Ruyun Bai,Yong Huang,Sining Li,Changzhi Su,Huan Li,Qiushuang Cui,Wen Liu,Hanyu Wei,Yi Si
Xinjiang is one of China’s most significant energy bases, and the generated fly ash (FA) contains a high concentration of metallic elements that can be used as a valuable resource. In this study, we looked into a roasting-acid leaching process technique for efficiently extracting gallium metal (Ga) from FA, employing sodium fluoride (NaF) as the roasting auxiliary and citric acid inzter (C6H8O7) acid leaching. After high-temperature activation by NaF, the glassy phase of FA was converted into silica aluminate with excellent acid solubility, and Ga was extracted from FA via acid leaching. The effects of optimal roasting and acid leaching process conditions on the Ga leaching rate were investigated. The results showed that it exhibited 83.71% Ga extraction under the conditions of a roasting temperature of 850 °C, FA-NaF coordination ratio of 1:0.5, roasting time of 10 min, C6H8O7solution concentration of 1.75 mol/L, ratio (S/L) of 1:15, acid leaching temperature of 100 °C, and acid leaching time of 1 h. The results also indicated that it was possible to obtain a higher extraction efficiency for the Ga extracts under the conditions of roasting temperature of 850 °C and FA-NaF coordination ratio of 1:0.5.
Keyi Xu,Lihui Gao,Shulei Li,Hongzhao Liu,Yanhong Liu,Wenfeng Pan
The extraction of gallium using amidoxime chelating resin has demonstrated extensive industrial applications. However, repeated desorption cycles lead to resin deactivation, and untreated waste resins may pose environmental risks. This study conducted deactivation diagnosis on waste resin, characterizing its surface morphology and functional group distribution through FSEM, XPS, and FTIR analyses. The deactivated resin exhibited three key characteristics: Surface contamination by impurities, oxidation of amidoxime groups into carboxylic acids and hydroxamic acids, and occupation of Ga(III) adsorption sites by competing ions. To address these issues, a regeneration strategy combining ultrasonic cavitation for impurity removal with amidoximation of residual nitrile groups was proposed. Under the conditions of Ga(III) concentration 200 mg/L, pH 12, and liquid-solid ratio 100 mL/g, the regenerated resin demonstrated an adsorption capacity of 12.21 mg/g, which was 2.71 times that of new resin. The adsorption process of the regenerated resin conforms to the Langmuir isotherm. The theoretical maximum adsorption capacity of Ga(III) was calculated to be 34.78 mg/g under alkaline conditions. XPS analysis confirmed the critical role of oxygen-containing functional groups in Ga(III) adsorption. This research provides novel insights into resource utilization of the waste resin and demonstrates significant potential for Ga(III) extraction applications.
危险品化学品经营许可证（带存储）