Lsss、ML制备及其溶金体系的研究

【作者】 党晓娥；

【导师】 兰新哲；

【作者基本信息】 西安建筑科技大学 ， 冶金物理化学， 2001， 硕士

【摘要】 本论文在回顾含硫试剂研究状况的基础上，对LSSS、ML试剂制备及其溶金体系进行了较系统的研究。结果表明：从充分利用原料S，Ca（OH）₂、降低成本、提高浸金率等出发，优化了LSSS体系；利用高效添加剂快速制备固体LSSS，利用固体LSSS溶解氧化制得的ML为白色易溶晶体，提高金的浸取率；通过不同ML的制备方法可以知道，起始浓度影响着氧化制备ML的进程。容量分析方法因为操作简单，准确度、精确度高、分离充分，分析能达到实践要求，是该体系的首选方法；研究Na₂SO₃作为体系的稳定剂，它阻碍S₂O₃^2-，S_x^2-的氧化；与LSSS体系中的S^2-以及浸出过程生成的元素硫作用，生成有效溶金成分S₂O₃^2-或S_x-1^2-，并且有助于 CuS、Cu₂S返溶；而且，它的加入，使Cu（NH₃）₄²⁺主要的氧化作用变为催化作用，促进金的大量溶解，对LSSS、ML体系起了很大的作用。在试剂消耗研究中，初步定量 S₂O₃^2-被吸附损失约占 8％；在不通空气未加SO₃^2-的情况下，S₂O₃^2-与铜氨发生氧化反应损失约32％，S^2-的氧化，使S₂O₃^2-增加近30％，弥补了S₂O₃²与铜氨发生氧化反应所造成的损失；不通空气加 SO₃^2-的情况下，S₂O₃^2-浓度增加8％，而SO₃^2-与S_x^义-起反应，便SO₃^2-消耗近67％；在加SO₃^2-不通空气条件下，氧化损失为 18％；在通空气，加 SO₃^2-的情况下，SO₃^2-消耗40％，而 S₂O₃^2-浓度增加76％，弥补了S₂O₃^2-氧化造成的损失，使浸金成分稳定；S_x^2-的消耗主要是分解生成S，S^2-与SO₃^2-发生反应生成S₂O₃^2-消耗；铜的消耗主要是生成蓝色结晶Na·［Cu（NH₃）₂（S₂O₃）₂］·4H₂O，带走 8％左右的铜，浸金过程生成的 Cu₂S和 CuS于氨性介质中，在SO₃^2-和O₂参与下逐渐返溶。这些研究成果对LSSS、MLSSS浸金工艺及条件的优化起了重要作用。更多还原

【Abstract】 On the basis of the comparative study of leaching gold by those sulfur-bearingreagents, this paper mainly deals with the preparation of LSSS and ML（Modified Lime-Sulfur-synthetic-Solution） and their leaching gold systems. The experiment results showthe optimal ratio in synthesizing LSSS is Ca（OH）₂: S: H₂O=1: 3: 50, by which caneffectively use the raw materials. Solid LSSS was quickly synthetic by using of highlyeffective additives. When Solid LSSS was dissolved and properly oxidized, ML wasobtained, which is a kind of white soluble crystal. Through comparing different methodsof preparing ML,it can be seen that the initial concentration of LSSS influenced,etc theoxidation process .Volumetric analysis is the first choice of LSSS system for itsadvantages of easy operation, high accuracy and precision and which fully meets thedemands of practice. Na₂SO₃ acted as stabilizer of LSSS system, it can effectivelyprevent the oxidation of S₂O₃^2- and Sx^2-,when SO₃^2- reacted with S^2- and element S inthe LSSS leaching gold system,S₂O₃^2- or S_x-1^2- will be obtained, which is be beneficial togold leaching components.Also,S₂O₃^2- is helpful for dissolving of CuS and Cu₂S. In thestudy of reagent consumption,S₂O₃^2- was absorbed by about 8 percent, on the conditionof without air and SO₃^2-, the oxidation consumption of S₂O₃^2- by copper ammonia ion is32 percent, at the same time the oxidation of S^2- makes the quantity of S₂O₃^2- increaseby 20 percent, which compensated the oxidation consumption of S₂O₃^2-. In the conditionswithout air and SO₃^2-, the concentration of S₂O₃^2- in LSSS increased by 8 percent,while the reaction of SO₃^2- with Sx^2- consummated almost 67 percent of S₂O₃^2-. In thecondition of venting air and adding SO₃^2-, the consumption of SO₃^2- is about 40 percent,while the concentration of S₂O₃^2- increased by 76 percent, which compensated the loss ofS₂O₃^2- and make the gold leaching system more stable. The consumption of Sx^2- is causedby the decomposition of Sx^2- to S, S^2-, which then reacted with SO₃^2- and resulted inS₂O₃^2-. Appearance of blue crystal Na·[Ca（NH）₃（S₂O₃）₂]·4H₂O in LSSS system caused 8percent of Copper consumption. In ammonia media and the Cu₂S and CuS obtainedduring leaching process will be dissolvable. All these studies play an important role inwinns the tectwoaror isssanu Mibetwsolu.更多还原