Preparation of activated carbons from peach stone by H₄P₂O₇ activation and its application for the removal of Acid Red 18 and dye containing wastewater

ABSTRACT

The present study consists of the preparation of activated carbon from peach stone (PSAC) by H₄P₂O₇ activation and its detailed characterization. The influence of different activants and various operational conditions including; soaking time, activation time, and activation temperature during PSAC preparation were systematically investigated. The chemical properties and morphology of prepared activated carbon was characterized by various analytical techniques (FTIR, SEM and EDX). TG-DTA analysis showed that the pore development of PSAC was significant at temperatures > 450°C. The prepared PSAC were utilized for the rapid removal and adsorption of Acid Red 18 (AR18) from aqueous solution that follows pseudo–second-order kinetics. The Langmuir isotherm model corresponded well with equilibrium data than the others, implying that the adsorption of AR18 onto prepared PSAC from the aqueous solutions proceeds by a monolayer formation. Thermodynamic investigations showed that the adsorption process is an exothermic and spontaneous process. During reusability studies, PSAC showed complete removal of AR18 upto seventh cycle increasing its practical applicability. Finally the prepared PSAC showed the best adsorptive capacity as compared to commercial AC for dye removal from actual industrial wastewater. This confers the possibility of applying PSAC economically viable option for the treatment of industrial wastewaters containing dye pollutants using suitable reactor.

KEYWORDS:

• Acid Red 18
• activated carbon (AC)
• adsorption
• isotherm
• dye wastewater kinetics study
• peach stone
• pyrophosphoric acid

Funding

The project was supported by the Fundamental Technology R & D Program for Society of the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (Grant number: 2013 M3C8A3078596 and 2009-0083527).