摘要：
盐岩矿的水溶法开采是获得人类生活必需品和重要工业原料——盐的重要途径之一.在水溶法开采中,岩盐矿中的水溶性重金属会随着母液到达地表环境和后续的岩盐产品中,可能对地表环境造成污染和危害人体健康,故对岩盐矿中水溶性重金属的检测非常重要.岩盐矿中的水溶性铜铅锌镉含量较低,而盐分含量过高,过高的盐分含量会影响ICP-OES的雾化效率,故很难用ICP-OES直接测量重金属含量.本文以巯基棉为吸附材料,从溶液pH、洗脱液浓度、洗脱液体积等方面研究了分离富集岩盐矿中水溶性铜铅锌镉的实验条件.结果表明,在pH =7的介质中,巯基棉对铜铅锌镉有良好的吸附性能,被吸附的铜铅锌镉可用7 mL盐酸(15％)定量洗脱,溶液中的钠对吸附无明显影响.对解吸后的溶液,铜铅锌镉的回收率均≥92.2％,钠回收率仅0.04％,基本实现了铜铅锌镉与钠的分离,达到了ICP-OES检测要求.%Solution mining of rock salt is one of the important methods to obtain salt,which is a necessity of human life and an important raw material of industry.In solution mining,water-soluble heavy metals within rock salt will migrate to the surface environment with mother solution and remain in subsequent salt products,which may contaminate the surface environment and endanger human health.Thus,it is of great importance to analyze water-soluble heavy metals in rock salt.However,water-soluble heavy metals,such as Cu,Pb,Zn,Cd,have much lower abundances than salt.The high content of salt will affect the atomization efficiency of Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES),making it difficult to directly quantify these metals.In this study,sulfhydryl cotton was employed as the absorbent to separate and enrich Cu,Pb,Zn,Cd in rock salt.Experimental conditions such as pH,concentration and volume of eluent were optimized.The results indicated that good adsorption efficiency was achieved at pH 7,and adsorbed metals could be quantitatively eluted with 7 mL 15％ HC1.Meanwhile,Na had no influences on the adsorption or desorption processes.The recoveries of Cu,Pb,Zn and Cd in desorbed solution are above 92.2％,and only 0.04％ for Na,realizing the separation of heavy metals from Na and meeting the requirements for the detection of heavy metals by ICP-OES.
