Alkaline treatment of timber sawdust: A straightforward route toward effective low-cost adsorbent for the enhanced removal of basic dyes from aqueous solutions
Autor: | El Hadj Elandaloussi, Abdallah Aziz, Yamina Djilali, Louis-Charles de Ménorval |
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Přispěvatelé: | Laboratoire de Valorisation des Materiaux, Université de Mostaganem, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC) |
Jazyk: | angličtina |
Rok vydání: | 2012 |
Předmět: |
Chemistry(all)
02 engineering and technology 010501 environmental sciences Lignocellulosics 01 natural sciences Isotherms lcsh:Chemistry symbols.namesake chemistry.chemical_compound Adsorption Desorption Organic chemistry Regeneration 0105 earth and related environmental sciences Aqueous solution Chemistry Cationic polymerization Langmuir adsorption model Sorption General Chemistry [CHIM.MATE]Chemical Sciences/Material chemistry 021001 nanoscience & nanotechnology Color removal lcsh:QD1-999 Chemical engineering visual_art visual_art.visual_art_medium symbols Alkaline treatment Sawdust 0210 nano-technology Methylene blue |
Zdroj: | Journal of Saudi Chemical Society Journal of Saudi Chemical Society, Elsevier, 2012, pp.220-226. ⟨10.1016/j.jscs.2012.10.013⟩ Journal of Saudi Chemical Society, Vol 20, Iss S1, Pp S241-S249 (2016) |
ISSN: | 1319-6103 |
Popis: | International audience; The present study assesses the ability of two low-cost adsorbents - timber sawdust (TS- OH) and its alkaline treated analog (TS-ONa) - to remove two basic dyes, namely, Methylene Blue and Methyl Green, from aqueous solutions. The presence of new functional groups on the surface of TS-ONa resulted in a dramatic increase of surface polarity and the density of sorption sites, thereby improving the sorption efficiency of the cationic dyes. The results obtained from the sorp- tion characteristics have revealed that the sorption process for TS-ONa was uniform and rapid. The adsorption of cationic dyes reached equilibrium within the first 10 min of contact time and the trea- ted material acts efficiently in a wide pH range of dye solutions. The extent of adsorption was mea- sured through equilibrium sorption isotherms and analyzed using the Langmuir model. The monolayer saturation capacities for Methylene Blue are 694.44 and 1928.31 mg/g and for Methyl Green are 892.86 and 1821.33 mg/g for TS-OH and TS-ONa, respectively. Therefore, the chem- ically treated sawdust proved two- to threefold higher adsorption capacities of these dyes than those of the untreated analog. The exothermic nature of adsorption is demonstrated by a decrease of adsorption capacity with increasing temperature, and the negative value of free energy change indi- cated the spontaneity of adsorption. Desorption experiments with 1 M aqueous NaCl put into evi- dence that cationic dyes were completely desorbed from the matrices and the reusability of the TS- ONa matrix after three repeated cycles led to just a slight attenuation in its performance. These results show that alkaline treatment of a low value by-product of the timber industry leads to a powerful and efficient low-cost adsorbent, which may be used for the treatment of colored waste- waters. |
Databáze: | OpenAIRE |
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