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Total recovery of gold, palladium, and platinum using lignophenol derivative / Durga Parajuli in Minerals engineering, Vol. 22 N° 13 (Octobre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 13 (Octobre 2009) . - pp. 1173–1178 Titre : Total recovery of gold, palladium, and platinum using lignophenol derivative Type de document : texte imprimé Auteurs : Durga Parajuli, Auteur ; Kanjana Khunathai, Auteur ; Chaitanya Raj Adhikari, Auteur Année de publication : 2009 Article en page(s) : pp. 1173–1178 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : DMA-CLP  Precious  metals  Ion  exchange  Aqua  regia  sample Résumé : A tertiary amine type adsorption gel was prepared by the immobilization of dimethylamine onto crosslinked lignophenol (CLP) matrix. This novel product was studied for its adsorption behavior for Au(III), Pd(II), Pt(IV), Cu(II), Zn(II), Ni(II), and Fe(III) in 0.5–6 M hydrochloric acid medium. From our previous study, crosslinked lignophenol (CLP) is known to hold solo selectivity for Au(III). After modification to dimethylamine type adsorbent (DMA-CLP), an extended selectivity of Au(III), Pd(II), and Pt(IV) was observed. The maximum loading capacity for these three metal ions was evaluated by isotherm study. For Au(III) an impressive value of 7.2 mol/kg of DMA-CLP was observed. The feasibility of recovery of precious metals from a mixture containing several other metal ions was studied in batch mode by using both model solution and actual industrial solution obtained after aqua regia leaching of metal components in obsolate e-devices. In addition, a number of adsorption–elution cycles were produced so as to know the feasibility of multiple uses. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001484 [article] Total recovery of gold, palladium, and platinum using lignophenol derivative [texte imprimé] / Durga Parajuli, Auteur ; Kanjana Khunathai, Auteur ; Chaitanya Raj Adhikari, Auteur . - 2009 . - pp. 1173–1178. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 13 (Octobre 2009) . - pp. 1173–1178 Mots-clés : DMA-CLP  Precious  metals  Ion  exchange  Aqua  regia  sample Résumé : A tertiary amine type adsorption gel was prepared by the immobilization of dimethylamine onto crosslinked lignophenol (CLP) matrix. This novel product was studied for its adsorption behavior for Au(III), Pd(II), Pt(IV), Cu(II), Zn(II), Ni(II), and Fe(III) in 0.5–6 M hydrochloric acid medium. From our previous study, crosslinked lignophenol (CLP) is known to hold solo selectivity for Au(III). After modification to dimethylamine type adsorbent (DMA-CLP), an extended selectivity of Au(III), Pd(II), and Pt(IV) was observed. The maximum loading capacity for these three metal ions was evaluated by isotherm study. For Au(III) an impressive value of 7.2 mol/kg of DMA-CLP was observed. The feasibility of recovery of precious metals from a mixture containing several other metal ions was studied in batch mode by using both model solution and actual industrial solution obtained after aqua regia leaching of metal components in obsolate e-devices. In addition, a number of adsorption–elution cycles were produced so as to know the feasibility of multiple uses. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001484

Trimethylamine-modified lignophenol for the recovery of precious metals / Durga Parajuli in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10163–10168 Titre : Trimethylamine-modified lignophenol for the recovery of precious metals Type de document : texte imprimé Auteurs : Durga Parajuli, Auteur ; Koichi Hirota, Auteur ; Katsutoshi Inoue, Auteur Année de publication : 2010 Article en page(s) : pp. 10163–10168 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Trimethylamine-Modified--Lignophenol--Recovery--Precious--Metals Résumé : A quaternary amine-type sorbent has been prepared by the immobilization of trimethylamine group onto the cross-linked lignophenol matrix. The sorption behavior for a number of metal ions was studied in hydrochloric acid medium. From the batch test of individual metal ion as well as the mixture solution containing equal molar concentration of various metal ions, the sorbent was found to hold selectivity for Au(III), Pd(II), and Pt(IV) ions only with negligible sorption for other metal ions like Cu(II), Co(II), Fe(III), Ni(II), and Zn(II). The sorption kinetics was studied at 30, 50, and 65 °C and elucidated the order of sorption of Au(III), Pd(II), and Pt(IV) and from the values of rate constants at different temperatures, the energy of activation has been evaluated. The sorption isotherm study revealed the Langmuir type sorption and from the Langmuir charts the maximum loading capacity of Au(III), Pd(II), and Pt(IV) has been evaluated. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801829w [article] Trimethylamine-modified lignophenol for the recovery of precious metals [texte imprimé] / Durga Parajuli, Auteur ; Koichi Hirota, Auteur ; Katsutoshi Inoue, Auteur . - 2010 . - pp. 10163–10168. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10163–10168 Mots-clés : Trimethylamine-Modified--Lignophenol--Recovery--Precious--Metals Résumé : A quaternary amine-type sorbent has been prepared by the immobilization of trimethylamine group onto the cross-linked lignophenol matrix. The sorption behavior for a number of metal ions was studied in hydrochloric acid medium. From the batch test of individual metal ion as well as the mixture solution containing equal molar concentration of various metal ions, the sorbent was found to hold selectivity for Au(III), Pd(II), and Pt(IV) ions only with negligible sorption for other metal ions like Cu(II), Co(II), Fe(III), Ni(II), and Zn(II). The sorption kinetics was studied at 30, 50, and 65 °C and elucidated the order of sorption of Au(III), Pd(II), and Pt(IV) and from the values of rate constants at different temperatures, the energy of activation has been evaluated. The sorption isotherm study revealed the Langmuir type sorption and from the Langmuir charts the maximum loading capacity of Au(III), Pd(II), and Pt(IV) has been evaluated. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801829w