| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 222328 | Journal of Environmental Chemical Engineering | 2015 | 11 Pages |
•Porous carbon from waste tea for adsorption of cationic and anionic dye.•Very high surface area of 2054.49 m2 g−1 with pore volume 1.747 cm3 g−1.•Effective at neutral pH with adsorption performance >99%.•The max adsorption capacity for MB and EY are 402.25 mg g−1 and 400 mg g−1.•The adsorption kinetics follows a pseudo-second-order pathway.
Porous carbon with high surface area was synthesized from different tea precursors under thermochemical condition in presence of phosphoric acid as activating agent. The synthetic procedure was optimized under different condition of acid impregnation ratio, heating temperature, dwelling time, etc. Pore morphology, surface properties, crystalline nature and thermal stability of porous carbon (PC) were assessed by using BET, SEM, FTIR, XRD and TGA analysis. Under optimized synthetic condition, the maximum surface area of the carbon material was found to be 2054.49 m2 g−1 with a total pore volume of 1.747 cm3 g−1. Adsorption characteristics of the PC for removal of a cationic dye (methylene blue) and an anionic dye (eosin yellow) were investigated spectrophotometrically as a function of initial dye concentration and contact time, adsorbent dosage, solution pH and temperature, etc. The PC was found to be equally efficient for removal of both the dyes from aqueous solutions at neutral pH with adsorption performance of greater than 99%. The equilibrium adsorption data of both the dyes could be described well by the Langmuir isotherm equation. The maximum adsorption capacity for methylene blue and eosin yellow was found to be 402.25 mg g−1 and 400 mg g−1, respectively. The adsorption kinetics in case of both the dyes follows a pseudo-second-order pathway. Investigations on thermodynamic parameters in the temperature range of 303–323 K revealed that the adsorption process is spontaneous and endothermic in nature.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slidePorous carbon with high surface area was synthesized from tea precursors under thermochemical condition in presence of phosphoric acid as activating agent. Under optimized synthetic condition, the maximum surface area of the carbon material was found to be 2054.49 m2 g−1 with a total pore volume of 1.747 cm3 g−1. The PC was found to be equally efficient for removal of both the dyes from aqueous solutions at neutral pH with adsorption performance of greater than 99%. The maximum adsorption capacity for methylene blue and eosin yellow was found to be 402.25 mg g−1 and 400 mg g−1, respectively. The adsorption kinetics in case of both the dyes follows a pseudo-second-order pathway. Investigations on thermodynamic parameters in the temperature range of 303–323 K revealed that the adsorption process is spontaneous and endothermic in nature.
