An environmentally friendly and high current efficiency acid mist inhibitor for zinc electrowinning

Abstract

Acid mist inhibitor is an effective additive for suppressing the generation of acid mist during electrowinning process. However, the traditional acid mist inhibitor has a low current efficiency, leading to high energy consumption. Thus, novel acid mist inhibitors are crucial for the development of the electrowinning industry. In this paper, three new acid mist inhibitors (Famigo® FS-101, Famigo® FS-301, and Famigo® FS-401) are used in zinc electrowinning process, while the mechanism of action in suppressing the generation of acid mist is characterized by the volume of bubble attached on the cathode surface and surface tension. The impacts of the concentration of the acid mist inhibitors on the bath voltage, current efficiency, power consumption, and electrochemical properties, as well as the enhancement mechanism on the current efficiency, are studied. The obtained results demonstrate that an adequate concentration of Famigo®FS-101, Famigo®FS-301, and Famigo®FS-401 allows to increase the cathode current efficiency and decrease the energy consumption, from 3219 kWh t−1 in zinc electrolyzer to 2948 kWh t−1, 3090 kWh t−1, and 2884 kWh t−1 using a concentration of 5 mg l−1 of Famigo®FS-101, Famigo®FS-301, and Famigo®FS-401, respectively. The proposed inhibitors have high acid mist inhibition efficiency and current efficiency in the zinc electrowinning process. Furthermore, if engineered, they may contribute to the development of the electroposition industry.