| Autor: |
Zhang S; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Chen X; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Teng S; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Shi G; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Cheng J; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Zhang N; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn., Shao Q; College of Environmental and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100080, P. R. China., Cui Y; Tangshan Research Institute, Beijing Institute of Technology, Tangshan 063000, P. R. China., Wang J; Tangshan Research Institute, Beijing Institute of Technology, Tangshan 063000, P. R. China.; College of Environmental and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100080, P. R. China., Xin B; School of Materials Sciences and Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China. xinbaoping@bit.edu.cn.; Tangshan Research Institute, Beijing Institute of Technology, Tangshan 063000, P. R. China. |
| Abstrakt: |
The extraction and recovery of valuable metals from various spent catalysts via bioleaching represents a green, low-carbon and eco-friendly process. However, the pulp density of spent catalysts is usually 1.0% or lower owing to their toxicity, denoting low process capacity and poor practical potential. In this study, an intensified bioleaching strategy was used for the first time to promote the release efficiencies of both Co and Mo from a spent Co-Mo catalyst at a high pulp density of 10% by supplementing extracellular polymeric substances (EPSs). The results showed that the addition of 0.6 g L -1 EPSs harvested a maximum release of 73.6% for Co and 72.5% for Mo after 9 days of contact, with an evident elevation of 22.6% for Co and 24.4% for Mo, in contrast to no addition, respectively. The added EPS not only promoted the growth of plankton cells to produce more active molecules but also boosted the adhesion of leaching cells to the spent catalyst to form stable aggregates. Moreover, the resulting aggregates allowed for the gathering and confinement of the active small molecules, including Fe 3+ and Fe 2+ , inside the micro-areas between the spent catalysts and the cells for quick electronic transfer as an interface oxidation/reduction reaction to free both Co and Mo from the spent catalyst. |
