Dataset Information

Chitosan-Silica Composites for Adsorption Application in the Treatment of Water and Wastewater from Anionic Dyes.

ABSTRACT: A series of new types of composites (biopolymer-silica materials) are proposed as selective and effective adsorbents. A new procedure for the synthesis of chitosan-nanosilica composites (ChNS) and chitosan-silica gel composites (ChSG) using geometrical modification of silica and mechanosorption of chitosan is applied. The highest adsorption efficiency was achieved at pH = 2, hence the desirability of modifications aimed at stabilizing chitosan in such conditions. The amount of chitosan in the synthesis grew to 1.8 times the adsorption capacity for the nanosilica-supported materials and 1.6 times for the silica gel-based composites. The adsorption kinetics of anionic dyes (acid red AR88) was faster for ChNS than for ChSG, which results from a silica-type effect. The various structural, textural, and physicochemical aspects of the chitosan-silica adsorbents were analyzed via small-angle X-ray scattering, scanning electron microscopy, low-temperature gas (nitrogen) adsorption, and potentiometric titration, as well as their adsorption effectiveness towards selected dyes. This indicates the synergistic effect of the presence of dye-binding groups of the chitosan component, and the developed interfacial surface of the silica component in composites.

SUBMITTER: Blachnio M

PROVIDER: S-EPMC10380244 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Chitosan-Silica Composites for Adsorption Application in the Treatment of Water and Wastewater from Anionic Dyes.

Blachnio Magdalena M Zienkiewicz-Strzalka Malgorzata M Derylo-Marczewska Anna A Nosach Liudmyla V LV Voronin Eugeny F EF

International journal of molecular sciences 20230723 14

A series of new types of composites (biopolymer-silica materials) are proposed as selective and effective adsorbents. A new procedure for the synthesis of chitosan-nanosilica composites (ChNS) and chitosan-silica gel composites (ChSG) using geometrical modification of silica and mechanosorption of chitosan is applied. The highest adsorption efficiency was achieved at pH = 2, hence the desirability of modifications aimed at stabilizing chitosan in such conditions. The amount of chitosan in the sy ...[more]

PMID: 37511577

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Dataset Information

Chitosan-Silica Composites for Adsorption Application in the Treatment of Water and Wastewater from Anionic Dyes.

Publications

Chitosan-Silica Composites for Adsorption Application in the Treatment of Water and Wastewater from Anionic Dyes.

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