Cyanide-Free Biocatalyzed Leaching of Gold and Silver Ore

这个小企业创新研究第一阶段项目将研究开发一种生物湿法冶金工艺的可行性，该工艺通过浸出的方式从生物氧化矿石中提取金和银，而不需要使用氰化物、硫脲、硫代硫酸盐或其他传统的浸出剂。金矿和银矿通常位于原始环境中，极易受到采矿和金属回收活动的污染。虽然生物技术已经开发出从难熔矿石中提取贵金属的方法，但氰化仍然是提取金银价值的首选方法。虽然研究的最终目标是开发堆浸过程，但在第一阶段将使用简化的工作模型来研究该过程。该工作模型将包括一个连续搅拌槽式反应器（CSTR），其中包含矿粒浆，以最大限度地减少传质限制。该项目包括使用数学模型推断最佳加工条件，设计工艺的实验工作模型，制作工作模型和开发实验技术，进行概念验证实验，以及分析这些实验的数据。建议对金银提取的基本技术进行重大改革，从源头上减少与采矿有关的污染。

This Small Business Innovation Research Phase I project will investigate the feasibility of developing a biohydrometallurgical process for extracting gold and silver from bio-oxidized ore by means of leaching that does not incorporate use of cyanide, thiourea, thiosulfate, or other conventional lixiviants. Gold and silver mines are often located in pristine environments that are highly susceptible to pollution by mining and metals recovery activities. While biotechnologies have been developed for freeing precious metals from refractory ores, cyanidation is still the process of choice for extracting gold and silver values. Whereas the ultimate goal of the research is to develop a heap leach process, a simplified working model will be used to study the process during Phase I. The working model will comprise a continuous stirred tank reactor (CSTR) containing a slurry of ore particles to minimize mass transfer limitations. The project includes using mathematical models to infer optimum processing conditions, designing an experimental working model of the process, fabricating the working model and developing experimental techniques, conducting proof-of-concept experiments, and analyzing the data from those experiments. A significant change in the basic technology of gold and silver extraction is proposed that will reduce mining-associated pollution at its source.