酸化的合适原料。
