(1. 武汉工程大学 化学与环境工程学院，武汉 430200；
2. 武汉工程大学 兴发矿业学院，武汉 430000)
摘 要: 风化壳淋积型稀土矿原地浸矿中产生大量残留铵盐，其缓慢释放对矿区周边环境造成严重污染，实时测定残留铵盐在矿体中的分布对于残留铵盐的高效处理意义重大。本文旨在筛选一种快速残留铵盐洗脱液，并结合氨气敏电极检测实现风化壳淋积型稀土矿中残留铵盐的实时检测。为此，研究了NaCl、KCl、CaCl2、NaOH、KOH、Ca(OH)2、Na2CO3、K2CO3溶液对残留铵盐的洗脱过程和脱除率。结果表明：三种金属的碱溶液对残留铵盐的洗脱速率和效果均高于碳酸盐和氯化物。在三种碱溶液中，NaOH对残留铵盐的洗脱在10 min内完成，洗脱率为90%，并且洗脱液无需再经pH调节，可直接采用氨气敏电极测定 浓度，方便快捷。采用NaOH洗脱-氨气敏电极检测联合法可实现稀土矿中残留铵盐的高效检测。
关键字: 风化壳淋积型稀土矿；残留铵盐；洗脱；实时检测
（1. School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430200, China;
2. Xingfa School of Mining Engineering, Wuhan Institute of Technology, Wuhan 430000, China）
Abstract:Large amount of ammonium salt was remained in the weathered crust elution-deposited rare earth ore (WCEDREO) during the in-situ leaching process, and the slow release of these ammonium salt would cause serious pollution to the surrounding environment of the mining area. Real-time detection of the distribution of residual ammonium salt is significant for efficiently treating of the residual ammonium salt. The aim of this paper is to screen a rapid residual ammonium salt eluent and realize the real-time detection of residual ammonium salt in WCEDREO with ammonium gas sensitive electrode. Desorption process and efficiency of the residual ammonium from the WCEDREO by different eluents, including NaCl, KCl, CaCl2, NaOH, KOH, Ca(OH)2, Na2CO3 and K2CO3 solutions, were studied. The results show that alkaline solutions of the three metals have faster elution rates and higher elution efficiencies than those of chloride and carbonate. Among the three alkaline solutions, NaOH solution shows a fast elution process with efficiency of about 90%. Moreover, the concentration of eluted ammonium in the effluent can be conveniently determined by ammonium gas sensitive electrode without further pH adjustment in this system. Based on this investigation, the residual ammonium salt in a rare earth ore can be rapidly determined by the combination method of NaOH elution and ammonium gas sensitive electrode test, which provides basic data for the residual ammonium treatment.
Key words: weathered crust elution-deposited rare earth ore; ammonium salt; eluent; real-time detection
