title: Batch and continuous flow studies of adsorptive removal of Cr(VI) by adapted bacterial consortia immobilized in alginate beads.
abstract: The adsorptive removal of Cr(VI) by alginate beads containing Cr(VI)-adapted Acinetobacter junii, Escherichia coli and Bacillus subtilis in batch and continuous packed bed column reactors was investigated. Under optimized conditions (pH 3.0; contact time, 180 min; 30 °C; initial Cr(VI) concentration of 100 mg/L), 65.86 mg/g adsorption capacity was recorded in the batch study. When an adsorbent dosage of 1g/L, a flow rate of 5 mL/min, a bed height of 20 cm, an initial Cr(VI) concentration of 300 mg/L was employed, a capacity of 657 mg/g was noted for the continuous column assay. The batch sorption data followed the Langmuir isotherm and pseudo second order kinetics. Five sorption/desorption cycles yielded 100%, 99.63%, 95.31%, 80.7% and 74.22% regeneration, respectively. Cr(VI) adsorption studies using spiked ground water, freshwater and domestic wastewater in a packed bed reactor demonstrated Cr(VI) removals of 64.8%, 55.08%, 56.86% respectively. Cr(VI) sorption on immobilized bacteria was confirmed with Fourier-transform infrared and Energy dispersive X-ray spectroscopy.
authors.affiliation: Centre for Nanobiotechnology, VIT University, Vellore, Tamil Nadu, India.
authors.forename: Jastin
authors.initials: J
authors.lastname: Samuel
authors.forename: Mrudula
authors.initials: M
authors.lastname: Pulimi
authors.forename: Madona L
authors.initials: ML
authors.lastname: Paul
authors.forename: Arun
authors.initials: A
authors.lastname: Maurya
authors.forename: Natarajan
authors.initials: N
authors.lastname: Chandrasekaran
authors.forename: Amitava
authors.initials: A
authors.lastname: Mukherjee
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000327:Adsorption; D000464:Alginates / Q000737:chemistry*; D001422:Bacterial Adhesion / Q000502:physiology; D018407:Bacterial Physiological Phenomena; D061249:Batch Cell Culture Techniques / Q000379:methods*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D002857:Chromium / Q000302:isolation & purification / Q000378:metabolism*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D059013:Microbial Consortia / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D014874:Water Pollutants, Chemical; D002857:Chromium; D020723:Glucuronic Acid