Adsorption of Reactive Blue 19 from aqueous solution by chitin nanofiber-/nanowhisker-based hydrogels

Abstract

Physical hydrogels prepared from partially deacetylated chitin nanofibers/nanowhiskers (DEChNs) were prepared and evaluated as a new adsorbent for Reactive Blue 19 (RB19) solutions. The effects of pH, initial dye concentration, contact time and temperature were investigated. The optimum pH value for the adsorption experiments was found to be 1.0; as pH increases, the dye adsorption capacity decreases gradually. The adsorption of RB19 onto partially deacetylated chitin nanofiber-/nanowhisker-based hydrogels (DEChNs-Gels) was relatively fast, as the equilibrium could be reached in almost 20 min. The maximum adsorption capacity was found to be 1331 mg g), considering the practical applications, the adsorption capacity in pH ¼ 5 (838 mg g À1) was believed to have more practical significance. A pseudo-second-order kinetics model agreed very well with the experimental results. Equilibrium data also fitted well to the Freundlich adsorption isotherm model in this study. The DEChNs-Gels exhibited a high efficiency for removing RB19 from aqueous solutions as a result of their nanofibrillar network and excellent pore structure accompanied by the presence of amino groups. Even when the DDA was lowered to 15%, the adsorption capacity reached 940 mg g À1 due to its nanostructural assembly of nanofibers/nanowhiskers, which showed great advantages compared to highly deacetylated chitosan-based adsorbents (DDA > 70%). Considering the issue of environmental protection and adsorption efficiency, DEChNs-Gels have become a potential substitute for chitosan-based adsorbents due to the milder deacetylation process and superior performance, making this material an attractive adsorbent for textile dyes.

Adsorption of Remazol Brilliant Violet Onto Chitosan 10b in Aqueous Solution: Kinetics, Equilibrium and Thermodynamics Studies

“…The Dubinin-Radushkevich isotherm equation used to estimate the characteristic porosity of the adsorbent and the apparent energy of adsorption, which is given by Equation (15): (15) Equation (15) can be expressed in its linear form as: (16) Polanyi potential (ε) is given as Equation (17): (17) The plot of lnq e versus ε 2 gives a straight line with a slope of -K DR and an intercept of lnq DR . The Dubinin-Radushkevich constant can give valuable information regarding the mean energy of adsorption by Equation (18): (18) The calculated parameters and correlation coefficients are listed in Table 3. The correlation coefficients (R 2 ) of the Dubinin-Radushkevich isotherm are 0.978, 0.918, 0.915 and 0.968 at 31, 36, 41 and 46 °C, respectively.…”

“…In recent years, biomass has been accepted as an appropriate low-cost adsorbent for the removal of dyes from aqueous solution. Many types of natural and modified biomass, such as biochars, 13 mango leaves, 14 Daucus carota, 15 Irvingia gabonenses, 16 agricultural by-products, 17 chitin, 18 chitosan [19][20][21][22][23] and functionalized chitosan, [24][25][26] have shown promising results in dye adsorption applications. However, related reports on utilizing chitosan to remove Remazol Brilliant Violet (RBV; Fig.…”

Microbial Conversion of Shrimp Heads to Proteases and Chitin as an Effective Dye Adsorbent

“…Since dyes are commonly used in many industries, such as the food industry, the textile industry, the paper pulp industry, etc., they are one of the most considerable contributors to water pollution. In addition, dye-containing wastewater is known to be potentially toxic to the environment and difficult to remove [ 36 , 37 , 38 ]. Several methods are effective in dye removal, such as oxidation, adsorption, ultrafiltration, and coagulation, and due to its high performance, flexibility, and minimal energy requirements, adsorption is one of the most appropriate methods for dye effluent treatment [ 38 ].…”

Adsorption of aniline from aqueous solution using graphene oxide-modified attapulgite composites

“…14,15 With the selection of a proper adsorbent, the adsorption process can be a promising technique for the removal of aniline from wastewater. Compared with other adsorbents such as the activated carbons, 16 the silica gels, 17,18 metal-organic framework materials 19 and polymeric materials, 20,21 attapulgite (ATP), which is a natural clay mineral that is found in many places of the world, is viewed as a more attractive alternative due to its low-cost and environment friendly characters. ATP is widely used to adsorb a wide range of toxic derivatives from aqueous solution.…”