Arsenic(III) Removal at Low Concentrations by Biosorption using Phanerochaete chrysosporium Pellets

Abstract

As(III) removal from dilute aqueous solutions by biosorption onto pellets of the white rot fungus Phanerochaete chrysosporium was investigated. The As(III) uptake capacity was evaluated at low initial concentrations (0.2–1 mg/L) which revealed that the P. chrysosporium pellets were only slightly less efficient than the well studied adsorbent granular ferric hydroxide. Moreover, its performance was much more superior compared to anaerobic granular sludge, another cheaply available bacterial biosorbent. In the studied pH (5–9) and biomass concentration (0.25–1.5 g/L wet weight basis) ranges, no large differences in As(III) removal efficiency were observed. The influence of different ions, commonly present in groundwater, such as nitrate, fluoride, chloride, and Fe(III) on As(III) removal by the fungus was also examined by performing experiments as per the statistically valid two-level fractional factorial design of experiments. This showed a very good removal of only As(III) and Fe(III) (maximum 100%), the removal of the other ions in the mixture was very poor with the least well adsorbed being fluoride. A desorption efficiency exceeding 95% of the bound As(III) from the fungal biomass was achieved using sodium hydroxide (0.05–0.1 M) as desorbent.

Keywords:

• ANOVA
• As(III) removal
• biosorption
• interfering ions effect
• Phanerochaete chrysosporium pellets
• statistical design of experiments

ACKNOWLEDGEMENTS

The authors thankfully acknowledge financial support from the Department of Science and Technology, India, under the BOYSCAST fellowship (SR/BY/L-19/10) and a postdoctoral fellowship from the Conselleria d'Educacio of Generalitat Valenciana (Spain).

Notes

^a q_e, solid-phase equilibrium As(III) concentration (mg/g); C _e , liquid-phase metal ion concentration (mg/L); q _max , maximum uptake capacity in Langmuir model (mg/g); b, constant in Langmuir model (L/mg); K _F , Freundlich equilibrium constant (L/mg); n, dimensionless parameter in Freundlich model; K _R and a _R , Redlich-Peterson model constants (L/g and L/mg, respectively); β, dimensionless exponent in Redlich-Peterson model; q′ _max , maximum sorption capacity in SIPS model (mg/g), b, a constant in SIPS model (L/mg); n′, dimensionless parameter in SIPS model; q _B , sorption capacity in BET model (mg/g); K _S and K _L , constants in BET model (L/mg).