Enhanced effect of biochar on leaching vanadium and copper from stone coal tailings by Thiobacillus ferrooxidans

Abstract

Among the many extraction technologies for recovering metal resources from tailings, bioleaching technology is gradually showing its momentum. In our research, the enhanced effect of biochar on the bioleaching of stone coal tailings by Thiobacillus ferrooxidans (T. ferrooxidans) has been explored. In the static bioleaching experiment for 10 days, the leaching rate of vanadium (V) and copper (Cu) increased by 26.8% and 21.0% respectively after adding 5 g/L biochar. The dynamic bioleaching experiment further verified that under the promotion of biochar, the 44 day cumulative leaching rate of V and Cu increased by 15.3% and 14.5%, respectively. The promoting effect of biochar on T. ferrooxidans was mainly reflected in two aspects. The unique porous structure of biochar created a microenvironment for free microorganisms for inhabitation, while storing abundant nutrients. Biochar can also act as an excellent electronic medium to promote electron transfer, improving the oxidation ability of T. ferrooxidans on Fe 2+ . Furthermore, the presence of biochar may effectively inhibit the formation of jarosite precipitation on tailings in bioleaching, thereby improving the dissolution of tailings and the release of metal elements. This study demonstrates that biochar-enhanced bioleaching may be an efficient and environmentally friendly method for recovering metal resources from tailings.

Application Prospect of Anaerobic Reduction Pathways in Acidithiobacillus ferrooxidans for Mine Tailings Disposal: A Review

“…Yang, Chen [78] found that with the addition of Fe 3+ , the rate and efficiency of jarosite bio-dissolution can be significantly accelerated and improved. Dong, Chong [81] explored the enhanced effect of biochar on the bioleaching of stone coal tailings by At. ferrooxidans.…”

Electrochemical corrosion behavior and mechanism of iron-oxidizing bacteria Thiobacillus ferrooxidans from acid mine drainage on Q235 carbon steel

“…Inspection results of underground water from coal mines in several places had shown that Thiobacillus ferrooxidans was one of the most pervasive bacteria in the mining area. 2,3 These bacteria are commonly used in bioleaching, 4,5 treatment of acid mineral wastewater, 6,7 and treatment of used circuit boards. 8,9 There are other bacteria such as Thiobacillus thiooxidans and Aspergillus niger , which could also recover metals through bioleaching.…”

Heterotrophic Bioleaching of Vanadium from Low-Grade Stone Coal by Aerobic Microbial Consortium

“…Bioleaching is introduced as an environment-friendly method requiring less complexity and cost in operation [ 19 , 20 ], and can be an alternative to chemical extraction. In fact, vanadium has been recovered from industrial wastes such as stone coal [ 21 ], spent refinery catalysts [ 22 ], vanadium-bearing shale and slag fly ash through bioleaching process [ 23 , 24 ]. Chemolithotrophic bacteria, such as the Acidithiobacillus species, are well known for their use in metal bioleaching (e.g., copper, gold, and uranium) from ore deposits and mine tailings [ 25 ].…”