title: Biosorption of As (III) by non-living biomass of an arsenic-hypertolerant Bacillus cereus strain SZ2 isolated from a gold mining environment: equilibrium and kinetic study.
abstract: The ability of non-living biomass of an arsenic-hypertolerant Bacillus cereus strain SZ2 isolated from a gold mining environment to adsorb As (III) from aqueous solution in batch experiments was investigated as a function of contact time, initial As (III) concentration, pH, temperature and biomass dosage. Langmuir model fitted the equilibrium data better in comparison to Freundlich isotherm. The maximum biosorption capacity of the sorbent, as obtained from the Langmuir isotherm, was 153.41 mg/g. The sorption kinetic of As (III) biosorption followed well the pseudo-second-order rate equation. The Fourier transform infrared spectroscopy analysis indicated the involvement of hydroxyl, amide and amine groups in As (III) biosorption process. Field emission scanning electron microscopy-energy dispersive X-ray analysis of the non-living B. cereus SZ2 biomass demonstrated distinct cell morphological changes with significant amounts of As adsorbed onto the cells compared to non-treated cells. Desorption of 94 % As (III) was achieved at acidic pH 1 showing the capability of non-living biomass B. cereus SZ2 as potential biosorbent in removal of As (III) from arsenic-contaminated mining effluent.
authors.affiliation: Department of Biosciences and Health Sciences, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.
authors.forename: Zaratulnur
authors.initials: Z
authors.lastname: Mohd Bahari
authors.forename: Wahid
authors.initials: W
authors.lastname: Ali Hamood Altowayti
authors.forename: Zaharah
authors.initials: Z
authors.lastname: Ibrahim
authors.forename: Jafariah
authors.initials: J
authors.lastname: Jaafar
authors.forename: Shafinaz
authors.initials: S
authors.lastname: Shahir
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000633:toxicity*; D001409:Bacillus cereus / Q000187:drug effects / Q000254:growth & development*; D001673:Biodegradation, Environmental; D018533:Biomass; D006046:Gold; D006801:Humans; D007700:Kinetics; D013696:Temperature; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D014874:Water Pollutants, Chemical; D006046:Gold; D001151:Arsenic