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.
作者
马晋芳
李乾
孙静
杨雨
李广悦
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)
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)。
关键词
铁硫质量比
铁硫氧化细菌
生物浸出
浸铀行为
Fe/S quality ratio
iron/sulfur oxidizing bacterial consortium
bioleaching
uranium bioleaching behaviors
