Bioleaching method for the extraction of metals from coal fly ash using thiobacillus

摘要

A bioleaching process is utilized for the extraction of metals from coal fly ash (CFA). The CFA is suspended in an acidic sea water based culture medium and the suspension is incubated with a microorganism culture comprising at least one strain of Thiobacillus thiooxidans capable of growing and producing sulfuric acid in the sea water based acidic culture medium and thereby facilitating the extraction of metals from the CFA. The extracted metals are separated from the CFA raffinate and microorganism cells and are fractionated to provide metal-enriched fractions. A selected Thiobacillus thiooxidans strain is described which has been designated as Thiobacillus thiooxidans ZYR1, a sample of which has been deposited under No. 40453 at the National Collections of Industrial and Marine Bacteria Ltd. (NCIMB) at Aberdeen, Scotland. This selected strain is particularly suitable for the bioleaching of metals from coal fly ash.