摘要
在湿法冶金工艺中,近几十年来使用金属硫化沉淀代替氢氧化物沉淀取得了突破。选择此法的理由是可在相对较低的pH值下,达到较高的金属沉淀率;硫化物沉淀的难溶性;有利沉淀的特点和稳定的金属硫化物。然而,当选择金属硫化物沉淀的路线,会遇到各种困难,本文描述了其中两个。第一个问题是,这些金属硫化沉淀工艺,具有低溶解度和过饱和度的特点,由于均相成核机理、聚合和磨损,易于形成微粒。第二个问题是,在硫化物局部浓度过高的地方,硫化物过量可导致形成水溶的多硫化物,消耗硫化反应剂,影响金属去除效果。
In hydrometallurgical processes, the use of metal sulphide instead of hydroxide precipitation has gained prominence in recent decades. The arguments for its preferential use are based on the high degree of metal removal at relatively low pH values; the sparingly soluble nature of sulphide precipitates; favourable dewatering characteristics and the stability of the metal sulphides formed. However, when choosing a metal sulphide precipitation route, various difficulties are encountered, two of which are described in the current work. The first issue is that these metal sulphide processes, dominated by low solubilities and high supersaturation levels, favour the formation of fine particles due to the dominant mechanisms of homogeneous nucleation, aggregation and attrition. The second issue is that, in areas of high local sulphide concentration, the excess sulphide can lead to the formation of aqueous polysulphide complexes, which consume the sulphide reagent and compromise the metal removal.
出处
《中国有色冶金》
北大核心
2009年第4期6-10,22,共6页
China Nonferrous Metallurgy
关键词
硫化铜
硫化镍
沉淀
混合硫化物
金属硫化物
微粒
多相反应器
颗粒的形成
copper sulphide
nickel sulphide
precipitation
mixed sulphide
metal sulphide
fines
muhiphasereactor
particle formation
