Q-208. Biosorption of Ru and Ir by a Bacterial Biomass in Industrial Wastewater Produced from an Acetic Acid Manufacturing Plant
The interactions of microorganisms and metals in aqueous media have been the focus of growing number of scientific studies in recent years. The passive binding of metals by microbes is commonly termed biosorption. This study shows the use of bacterial biomass as a biosorbent of Ru and Ir in industrial wastewater produced from an acetic acid manufacturing plant and suggests the method for recovering the valuable metals in industrial wastewater. Corynebacterium glutamicum chosen in this study is widely used in amino acid fermentation industry, and a large amount of the biomass is produced as byproduct. The fermentation waste (C. glutamicum) were obtained in a dried powder form from a mono sodium glutamate fermentation industry (Daesang, Gunsan, Korea). The biomass was dried by using spray-drying process for 24h, and the dried biomass was used as a sorbent. The sorption performance (in particular the sorption capacity and kinetics) was investigated in detail and the sequencial batch experiments were carried out for considering efficient application method. The uptake capacities of Ru and Ir were 23.6 mg/g and 1.9 mg/g, respectively, while commercial ion exchange resin (Amberjet 4200, Merck) showed relatively low sorption capacity (less than 4 mg/g and 0.2 mg/g for the Ru and Ir, respectively). Kinetic experiments showed 1 h is enough time for equilibrium reached. Sequencial batch experiments showed that more than 90% removal was maintained up to 5 times cycles, and the removal efficiency slowly decreased as the number of batch cycle increased. In this study, we reported for the first time that the biosorption by bacterial biomass produced as byproduct can be used as a method for recovering the valuable metals in industrial wastewater. Sequencial batch can be suggested for an efficient application method rather than column operation.