紫外光分解银硫代硫酸盐络合物的研究

Study on photolysis of silver thiosulfate complex by UV

银是一种贵金属,在自然界中少数以单质形式存在,多数以化合物形式存在于银矿石中。在含银的化合物中,硫化银(Ag2S)是一种化学稳定性高,窄能带半导体材料,具有较好的光电、热电性能,而被广泛用于光电池、光电导元件、红外检测器和快离子导体等领域。目前银矿石中银的提取往往采用氧化焙烧-硫酸浸出的方法,随着研究的深入近些年来已有学者提出一种全湿法流程,即研究利用无氨硫代硫酸盐体系在弱碱性条件下提取银矿石中的银,应用该方法会产生大量的含银硫代硫酸盐配合物溶液。为了有效回收利用银资源,同时结合硫代硫酸盐对紫外光敏感的性质,研究了在不同银浓度、不同硫代硫酸盐浓度、不同初始pH条件下银硫代硫酸盐配合物的分解过程,并对紫外光条件下的分解产物进行表征。实验结果表明,配合物可以在紫外光条件下发生分解生成硫化银沉淀从而实现银的回收。

Silver is a kind of precious metals,a few of which exist in nature as elemental substance,and most of them exist in silver mineralogy as compound.Among the compounds containing silver,silver sulfide(Ag2 S)is a kind of semiconductor material with high chemical stability and narrow band,which has good photoelectric and thermoelectric properties.It is widely used in the fields of photocell,photoconductive element,infrared detector and fast ion conductor.It is effective for silver extraction in ore with oxidizing roasting-sulfuric acid leaching method.Recently scholars have put forward a full wet process,namely the use of solution without ammonia thiosulfate system under the condition of weak alkaline extraction silver in ore,and the application of this method will produce large amounts of silver thiosulfate complex solution.In order to effectively recover and utilize silver resources,and in combination with the sensitivity of thiosulfate to ultraviolet light,the photolysis process of silver thiosulfate complexes under different silver concentrations,different thiosulfate concentrations and different initial pH values was studied,and the precipitation products under ultraviolet light were characterized.The results show that the complex can be photolyzed under ultraviolet light to form silver sulfide precipitate.