砷是很多种含金的硫化矿石和精矿中常见的伴生组分,在自然界中主要以砷黄铁矿的形式存在。由于砷黄铁矿和常与其伴生的黄铁矿对金的氰化浸出会产生有害影响,所以需要对含砷的金矿进行预先氧化焙烧。这时,大部分呈有毒而又难以回收的三氧化物形式存在的砷就转入升华物中。但其中一部分虽然经过多段焙烧,仍以金属砷酸盐形式残留在烧渣中,因而在以后氰化处理时使金的浸出率降低,氰化物耗量增加。在用火法冶金处理烧渣时,以硫化物形式残留的砷就转入气相并污染环境。众所周知,回收三氧化二砷以及对含这种化合物的气体作净化 Arsenic is a common species associated with many gold-bearing sulphide ores and concentrates and is found mainly in the form of arsenic pyrites in nature. Since arsenopyrite and its associated pyrites have a detrimental effect on cyanide leaching of gold, pre-oxidation roasting of arsenic-containing gold ore is required. At this moment, most of the arsenic in the form of the trioxide, which is poisonous and difficult to be recovered, is transferred to the sublimate. However, although some of them are still roasted in the form of metal arsenate, they still remain in the cinders in the form of metal arsenate, so that the leaching rate of gold decreases and the consumption of cyanide increases during the subsequent cyanidation. In the pyrometallurgical treatment of slag, the residual arsenic in the form of sulfide is transferred to the gas phase and pollutes the environment. It is well-known that the arsenic trioxide is recovered and the gas containing the compound is purified