Efficient Adsorption of Methyl Orange Using a Modified Chitosan Magnetic Composite Adsorbent

Abstract

Glutaraldehyde cross-linked chitosan-coated Fe 3 O 4 nanocomposites (MCNPs) were successfully synthesized for the removal of methyl orange (MO) from wastewater. Experimental conditions such as the pH, cation surfactant dosage, nanoadsorbent dosage, and ionic strength were also investigated. Kinetics date was better fit by a pseudosecond-order model, indicating that adsorption was the ratelimiting step. The Freundlich models (R 2 = 0.9794) fit the experimental data better than the Langmuir models, and the theoretical maximum adsorption capacity was 758 mg g −1 . The values of the Gibbs free energy (ΔG°= −7.27 kJ mol −1 ), enthalpy (ΔH°= 0.001 kJ mol −1 ), and entropy (ΔS°= 23.58 J mol −1 ) indicated the spontaneous and endothermic process of MO adsorption. The prepared MCNPs showed 96−98% adsorption of MO by adding 0.2 mg of cationic surfactant cetyltrimethylammonium bromide (CTAB) to form mixed hemimicelles and can be easily regenerated with a 0.1 mol L −1 HCl solution.

Iron Oxide/Chitosan Magnetic Nanocomposite Immobilized Manganese Peroxidase for Decolorization of Textile Wastewater

“…Therefore, dyes must be removed before effluent discharge into the environment, as these molecules are hard to decompose in natural conditions (pH, temperature, etc.) or with conventional methods of treatment [9].…”

Processing–structure–property relationship in direct laser writing carbonization of polyimide

“…As explained in the Experimental Section, the specific quantity was obtained by using the nominal area rather than the mass of the carbon line as the normalization factor. As shown in Figure , the adsorption isotherm results for all samples being measured can be fitted by a Langmuir monolayer adsorption model, where q e is the mass of MB adsorbed per unit area of carbon line (mg cm −2 ) at an equilibrium solution concentration C e (μM); q max is the theoretical maximum adsorption capacity (mg cm −2 ); and K L (μM −1 ) is the Langmuir adsorption constant. The fitting parameters of q max and K L are listed in Table S1.…”

Azo-dye adsorption activity of iron(III) loaded novolac-based network sorbents

“…Recently, polymer/inorganic hybrid materials have attracted interest to remove trace pollutants from waters. [24,30] Their unique properties arise from the combination of both polymer and inorganic characteristics. Novolac-based network polymers 1a and 2a deserve particular attention in loading metal ions especially ferric minerals, due to the nonhydrolyzable polyfunctionality in combination with the feature of novolac structural support providing mechanical, chemical, and thermal strength.…”

“…[6][7][8][9][10][11][12][13][14][15][16][17] Among these methodologies, adsorption-based process [6][7][8] has received increasing interest because of its economics, design simplicity and efficiency in minimizing pollutants. Polymeric sorbents [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] enjoy exclusive attributes namely low density, high thermal and/or chemical stability, mechanical rigidity, wide variations in porosity and surface functionality tailoring, high adsorption capability, easy handling and feasible regeneration. Phenolic resins due to their low-cost, easy availability, and dimensional stability, are popular for innovative applications in various domains.…”