Decolorization of eosin-Y dye using activated carbon electrode prepared from bael fruit (Aegle marmelos) shell

摘要

In the present scenario, electrode materials used in electrochemical processes are moderately expensive; hence, low-cost electrode material obtains more importance. The current study examined the potential of electroadsorption of eosin-Y dye on activated carbon electrode (ACE) and carbon composite electrode (CCE) prepared from bael fruit (Aegle marmelos) shell (BS). This study holds the novelty of ACE prepared from BS carbon using H3PO4 activation, and also compositing technique was adopted to improve the conductivity of the ACE. In addition to good electrical conductivity, the electrode prepared is also cost-effective. The factors like applied potential, contact time and initial dye concentration were varied to obtain specific information about the influence of them on the adsorption ability and adsorption equilibrium. UV-visible spectrophotometric analysis method was used to find the capacity of eosin-Y dye color removal. Surface area and pore volume analysis were carried out using Brunauer-Emmett-Teller apparatus. The other characterization of the activated carbon, ACE and CCE were done using different analytical instruments like scanning electron microscope for surface morphology, energy-dispersive X-ray spectroscopy for elemental investigation and thermogravimetric analysis for thermal stability of BS adsorbent. The isotherm models as Langmuir, Freundlich and Jovanovic were used to analyze the equilibrium data of electrosorption. Freundlich isotherm was found to be the most suitable with a correlation coefficient (R-2 = 0.923). Kinetic studies were performed for pseudo-first-order, pseudo-second-order and intraparticle diffusion model. The experimental data were found to fit well with the pseudo-first-order kinetic model, with R-2 = 0.969. It has been observed that modifications in surface properties of electrode play a major role in dye wastewater treatment processes. The results showed that the CCE is best suitable for the application of dye color removal compared with ACE, using electrosorption techniques.