Efficient Removal of Methyl Blue Using Nanoporous Carbon from the Waste Biomass

Abstract

The nanoporous carbon using waste straw as carbon source was well prepared for effective dye removal from aqueous solution. The structure and surface properties of nanoporous carbon were characterized by X-ray diffraction, Raman spectroscopy, N₂ adsorption–desorption, and X-ray photoelectron spectroscopy. The results revealed that the nanoporous carbon exhibited large specific surface area and porous structure with abundant functional groups on the surface. In the adsorption experiments, the nanoporous carbon showed high dye adsorption capacity and rapid removal rate under higher pH value, initial dye concentration, and dosage of adsorbents. Moreover, the adsorption isotherm data fitted well to the Langmuir model, suggesting the monolayer adsorption. The maximum adsorption capacity could reach 555.56 mg/g, much higher than the recent reports. Besides, the adsorption kinetics fitted well to the pseudo-second-order model and the correlation coefficients were greater than 0.999. Thermodynamic study results indicated that dye adsorption onto the hierarchical nanoporous carbon was spontaneous and thermodynamically favorable. Therefore, with larger specific surface area and porous structure, the nanoporous carbon showed great potential as efficient adsorbents for dye in the aqueous environment.

from #ORL-AlexandrosSfakianakis via ola Kala on Inoreader http://ift.tt/2FvnzuC