Jump to Main Content
Enhancement in Iron Oxidation and Multi-metal Extraction from Waste Television Printed Circuit Boards by Iron Oxidizing Leptospirillum feriphillum Isolated from Coal Sample
- Asha B. Sodha, Sufiya A. Qureshi, Bhumika R. Khatri, Devayani R. Tipre, Shailesh R. Dave
- Waste and biomass valorization 2019 v.10 no.3 pp. 671-680
- Leptospirillum, coal, copper, iron, leaching, nickel, oxidants, oxidation, pH, particle size, pulp, television, wastes, zinc
- Purpose of this study was to analyse the ability of isolated Leptospirillum to extract the metals from television printed circuit boards (TV-PCBs). Activation of iron oxidizer enriched from coal sample resulted in 8.5-fold enhancement in iron oxidation rate. The television printed circuit board (TV-PCBs) adapted culture showed 1.2-, 1.3- and 1.6-fold higher Cu, Zn and Ni leaching, respectively, from 10 g/L TV-PCBs waste pulp density compared to unadapted culture. It also showed 24-h reduction in leaching time. The two-step process showed 1.3-fold higher metal extractions compared to one-step process with both adapted and unadapted culture. Additionally, there was a 1.3-fold reduction in reaction time in the two-step leaching process as compared to the one-step process. The effect of change in leaching process parameters such as pH, Fe (III) concentrations, and particle size were investigated. The maximum metal leaching occurred at a pH of 2.0, Fe (III) concentration of 8.2 g/L, and at particle size less than 0.044 mm. Under the above-stated optimum conditions, all the three metal extractions namely Cu, Zn and Ni were greater than 95%.