Adsorption of Pb(II) Ions on Sulfuric Acid Treated

Sulfuric acid treated Petai belalang (Leucaena leucocephala) leaf powder (SLLP) was used as an adsorbent for Pb(II) ions removal. The experimental adsorption parameters investigated include pH, dosage and initial Pb(II) concentration. Pb(II) removal was more favored at a higher adsorbent dosage, pH and temperature. Adsorption kinetics conformed to the pseudo-second order model while Langmuir isotherm model recorded the value of maximum adsorption capacity (qmax) of 222 mg/g. The major functional groups involved in the adsorption process were identified as hydroxyl, amino and ether as revealed by the FTIR analysis. The prepared adsorbent demonstrated a potential application for efficient removal of Pb(II) ions from industrial wastewater

Adsorption of Pb(II) Ions on Sulfuric Acid Treated Leucaena leucocephala Leaf Powder

Sulfuric acid treated Petai belalang (Leucaena leucocephala) leaf powder (SLLP) was used as an adsorbent for Pb(II) ions removal. The experimental adsorption parameters investigated include pH, dosage and initial Pb(II) concentration. Pb(II) removal was more favored at a higher adsorbent dosage, pH and temperature. Adsorption kinetics conformed to the pseudo-second order model while Langmuir isotherm model recorded the value of maximum adsorption capacity (qmax) of 222 mg/g. The major functional groups involved in the adsorption process were identified as hydroxyl, amino and ether as revealed by the FTIR analysis. The prepared adsorbent demonstrated a potential application for efficient removal of Pb(II) ions from industrial wastewater

Comparative Adsorption of Methylene Blue Dye on Hexane-Washed and Xanthated Spent Grated Coconut (Cocos nucifera L.): Isotherms, Thermodynamics, and Mechanisms

A batch system investigated the application of two types of chemically modified biosorbents derived from spent grated coconut (Cocos nucifera) powder to adsorb methylene blue (MB) from aqueous solutions. The biosorbents were characterised by spectroscopic and quantitative analyses. The assessment of MB adsorption onto the investigated biosorbents was studied at different experimental conditions with different pHs (2–9) and different initial concentrations of MB (10–400 mg/L) at three different temperatures (298, 308, and 318 K). The maximum adsorption capacity (qmax) of xanthated spent grated coconut (XSGC) was higher than that of hexane-washed spent grated coconut (HSGC). The thermodynamic study indicated that the MB adsorption process was spontaneous for both biosorbents. Desorption of MB-loaded biosorbents was carried out using HCl, NaOH, and Na2EDTA solutions. A desorption ratio of more than 90% was obtained over three adsorption/desorption cycles for HSGC. However, XSGC demonstrated poor MB desorption, implying a stronger MB interaction with XSGC, which could be attributed to H-bonding, Yoshida H-bonding, n-π, and π-π bonding. The study showed that HSGC and XSGC could be applied as biosorbents to remove low MB concentrations from aqueous solutions

Variable filtered photographic film as a radiation detector for environmental radiation monitoring

Environmental radiation is an ionising radiation that present in the natural environment which mostly originates from cosmic rays and radionuclide agents in the environment. This may lead the population to be exposed to the radiation. Therefore, the environmental radiation needs to be observed cautiously to minimize the impact of radiation. However, there is no specific or proper monitoring device that provides an outdoor environmental radiation monitoring. Hence, a new outdoor environmental radiation monitoring device was developed. A photographic film has been chosen as a dosimeter. The purpose of this study was to prove the covered photographic film attached with variable filter can be used to develop environmental radiation monitoring device to detect the ionising radiation. The filter used was variable thickness of plastic, aluminium (Al) and lead (Pb). The result from the study showed that the mean optical density (OD) values for medium speed film are in the range 0.41 to 0.73, and for fast speed film the OD values are in the range 0.51 to 1.35. The OD values decreased when the filter was attached. This has proven that the photographic film can be used to detect radiation and fast speed film was more sensitive compared to medium speed film

Hydrogen Peroxide Treated Desiccated Coconut Waste as a Biosorbent in Malachite Green Removal from Aqueous Solutions

Malachite green (MG), commonly employed in the textile and dyeing sectors, is a prevalent and enduring contaminant found in wastewater and the environment. Its presence poses harmful effects to humans and aquatic organisms. This work utilised hydrogen peroxide-treated desiccated coconut waste (HPDCW) to remove MG from an aqueous solution. The HPDCW underwent characterisation utilising FTIR, SEM-EDX, pHslurry, and pHpzc. Based on the results obtained, it was found that HPDCW recorded a biosorption capacity of 211.88 mg/g, attained at a temperature of 302 K, a pH of 9, a contact period of 5 min, and a dosage of 0.02 g. MG biosorption rates accurately followed the pseudo-second-order kinetic model, while the equilibrium data presented a step-shaped isotherm model. The relatively small percentages of MG desorption observed when using distilled water and HCl (0.01 and 0.02 M) indicate that electrostatic interaction is one of the mechanisms responsible for the interaction between MG and HPDCW. There is also a possibility of the involvement of hydrogen bonding and π-π interactions

Acid blue 25 adsorption on base treated Shorea dasyphylla sawdust: kinetic, isotherm, thermodynamic and spectroscopic analysis

The potential of base treated Shorea dasyphylla (BTSD) sawdust for Acid Blue 25 (AB 25) adsorption was investigated in a batch adsorption process. Various physiochemical parameters such as pH, stirring rate, dosage, concentration, contact time and temperature were studied. The adsorbent was characterized with Fourier transform infrared spectrophotometer, scanning electron microscope and Brunauer, Emmett and Teller analysis. The optimum conditions for AB 25 adsorption were pH 2, stirring rate 500 r/min, adsorbent dosage 0.10 g and contact time 60 min. The pseudo second-order model showed the best conformity to the kinetic data. The equilibrium adsorption of AB 25 was described by Freundlich and Langmuir, with the latter found to agree well with the isotherm model. The maximum monolayer adsorption capacity of BTSD was 24.39 mg/g at 300 K, estimated from the Langmuir model. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that AB 25 adsorption was spontaneous and exothermic

Adsorption behavior of PB(II) onto xanthated rubber (Hevea brasiliensis) leaf powder

A plant waste, rubber (Hevea brasiliensis) leaf powder was modified with carbon disulfide (xanthation) for the purpose of introducing sulfur groups, and the adsorbent performance in removing Pb(II) ion was evaluated. Pb(II) adsorption was confirmed by spectroscopic analysis, which involved Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The amount of Pb(II) adsorbed increased with increasing pH, contact time and concentration but slightly decreased with increasing ionic strength. Adsorption equilibrium was achieved in less than 60 min and followed the pseudo-second order model. The isotherm data indicated that Pb(II) adsorption on xanthated rubber leaf (XRL) fitted well with Langmuir isotherm model. The maximum adsorption capacity computed from the Langmuir isotherm model was 166.7 mg/g. Pb(II) adsorption occurred via ion-exchange and complexation mechanisms