ABSTRACT

The coal fly ash (CFA) in the present study contains a high content of gallium, which is categorized as a strategic metal. Gallium extraction from CFA is an important step toward its reutilization. Two different processes for gallium extraction were systematically investigated and compared. The effects of mixed acid, microwave power, microwave digestion time, the amount of HNO₃, HF, and HCl were studied. The results revealed that although both open wet digestion and microwave-assisted digestion could successfully leach gallium, the former method consumed a longer time. The microwave-assisted digestion was a time-saving way but required the use of HCl. Compared to previous studies, the processes proposed in this article can greatly reduce environmental pollution and cost as they halved the use of acids.

摘要

本研究中的粉煤灰 (CFA) 含有高含量的镓，被归类为战略金属。从 CFA 中提取镓是其再利用的重要一步。系统地研究和比较了两种不同的镓提取工艺。研究了混合酸、微波功率、微波消解时间、HNO ₃、HF、HCl用量的影响。结果表明，虽然开放式湿法消解和微波辅助消解都可以成功浸出镓，但前一种方法消耗的时间较长。微波辅助消解是一种节省时间的方法，但需要使用 HCl。与以前的研究相比，本文提出的工艺可以大大减少环境污染和成本，因为它们将酸的使用量减少了一半。