Fixed-bed adsorption of reactive azo dye onto granular activated carbon prepared from waste.

Adsorption of hexavalent chromium from aqueous solution by modified corn stalk: A fixed-bed column study

Agricultural solid wastes either in natural or in modified forms have been successfully used for decades as non-conventional cost-effective adsorbents for removing metal ions and dyes from their aqueous phase and have been recognized as a sustainable solution for wastewater treatment. Therefore, this review article provides extensive literature information about heavy metals and dyes, their classifications and toxicity, various treatment methods with emphasis on adsorption characteristics by numerous agricultural solid wastes, or agricultural solid waste-derived adsorbents under various physicochemical process conditions. This review article not only provided an up-to-date information on the application of sustainable low-cost alternative adsorbents such as agricultural solid wastes, agricultural by-products, and biomass-based cost-effective activated carbon and various other natural materials in the batch adsorptive removal of heavy metal and dye from aqueous phase but also presented a comprehensive compilation of adsorptive pollutant removal information based on various reported continuous column operation studies which is one of the new aspect to this review article. The effectiveness of various batch and column operational process parameters on mechanistic adsorptive removal of both heavy metals and dyes by various agricultural solid waste-based adsorbents has been critically discussed here. Batch and column adsorption mechanism, batch kinetics, column dynamic modeling, and adsorptive behavior of adsorbents under various process parameters have also been critically analyzed and compared. Finally, literature information on recovery and regeneration through desorption techniques and cost comparison of various agricultural solid waste adsorbents with commercial activated carbons have also been reported here. Conclusions have been drawn from the literature reviewed, and few suggestions for future research direction are proposed.

A Review on Heavy Metal Ions and Dye Adsorption from Water by Agricultural Solid Waste Adsorbents

Characterization of modified wheat straw, kinetic and equilibrium study about copper ion and methylene blue adsorption in batch mode

Adsorption of methylene blue on adsorbent materials produced from cotton stalk

Adsorption of methylene blue by phoenix tree leaf powder in a fixed-bed column: experiments and prediction of breakthrough curves

A comparison was made of the linear least-squares method and a nonlinear least-square method of the Langmuir isotherm and pseudo second order kinetic model for the biosorption of methylene blue onto rice husk. The parameters obtained from the linear method and the nonlinear method were different. The error analysis was performed. Results showed that both linear and nonlinear method can be used to fit the experimental data. The nonlinear method may be a better way to obtain the desired parameters.

Langmuir Isotherm and Pseudo Second Order Kinetic Model for the Biosorption of Methylene Blue Onto Rice Husk

Wheat husk, an agriculture product, was used to adsorb methylene blue (MB) from aqueous solutions. Variables of the system, including contact time, pH, and equilibrium MB concentration, were adopted to study their effects on MB adsorption. The results showed that as the equilibrium concentration of MB increased, quantity of MB sorption onto wheat husk increased correspondingly. The change of MB adsorbed quantity was very small when the pH was increased from 5.0 to 10.0. The equilibrium data was fitted well by the Langmuir model. The adsorption processes followed the pseudo-second-order rate kinetics. The results in this study indicated that wheat husk was an attractive alternative for removing cationic dyes from the dye wastewater.

Fuling Xie

Papers

Adsorption of methylene blue by phoenix tree leaf powder in a fixed-bed column: experiments and prediction of breakthrough curves

Langmuir Isotherm and Pseudo Second Order Kinetic Model for the Biosorption of Methylene Blue Onto Rice Husk

Adsorption of Methylene Blue from Aqueous Solution by Wheat Husk in Batch Mode