Fe/S质量比对铁硫氧化细菌菌群浸铀行为的影响及其作用机制  

Effects and Mechanism of Fe/S Quality Ratio on Uranium Leaching Behaviors of Rron/Sulfur Oxidizing Bacterial Consortium

作　　者：马晋芳 李乾 孙静[1,2] 杨雨 李广悦[1,2] 史文革 MA Jinfang;LI Qian;SUN Jing;YANG Yu;LI Guangyue;SHI Wenge(School of Resource Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China;Key Discipline Laboratory of National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, Hunan 421001, China)

机构地区：[1]南华大学资源环境与安全工程学院,湖南衡阳421001 [2]南华大学铀矿冶生物技术国防重点学科实验室,湖南衡阳421001

出　　处：《南华大学学报（自然科学版）》2021年第4期22-28,共7页Journal of University of South China：Science and Technology

基　　金：国家自然科学基金项目(51804165);湖南省自然科学基金项目(2018JJ3441);南华大学研究生科研创新项目(203YXC005)。

摘　　要：为了探明能源基质中Fe/S质量比对铁硫氧化细菌菌群浸铀行为的影响及其作用机制,研究了不同Fe/S质量比作用下铁硫氧化细菌菌群浸铀过程中的浸出液变化、钝化层表面特性及微生物群落动态三方面的差异。结果表明:当Fe/S质量比为5∶0.5、5∶1和5∶5时,铀浸出率均达到90%以上,而在Fe/S质量比为5∶0和5∶10,铀浸出率降低,分别为45.92%和36.96%;添加一定硫粉后(Fe/S质量比为5∶0.5、5∶1和5∶5),可降低体系酸度,降低矿物表面钝化物的产生,增加钝化物的孔隙度,但是添加量过高致使矿石表面形成多硫聚合物而降低A.ferrooxidans的活性,不利于铀的浸出。当Fe/S质量比为5∶0.5、5∶1和5∶5时,浸矿前期A.thiooxidans A01浓度较高,有利于降低体系的pH,创造良好的浸铀条件;在浸矿后期,A.ferrooxidans ATCC 23270浓度逐渐升高,在浸铀过程中发挥着主导作用。In order to explore the impacts of Fe/S quality ratio on the behaviors of uranium bioleaching by an iron/sulfur oxidizing bacterial consortium,the differences of leachate chemical parameters,bacterial community dynamics and surface characteristics of mineral residues upon the different Fe/S quality ratio were analyzed.The results showed that the uranium recovery was achieved to over 90%under the Fe/S quality ratio of 5∶0.5,5∶1 and 5∶5,while the uranium recovery was decreased under the Fe/S quality ratio of 5∶0 and 5∶10,45.92%and 36.96%respectively.Addition of appropriate sulfur(Fe/S as 5∶0.5,5∶1 and 5∶5)would intensify the acidity,and also,it would inhibit the formation of the passivation substance on the mineral surface and increase the porosity.But excessive sulfur(Fe/S as 5∶10)would probably decrease the activity of A.ferrooxidans owing to the formation of polysulfide,which would lead the decrease of the uranium recovery.At the Fe/S quality ratio of 5∶0.5,5∶1 and 5∶5,the A.thiooxidans A01 concentration reached a peak at the early phase,which was beneficial to decrease the pH and to provide a preferable surroundings for bactebial growth.The A.ferrooxidans ATCC 23270 concentration gradually increased subsequently,which exerted an dominant role at the middle and late phase in the uranium bioleaching process.

关 键 词：铁硫质量比 铁硫氧化细菌 生物浸出 浸铀行为 

分 类 号：TL212.12[核科学技术—核燃料循环与材料]