Prospective application of Aspergillus species immobilized in sodium montmorillonite to remove toxic hexavalent chromium from wastewater

Abstract

Aspergillus BRVR immobilized in sodium montmorillonite for the effective removal of Cr(vi) from waste water.

Metallophilic fungi research: an alternative for its use in the bioremediation of hexavalent chromium

“…These results are similar to Mungasavalli et al (2007), Pang et al (2011), Kavita and Keharia (2012), Abubacker and Kirthiga (2013) and Sathvika et al (2015), where the optimal pH for the Cr(VI) biosorption was between 1 and 3. The biosorption process depends largely on the pH of the aqueous solution, because the surface charge of the biomass cell wall is modified by the pH variations.…”

Adsorption of chromium supported with various column modelling studies through the synergistic influence of Aspergillus and cellulose

“…At pH 2.0 and at a working Cr(VI) concentration of 5 mg L -1 there was 100% Cr(VI) removal efficiency and the percentage adsorption decreased with increasing pH. As shown in Fig.3A, HCrO4 -exists at the acidic pH (2.0) and at this acidic pH the functional groups present in the fungal cell wall (NH2, OH and COOH) as well as cellulose gets protonated resulting in electrostatic interactions [26] ( Fig.4) . The epichlorohydrin used for the crosslinking of cellulose strengthens the biopolymer and the fungus when immobilized in the crosslinked cellulose has increased the probability of entering the voids of cellulose layer.…”

“…The filamentous fungi was isolated from bread mould and the strain (Aspergillus BRVR) was confirmed through DNA isolation, Polymerase Chain Reaction and sequencing with a Gen bank accession number KT699195 as reported by our group previously [26]. The fungi was maintained on a Sabaroud Dextrose medium and the biomass was dried overnight at 70 o C [36], ground to a fine powder and used in the biosorption studies.…”

“…The percentage removal of chromium increased with the decreasing pH, owing to the effective interaction of the functional groups in the biosorbent with the Cr(VI) species existing in the form of HCrO4 -and Cr2O7 2- [26]. Cr(VI) at varying pH, exists as tetraoxohydrochromate (HCrO4 -), chromate (CrO4 2-) and dichromate (Cr2O7 2-) ions.…”

“…Sujoy et al [24] reported the interaction of chromium with Aspergillus versicolor using Atomic force microscopy (AFM) and Transmission electron microscopies (TEM) and the XPS, FTIR studies revealed that bound Cr was in the form Cr(III) involving adsorption coupled reduction. Mungasavalli et al [25] reported that the pre-treated Aspergillus niger could adsorb chromium effectively with 15.2 mg g -1 Langmuir adsorption capacity, Aspergillus sp immobilized in sodium montmorillonite is reported to have good potential for Cr(VI) removal with an adsorption capacity of 45.67 mg g -1 [26]. Microwave assisted preparation of biosorbent such as yeast immobilized in cellulose can efficiently remove Cr(VI) with an adsorption capacity of 23.61 mg g -1 [27].…”