Characterization, isotherm and kinetic data for adsorption of Congo red and 2-naphthol on different bamboo hydrochars.

Hydrochars were prepared using bamboo sawdust as raw material through hydrothermal carbonization with the present of acid or alkali in the medium and applied to remove Congo red and 2-naphthol from aqueous solutions. This data article provides information on FTIR and SEM profiles of the bamboo hydrochars, and the equation fitting results of the adsorption isotherms and kinetics for the two organics. The FTIR spectra show the differences of functional groups on the hydrochars with different process conditions. The SEM images show the surface morphology of selected hydrochars. Freundlich equation is slightly better than Langmuir model for the correlation of adsorption isotherms for both Congo red and 2-naphthol. Correlation coefficients from the pseudo-second order equation are greater than those of the pseudo-first order equation for both the organics on selected hydorchars.

Hydrochars from bamboo sawdust through acid assisted and two-stage hydrothermal carbonization for removal of two organics from aqueous solution.

A series of bamboo hydrochars were prepared through acid-assisted and two-stage hydrothermal carbonization, characterized and evaluated for the adsorption of Congo red and 2-naphthol in aqueous solutions. The hydrochars have rough surfaces with BET surface areas of 6.77-57.74 m2/g and oxygen-rich functional groups. The additives in feed water revealed critical influences on the physical-chemical and adsorption properties of the hydrochars. The hydrochars can adsorb the two organics effectively, the highest adsorption capacities for Congo red and 2-naphthol are 90.51 and 72.93 mg/g, respectively, at 0.1 mg/mL and 298 K. The adsorption of the two organics on the selected hydrochars is a spontaneous and mainly physical adsorption process. 95% and 92% of the adsorption equilibrium could be accomplished in one hour for Congo red and 2-naphthol on the selected hydrochars, respectively. This study provides references for the production and application of hydrochars as efficient adsorbents in wastewater treatment.

Production and optimization of bamboo hydrochars for adsorption of Congo red and 2-naphthol.

Twelve hydrochars were produced from bamboo sawdust for adsorption of Congo red and 2-naphthol. The bamboo hydrochars have Brunauer-Emmett-Teller (BET) surface areas ranging from 2.63m(2)/g to 43.07m(2)/g, average pore diameters from 3.05nm to 3.83nm, pore volumes between 0.02cm(3)/g and 0.53cm(3)/g, and the surfaces of the hydrochars have diverse functional groups. The physico-chemical properties of the hydrochars critically depend on the hydrothermal conditions. All the hydrochars can adsorb Congo red and 2-naphthol from aqueous solutions, the largest adsorption capacity for Congo red is 33.7mg/g at the equilibrium concentration of 0.1mg/mL at 25°C, and the highest adsorption amount for 2-naphthol is 12.2mg/g at 25°C and 0.1mg/mL. Freundlich model can describe the adsorption isotherms of the both adsorbates slightly better than Langmuir model. These results provide a reference to the production and use of hydrochars as potential adsorbents in wastewater treatment.