Jump to Main Content
Hexavalent chromium removal by viable, granular anaerobic biomass
- Massara, Hafez, Mulligan, Catherine N., Hadjinicolaou, John
- Bioresource technology 2008 v.99 no.18 pp. 8637-8642
- industrial effluents, wastewater, chromium, toxicity, anaerobes, sorption, bioremediation, biogas, chemical oxygen demand, methanogens, bacteria, inhibitory concentration 50, viability, simulation models, uptake mechanisms, waste treatment
- Hexavalent chromium in industrial wastewater is a major concern due to its extreme toxicity. This study investigates the removal of Cr(VI) using viable anaerobic granular biomass as a biosorbent. The effect of Cr(VI) concentration on biogas content and COD removal using batch studies indicated that the phase II (methanogenic-rich) culture was more sensitive than the phase I (acidogenic-rich) culture. Toxicity indices for both cultures using COD removal were developed based on linear-log interpolation. The median inhibition Cr(VI) concentration (IC₅₀), for phase II cultures was found to be 263mg/L, while that for phase I cultures was 309mg/L. A sorption study was conducted on viable and non-viable (dried) phase I-rich biomass: both followed the Langmuir model. In addition, the biosorption capacity for metabolically inhibited biomass was 25% less indicating some level of cellular uptake associated with Cr(VI) removal. This study demonstrated the potential for a two-phase anaerobic treatment system for a Cr(VI)-contaminated effluent.