Utilization of renewable durian peels for biosorption of zinc from wastewater

Abstract

Durian peel is among the renewable biomass wastes abundantly available in Malaysia. An implication of untreated biological materials for biosorption process was intensively reported, that prioritize our work towards sorbent modification. The biosorption potentials of hydrochloric acid (HCl) modified durian peels (HAMDP) for removal of Zn (II) from simulated wastewater was investigated. Characterization of HAMDP was performed by ATR-FTIR, SEM and BET. Spectroscopic studies showed the predominant contributors for Zn (II) biosorption on HAMDP is attributed to hydroxyl, carbonyl, carboxyl and amides groups. Batch adsorption studies revealed optimum conditions of pH 8, 0.5 g biosorbent dose, 4 h contact time and reaction temperature of 313 K. Nonlinear isotherm models suggested applicability of Tempkin and Langmuir models at 313 K. The Langmuir maximum adsorption capacity was 36.73 mg/g. Kinetic studies revealed applicability of pseudo-second-order model. Webber-Morris model indicated possible role of diffusion of Zn (II) within the particles of HAMDP during the sorption process. Freundlich constant and activation energy values confirmed the physical nature of the process. Thermodynamic studies indicated that the process is exothermic and spontaneous. Regeneration studies depicted that HAMDP is economically viable. Conclusively, HCl served two significant purposes, namely; a good modification reagent and best eluent in Zn (II) recovery. Therefore, HAMDP is relatively effective, efficient, economical and most importantly "renewable and sustainable" biosorbent for Zn (II) removal from wastewater.

Optimization and activation of renewable durian husk for biosorption of lead (II) from an aqueous medium

“…A degas temperature of 200 °C was used to determine BET surface area, pore diameter and the pore volume of DHAC. Additionally, the surface area of pristine durian husk was also determined in order to compare with that of DHAC.…”

“…Attenuated total reflection‐Fourier transform‐infrared (ATR‐FTIR) (Perkin Elmer Spectrum 100 FTIR Spectrometer, USA) spectroscopy was used to determine the functional groups present on the surface of the DHAC active in biosorption of Pb(II) from the synthetic solution. The spectra of non‐modified durian husk/peel was previously published . The characterizations of DHAC before and after Pb(II) adsorption was analyzed within the wavelength range 4000–650 cm −1 .…”

“…The surface morphology of the raw durian husk before activation, DHAC before Pb(II) adsorption, DHAC after Pb(II) adsorption as well as after Pb(II) desorption was determined by scanning electron microscopy (SEM Model S‐3400N, Hitachi High‐Technologies Co., Japan) addition, surface area and pore size of pristine biosorbent, and DHAC were examined using the Brunauer, Emmett and Teller (BET) single point method. It was analyzed with surface characterization analyzer (Model 170, Micromeritics 3 flex 1.02, USA) degas temperature of 200 °C was adopted , and the samples were out‐gassed by passing dry nitrogen for a specific duration over the samples in order to clean any unwanted matter, e.g. moisture content or dust particles that would interfere, especially by blocking the pores available on the surface of the biosorbent .…”

“…It was analyzed with surface characterization analyzer (Model 170, Micromeritics 3 flex 1.02, USA) degas temperature of 200 °C was adopted , and the samples were out‐gassed by passing dry nitrogen for a specific duration over the samples in order to clean any unwanted matter, e.g. moisture content or dust particles that would interfere, especially by blocking the pores available on the surface of the biosorbent . Proximate analysis of the cellulosic raw durian husk RDH, and DHAC were performed using a thermo gravimetric analyzer (TGA) equipment (Model Perkin Elmer TGA7, USA).…”

“…The spectra of non-modified durian husk/peel was previously published. 27 The characterizations of DHAC before and after Pb(II) adsorption was analyzed within the wavelength range 4000-650 cm −1 . The surface morphology of the raw durian husk before activation, DHAC before Pb(II) adsorption, DHAC after Pb(II) adsorption as well as after Pb(II) desorption was determined by scanning electron microscopy (SEM Model S-3400N, Hitachi High-Technologies Co., Japan) addition, surface area and pore size of pristine biosorbent, and DHAC were examined using the Brunauer, Emmett and Teller (BET) single point method.…”