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Hexavalent chromium bioremoval through adaptation and consortia development from sukinda chromite mine isolates / Jastin Samuel in Industrial & engineering chemistry research, Vol. 51 N° 9 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3740-3749 Titre : Hexavalent chromium bioremoval through adaptation and consortia development from sukinda chromite mine isolates Type de document : texte imprimé Auteurs : Jastin Samuel, Auteur ; Madona L Paul, Auteur ; Mrudula Pulimi, Auteur Année de publication : 2012 Article en page(s) : pp. 3740-3749 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Chromite  mine  isolates Résumé : Indigenous isolates from the waters of chromite mining sites at Sukinda Valley, Orissa, India, showed a considerable enhancement in Cr (VI) bioreduction rate through adaptation and consortia development. On the basis of 16S-rRNA sequencing, these isolates were identified as Bacillus subtilis VTTSUKMW1, Acinetobacter junii VITSUKMW2, and Escherichia coli VITSUKMW3. The native isolates showed a high tolerance at 500-1000 mg L―1 of Cr (VI). An increase in the reduction rate from 0.199-0.477 mg L―1 h―1 to 0.5-1.16 mg L―1 h―1 at 5-20 mg L―1 of initial Cr (VI) concentration was achieved by the adapted isolates. An increase in the growth rate and Cr (VI) reduction rate [0.86―2.6813 mg L―1 h―1 at 5―100 mg L―1 of initial Cr (VI) concentration] was observed in the ternary consortium of adapted isolates. The FT-IR spectra revealed the active participation of the bacterial surface groups in the reduction. The development of sequential processes (native → adapted → consortia) employing Cr (VI) tolerant isolates, proves to be a potential bioremediation strategy for specific chromite mine sites. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201796s [article] Hexavalent chromium bioremoval through adaptation and consortia development from sukinda chromite mine isolates [texte imprimé] / Jastin Samuel, Auteur ; Madona L Paul, Auteur ; Mrudula Pulimi, Auteur . - 2012 . - pp. 3740-3749. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 9 (Mars 2012) . - pp. 3740-3749 Mots-clés : Chromite  mine  isolates Résumé : Indigenous isolates from the waters of chromite mining sites at Sukinda Valley, Orissa, India, showed a considerable enhancement in Cr (VI) bioreduction rate through adaptation and consortia development. On the basis of 16S-rRNA sequencing, these isolates were identified as Bacillus subtilis VTTSUKMW1, Acinetobacter junii VITSUKMW2, and Escherichia coli VITSUKMW3. The native isolates showed a high tolerance at 500-1000 mg L―1 of Cr (VI). An increase in the reduction rate from 0.199-0.477 mg L―1 h―1 to 0.5-1.16 mg L―1 h―1 at 5-20 mg L―1 of initial Cr (VI) concentration was achieved by the adapted isolates. An increase in the growth rate and Cr (VI) reduction rate [0.86―2.6813 mg L―1 h―1 at 5―100 mg L―1 of initial Cr (VI) concentration] was observed in the ternary consortium of adapted isolates. The FT-IR spectra revealed the active participation of the bacterial surface groups in the reduction. The development of sequential processes (native → adapted → consortia) employing Cr (VI) tolerant isolates, proves to be a potential bioremediation strategy for specific chromite mine sites. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201796s

Studies on Cr(VI) removal from aqueous solutions by nanoalumina / Madona Lien Paul in Industrial & engineering chemistry research, Vol. 51 N° 46 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 15242-15250 Titre : Studies on Cr(VI) removal from aqueous solutions by nanoalumina Type de document : texte imprimé Auteurs : Madona Lien Paul, Auteur ; Jastin Samuel, Auteur ; Sushree Bedatrayee Das, Auteur Année de publication : 2013 Article en page(s) : pp. 15242-15250 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Aqueous  solution Résumé : The current study deals with Cr(VI) removal using unmodified alumina nanoparticles of two different sizes (NA1: mean hydrodynamic diameter = 75.3 ± 2.8 nm; NA2: mean hydrodynamic diameter = 229.8 ± 3.3 nm). The equilibrium adsorption capacities, 73.2 and 59.4 mg of Cr(VI)/g of adsorbent, were noted for NA1 and NA2, respectively, under optimized conditions (pH 7.0, temperature = 27 °C, initial Cr(VI) concentration = 20 mg L―1, adsorbent dosage = O.lg L―1) but different contact times (120 min for NA1, 180 min for NA2). For both sorbents, the equilibrium adsorption data fitted well with the Langmuir isotherm model. The adsorbent NA1 followed a pseudo-second-order kinetics, whereas NA2 followed pseudo-first-order kinetics. Surface characterization studies (zeta potential measurement, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) spectroscopy) substantiated oxyanionic binding on the sorbent surface. The EPR and XRD spectroscopy confirmed the existence of reduced Cr(III) on the adsorbent surface. The applicability of the sorbent in Cr(VI)-contaminated water was studied. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26679644 [article] Studies on Cr(VI) removal from aqueous solutions by nanoalumina [texte imprimé] / Madona Lien Paul, Auteur ; Jastin Samuel, Auteur ; Sushree Bedatrayee Das, Auteur . - 2013 . - pp. 15242-15250. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 15242-15250 Mots-clés : Aqueous  solution Résumé : The current study deals with Cr(VI) removal using unmodified alumina nanoparticles of two different sizes (NA1: mean hydrodynamic diameter = 75.3 ± 2.8 nm; NA2: mean hydrodynamic diameter = 229.8 ± 3.3 nm). The equilibrium adsorption capacities, 73.2 and 59.4 mg of Cr(VI)/g of adsorbent, were noted for NA1 and NA2, respectively, under optimized conditions (pH 7.0, temperature = 27 °C, initial Cr(VI) concentration = 20 mg L―1, adsorbent dosage = O.lg L―1) but different contact times (120 min for NA1, 180 min for NA2). For both sorbents, the equilibrium adsorption data fitted well with the Langmuir isotherm model. The adsorbent NA1 followed a pseudo-second-order kinetics, whereas NA2 followed pseudo-first-order kinetics. Surface characterization studies (zeta potential measurement, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) spectroscopy) substantiated oxyanionic binding on the sorbent surface. The EPR and XRD spectroscopy confirmed the existence of reduced Cr(III) on the adsorbent surface. The applicability of the sorbent in Cr(VI)-contaminated water was studied. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26679644