硫化银碱性水浆直接加氢还原制备金属银

Direct Preparation of Metallic Silver by Hydrogen Reduction of Basic Slurry of Silver Sulfide

提出了一种新的从硫化银直接制备金属银的湿化学方法. 采用硫化银的碱性水浆在高压釜中直接加氢进行还原. 借助XRD, SEM和化学反应分析等手段, 对硫化银浆化氢还原过程中的影响因素进行了研究. 结果表明： 通过添加少量的催化剂和适量的ZnO作为还原助剂, 硫化银在220 ℃, Ph≈12, PH2=2～3 Mpa的条件下反应4 h, 其中银的还原率可以达到95%左右. 所得的产物是呈分散状态的粉体.

A new wet-chemical method for producing metallic silver directly from silver sulfide was proposed. The basic silver sulfide slurry was reduced directly by hydrogen in autoclave. The influence factors on the hydrogen reduction process of silver sulfide slurry were studied by XRD, SEM and chemical reaction analysis. The results show that 95% of silver in silver sulfide can be reduced by adding a little amount of catalyst and a certain amount of ZnO as an assistant reducing agent with hydrogen under the conditions of 220℃, pH= 12.0, PH2=2-3 MPa for 4 h. The powders obtained are dispersive particles.