Water Science and Technology (Apr 2023)
Assessment of the induced effect of selected iron hydroxysulfates biosynthesized using Acidithiobacillus ferrooxidans for biomineralization of acid mine drainage
Abstract
Soluble iron and sulfate in acid mine drainage (AMD) can be greatly removed through the formation of minerals facilitated by seed crystals. However, the difference in the effects of jarosite and schwertmannite as endogenous seed crystals to induce AMD mineralization remains unclear. This paper intends to study the effect of Fe2+ oxidation and Fe3+ mineralization in the biosynthesis of minerals using different addition amounts and methods of jarosite or schwertmannite. The results showed that the addition amount and method of different seed crystals had no effect on the Fe2+ bio-oxidation but would change the Fe3+ mineralization efficiency. With the same amount of seed crystals added, jarosite exhibited a higher capacity to promote Fe3+ mineralization than schwertmannite. Adding seed crystals before the initiation of Fe2+ oxidation (0 h) could significantly promote Fe3+ mineralization efficiency. With the increase of seed crystals, jarosite could not only shorten the time required for mineral synthesis but also improve the final mineral yield, whereas schwertmannite could only shorten the time required for mineral synthesis. When Fe2+ was completely oxidized to Fe3+ (48 h), the supplementary of jarosite could still effectively improve Fe3+ mineralization efficiency, but the addition of schwertmannite no longer affected the final mineralization degree. HIGHLIGHTS The addition of jarosite and schwertmannite had no significant effect on the bio-oxidation of Fe2+ by A. ferrooxidans but would change the mineralization efficiency of Fe3+.; The effect of jarosite addition on the mineralization of Fe3+ was much greater than that of schwertmannite addition.; Adding seed crystals before the initiation of Fe2+ oxidation could significantly promote Fe3+ mineralization efficiency.;
Keywords
