硅材料湿法提纯理论分析及工艺优化

介绍了中等规模太阳级硅粉的湿法提纯工艺，就硅粉回收率，硅粒尺寸及酸洗液浓度等重要工艺参数对杂质含量及提纯成本的影响进行了分析，讨论了高浓度酸萃取时“钝化现象”的机理并修正了理论模型。根据理论分析与实验数据进行工艺优化，为大规模湿示提纯太阳级硅材料提供了重要依据。     

从工业铝酸钠溶液中湿法除硫工艺研究

介绍了用铝酸钡从工业铝酸钠溶液中湿法除硫的试验结果,详细考察了时间、温度、铝酸钡添加量对除硫效果的影响,试验结果为工业生产提供了较完整的试验数据。     

以焙烧—湿法工艺从含金废料中回收金

针对紫金矿业集团黄金冶炼厂产出的含金废粒,进行了焙烧－湿法回收金的工艺研究。含金废料经焙烧去除炭质和有机物后,经氰化浸出、炭吸附回收金,金回收率可达90％以上,该工艺成本低,易实施,可获得良好的经济效益。     

基于改进即时学习算法的湿法冶金浸出过程建模

针对湿法冶金浸出过程中存在的多变量、非线性和多工况等问题,采用基于即时学习算法的最小二乘支持向量机建立浸出率的预测模型。将时间有序性引入到即时学习算法学习集的选取规则中以确定系统当前工作点的建模邻域,从而提高模型精度;引入累计相似因子以提高所建模型的实时性,并利用自适应相似度阈值来判定是否需要重新建立当前工作点的局部模型。将改进的建模方法应用到湿法冶金浸出过程浸出率的预测中,仿真结果表明,所建模型具有较高的精度和实时性,可用于湿法冶金工业生产过程。     

湿法炼锌铁钒除铁工艺管路结晶的机理探讨

通过对湿法炼锌过程所涉及的三元体系M_2SO_4-ZnSO_4-H_2O(M=K,Na,NH4)溶解度相图的比较研究,发现在上述三元体系中,在一般的冶炼工艺条件下,复盐(如(NH_4)_2SO_4·ZnSO_4·6H_2O(s)、Na_2SO_4·ZnSO_4·4H_2O(s)、K_2SO_4·ZnSO_4·6H_2O(s)远比单盐(如ZnSO_4·7H_2O(s)、Na_2SO_4(s)、K_2SO_4(s))要容易析出得多。这些复盐在溶液中的溶解度均随着温度的降低而降低,是管路结晶的主要诱因。溶解度较小的((NH_4)_2SO_4·ZnSO_4·6H_2O(s)生成是导致黄铵铁钒除铁过程管路易结晶堵塞的主因。     

Overlapped peaks resolution for linear sweep polarography using Gaussian-like distribution

A resolution method based on Gaussian-like distribution for overlapped linear sweep polarographic peaks was proposed to simultaneously detect the polymetallic components, such as Zn(II) and Co(II), coexisting in the leaching solution of zinc hydrometallurgy. A Gaussian-like distribution was constructed as the sub-model of overlapped peaks by analyzing the characteristics of linear sweep polarographic curve. Then, the abscissas of each peak and trough were pinpointed through multi-resolution wavelet decomposition, the curve and its derivative curves were fitted by using nonlinear weighted least squares (NWLS). Finally, overlapped peaks were resolved into independent sub-peaks based on fitted reconstruction parameters. The experimental results show that the relative error of half-wave potential pinpointed by multi-resolution wavelet decomposition is less than 1% and the accuracy of I_p fitted by NWLS is higher than 96%. The proposed resolution method is effective for overlapped linear sweep polarographic peaks of Zn(II) and Co(II).     

从锌冶炼净化渣中回收高品位铜精矿

锌冶炼净化渣先进行高温浸出,使锌、钴、镉等有价金属进入浸出液,而铜留在渣中,所得铜渣再经高酸浸出及水洗后得到铜精矿。结果表明,最佳高温浸出条件为:液固比(6⁷)∶1,始酸浓度100g/L、终点pH=3.0、807)∶1,始酸浓度100g/L、终点pH=3.0、80⁸5℃浸出8h;高酸洗涤最佳条件为:液固比(485℃浸出8h;高酸洗涤最佳条件为:液固比(4⁶)∶1,终点酸度50g/L,706)∶1,终点酸度50g/L,70⁸0℃浸出6080℃浸出60⁹0min。铜精矿含铜65%以上、含锌小于2%。     

从锌浸出渣中浮选银基础条件研究

研究了湿法炼锌常规浸出工艺下酸性浸出渣的浮选性质,提出并讨论了从锌常规浸出渣中浮选回收银的关键条件,认为锌常规浸出的酸浸矿浆直接作为原矿浆用于浮选回收银的工艺路线优势明显,银浮选回收可以达到较好的回收率、产率和精矿品位指标,并能在浮选中同时有效富集回收金。     

Binary Extraction in Hydrometallurgy

Abstract

Results obtained during technological application of binary extraction (extraction by salts of organic acids and organic bases) for recovery and separation of non-ferrous, rare, noble and associated metals are presented in the paper. The method of extraction of copper, especially from leaching solutions of oxidised ores, with the use of tertraoc-tylammonium dialkyldithiophosphate has been developed- The binary extractant is characterized by high separation coefficients of copper and iron, large capacity according to copper and high rate of its extraction and stripping by solutions of ammonia. The technology has also been tested in the sorption-extraction mode.

Possibilities of the use of binary extractants for the purification of sulphate solutions containing copper and iron, and also chloride solutions containing iron, have been discussed. The technological scheme developed for the purification of aluminium from iron in chloride solutions with the application of carboxylate of trialkylamine is characterized by a more concentrated strip solution obtained in comparison with the system based on trialkylamine.

The technology of the extraction of indium from Zn-containing sulphate solutions with the use of binary extraction by dialkylphosphate of trioctylamine has been developed and adopted at the Chetaybinsk zinc factory. The use of hydrochloric acid has been avoided in the stripping stage by the application of binary extractant. The technological scheme worked out for the extraction of cadmium from Zn-containing sulphate solutions with the use of carboxylate of trialkylamine allows one to achieve objectives of cadmium recovery in the form of chloride anion, cadmium concentration and conversion with the generation of cadmium sulphate solution suitable for cementation and also simultaneous purification of zinc sulphate solution from chloride ion with the production of concentrated solution of natrium chloride. Possible uses of binary extractants for the recovery of molybdenum as well as extraction and separation of platinum metals are also discussed.

In hydrometallurgy the extraction processes are most effectively applied to solve the following tasks:

?extraction (and usually simultaneous concentration) of valuable components in processing solutions with complex composition; - separation of elements with similar properties and their isolation into corresponding products;

?purification of aqueous technological solutions from elements - impurities; synthesis of inorganic compounds using, stripped solutions with definite element composition;

?purification of industrial sewage.

Obviously, an extractant is selected depending on the objectives. A search of extractants is a continuing process and a wide circle of specialists in the field of extraction chemistry and technology, organic synthesis, physical chemistry, and others take part inthis process. Recently processes of the so-called binary extraction have attracted re- searcher's attention considerably. A review of results obtained by us on the use of binary extraction for technological applications is given in the present paper.     

THE HYDROMETALLURGICAL EXTRACTION OF ZINC BY AMMONIUM CARBONATE: A REVIEW OF THE SCHNABEL PROCESS

The use of ammonium carbonate for the extraction of metals such as copper and nickel is well known. Less well known is the fact that ammonium carbonate extraction was used for the commercial recovery of zinc decades before its application to either copper or nickel. This article reviews the published data on the Schnabel Process (the hydrometallurgical extraction of zinc by ammonium carbonate) covering the period of 1880–2005.