铁成分对硫化锌精矿的半导体性质及化学反应性的影响

硫化锌精矿(以下简称精矿)除含有主要元素锌与硫外,还含有其它元素,尤其是含有相当多的铁。在湿法处理精矿时,其铁成分的行为取决于铁的矿物存在形式。精矿中的铁可以铁闪锌矿(Zn,Fe)S)、黄铁矿、黄铜矿的形式存在。铁闪锌矿的铁含量可在很大的范围内变化,其物理化学性质也随铁含量而变化,因此对精矿的湿法直接处理产生很大的影响。本文研究出一种可靠的、确定精矿矿物组成的化学分析方法,着重于测定铁在精矿各矿物中的分布,及铁闪锌矿铁含量的变化规律。在此基础上,实验研究了精矿中的铁(尤其是铁闪锌矿中的铁)对精矿的半导体性质的影响规律,应用半导体电化学原理讨论了精矿铁含量对精矿的直接浸出(常压、硫酸介质)的影响机理。

EFFECT OF THE IRON CONTENT OF ZINC SULPHIDE CONCENTRATES ON THEIR SEMI-CONDUCTIVITY AND CHEMICAL REACTIVITY

The mineralogical form in which the iron occurs in the concentrates of zinc sulphide, and the effect of the iron on direct leaching of the concentrates are subjects of this paper. The iron in the zinc sulphide concentrates mainly comprises marmatite and pyrite. Two original experimental methods have been developed: 1) A procedure of mineralogical analysis of zinc sulphide concentrates which permits to reliably determine the proportion Fe/Zn of marmatite in each concentrate and the proportion of marmatite in each of the concentrates. 2) Measurement of electric conductivity of the concentrates ( pulverous, heterogeneous materials ) . The correlations have been established between the values of the electric conductivity of the concentrates, the iron content of their marmatite and the leachability of the concentrates in H_2SO_4-Fe_2(SO_4)_3-media. The presence of iron in marmatite increases sensitively the electric conductivity of concentrates and favours the development of the electrochemical dissolution of zinc sulphide with direct production of elemental sulphur. A simple and fast test leading to the determination of electric conductivity of the concentrates enables to estimate the reactivity of the concentrates.