Ni2+ Removal and Recovery from Electroplating Effluent by Pseudomonas putida 5-x Cell Biomass

• Published in: Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering Toxic/hazardous substances & environmental engineering, 2003-04, Vol.38 (3), p.521-531
• Main Authors: Wang, L., Chua, H., Wong, P. K., Lo, W. H., Yu, P. H. F.
• Format: Article
• Language: English
• Subjects: Adsorption; Biodegradation, Environmental; Biomass; Biosorption; Cell pretreatment; Desorption; Effluents; Electroplating; Growth phase; Isotherms; Nickel - chemistry; Nickel - isolation & purification; Pseudomonas putida; Pseudomonas putida - physiology; Recovery; Transmission electron microscopy; Waste Disposal, Fluid; Waste water; Water Purification - methods
• ISSN: 1093-4529; 1532-4117
• DOI: 10.1081/ESE-120016912

Ni 2+ and Cu 2+ are the major heavy metal ions in electroplating wastewater of Hong Kong. In the present study, Pseudomonas putida 5-x cell biomass was used to remove Ni 2+ from electroplating effluent. Ni 2+ adsorption capacity of P. putida 5-x cell biomass cultured in sulphate-limiting medium was found to be minimum in early logarithmic growth phase, and maximum of 28.1 mg g −1 in late stationary growth phase. Pretreated cells by 0.1 mol L −1 HCl could greatly enhance the Ni 2+ adsorption capacity of cell biomass from 28.1 to 36.7 mg g −1 and had no significant effect on biomass loss. The adsorption process of P. putida 5-x fresh cells and pretreated cell all could be expressed with Freundlich isotherm. TEM analyses indicated that acidic pretreatment degraded the superficial layer-capsule outside of the fresh cell to improve the adsorption capacity of cell to Ni 2+ . The Ni 2+ bound by P. putida 5-x cell biomass could be efficiently recovered using 0.1 mol L −1 HCl, and the cell biomass could be reused at least five cycles for Ni 2+ removal and recovery with 93% above removal efficiency and 98% above recovery rate. Owing to the Cu 2+ presented in electroplating wastewater inhibiting Ni 2+ adsorption process by P. putida 5-x cell biomass, two-stage biosorption processes should be designed to remove and recover Cu 2+ and Ni 2+ sequentially from electroplating effluent.