School of Environment and Resources,Engineering Research Center of Ministry of Education for CO2 Emission Reduction and Resource Utilization,Shanxi University
Shanxi Stone Age New Materials Technology Co.,Ltd.

PVC、乙烯等工业生产过程产生的电石渣大量堆存造成严重的环境污染和资源浪费。电石渣酸浸提钙是制备纳米碳酸钙等钙基高附加值化学品的前置技术,但酸浸过程不可避免造成电石渣中杂质离子的浸出,严重影响Ca2+的纯度。为了降低杂质离子的浸出,对比HCl和NH4Cl2种浸取剂体系,利用单因素试验、正交试验和各种表征研究氯钙物质的量比、温度、搅拌速率和搅拌时间等不同浸取条件对Ca2+及Al3+、Mg2+和Fe3+杂质离子浸出的影响规律。结果发现:HCl浸取体系Ca2+转化率高于NH4Cl体系,浸取条件对Ca2+转化率的影响程度为氯钙物质的量比>时间>温度>搅拌速率;浸取剂用量是2种浸取剂体系杂质离子浸出最大的影响因素,其他因素影响相对较小。此外,HCl浸取体系杂质离子浸出量和浸出速度远高于NH4Cl体系,HCl浸取体系可将Al3+、Mg2+和Fe3+浸出,而NH4Cl体系仅可浸出Al3+和Mg2+,并且其质量浓度远低于HCl体系。

The industrial processes of PVC,ethylene,and so on produced a significant amount of calcium carbide slag,leading to severeenvironmental issues and resource wastage. Acid leaching is a pre-treatment technique employed for extracting calcium from calciumcarbide slag to produce high-value calcium-based chemicals like nano-calcium carbonate. However,impurity ions present in the slag areinevitably leached during this process,adversely affecting the purity of Ca. In the present study,HCl and NH4Cl leaching systems werecompared and the effect of various leaching conditions (molar ratio,temperature,agitation rate and time) on the leaching efficienciesof calcium and impurity ions (Al,Mg and Fe) was investigated. One-way experiments,orthogonal experiments,and analysis usingdifferent characteristics were conducted. The findings revealed that the conversion rate of Ca was higher in the HCl system compared tothe NH4Cl system. Amongst different leaching conditions studied here,molar ratio had the most significant influence on Ca conversionrate followed by time > temperature > stirring rate. Leaching agent dosage emerged as the most influential factor affecting ion leaching inboth systems while other factors exhibited small or even negligible effects. The HCl leaching system can leach Al,Mg and Fe,while theNH4Cl system can only leach Al and Mg,and its concentration is much lower than the HCl system.

吕梁市科技计划资助项目(2021RC−2−12);国家自然科学基金资助项目(22278254)

晋鹤宁,张鹏云,张亚斌,等.不同酸浸过程电石渣中杂质离子随Ca2+浸出特性[J].洁净煤技术,2024,30(11):123−129.

JIN Hening, ZHANG Pengyun, ZHANG Yabin, et al. Leaching characteristics of impurity ions with Ca2+ in calcium carbide slag during different acid leaching processes[J].Clean Coal Technology,2024,30(11):123−129.