Feasibility of Using Microalgal Biomass Cultured in Domestic Wastewater for the Removal of Chromium Pollutants

• Published in: Water environment research Vol. 80; no. 7; pp. 647 - 653
• Main Authors: Han, Xu, Wong, Yuk Shan, Wong, Ming Hung, Tam, Nora Fung Yee
• Format: Journal Article
• Language: English
• Published: Alexandria, VA Water Environment Federation 01.07.2008; Blackwell Publishing Ltd
• Subjects: Applied sciences; Biochemistry; Biological and medical sciences; Biomass; Biomass production; biosorption; Biotechnology; Cells; Chemical composition; Chemical oxygen demand; Chemical precipitation; Chlorella - growth & development; Chlorella - metabolism; Chlorella miniata; Chromium; Chromium - isolation & purification; Chromium - metabolism; domestic wastewater; Exact sciences and technology; Fourier transform infrared spectrometer; Fourier transforms; Fundamental and applied biological sciences. Psychology; General purification processes; Ion exchange; Kinetics; Methods. Procedures. Technologies; microalga; Microalgae; Nitrogen; Nutrient removal; Others; Pollution; Sulfuric acid; Various methods and equipments; Wastewater; Wastewater treatment; Wastewaters; Water Pollutants, Chemical - isolation & purification; Water Pollutants, Chemical - metabolism; Water pollution; Water Purification - methods; Water treatment; Water treatment and pollution; Domestic waste water; Pollutant; Pollution; Biosorption; Chromium III; Biomass; Contamination
• ISSN: 1061-4303; 1554-7531
• DOI: 10.1002/j.1554-7531.2008.tb00351.x

The feasibility of obtaining and using the biomass of a microalga, Chlorella miniata, from domestic wastewater (DW) cultures for the removal of and chromium(III) [Cr(III)] and chrominum (VI) [Cr(VI)] was compared with that from commercial Bristol medium (BM). Results showed that Chlorella miniata cultured in DW under 16-8 hours light-dark cycle [DW(16-8)] had similar growth to that in BM BM(16-8)], but these two biomass had different biochemical compositions, and the former one had lower carbohydrate and higher protein content. When cultured in domestic wastewater, a higher biomass was obtained under continuous illumination [DW(24-0)], and the cells had higher carbohydrate and lower protein concentrations than that of DW(16-8). The spectra of the Fourier transform infrared spectrometer revealed that the functional groups on the surface of the three kinds of biomass—DW(16-8), DW(24-0), and BM(16-8)—were comparable, except an additional peak at 1731 cm⁻ⁱ was found in the biomass cultured in domestic wastewater, which was probably the result of bacterial contamination. Although biochemical differences were found among the three kinds of microalgal biomass, similar biosorption performances to chromium pollutants were recorded, with approximately 75% Cr(III) and 100% Cr(VI) removed át equilibrium in and Cr(VI) and Cr(VI) experiments, respectively, when dead biomass was used as a biosorbent. Therefore, it is possible to culture Chlorella miniata in domestic wastewater and use the biomass for the removal of chromium pollutants.