Journal Articles

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https://hdl.handle.net/20.500.14170/296

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Browsing Journal Articles by Subject "Adsorption"
  • Publication
    Metakaolin/sludge based geopolymer adsorbent on high removal efficiency of Cu2+
    ( 2022)
    Pilomeena Arokiasamy
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Shayfull Zamree Abd. Rahim
    ;
    Mohd Remy Rozainy Mohd Arif Zainol
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Marwan Kheimi
    ;
    Jitrin Chaiprapa
    ;
    Andrei Victor Sandu
    ;
    Petrica Vizureanu
    ;
    Rafiza Abd Razak
    ;
    Noorina Hidayu Jamil
    Activated carbon (AC) has received a lot of interest from researchers for the removal of heavy metals from wastewater due to its abundant porous structure. However, it was found unable to meet the required adsorption capacity due to its amorphous structure which restricts the fundamental studies and structural optimization for improved removal performance. In addition, AC is not applicable in large scale wastewater treatment due its expensive synthesis and difficulty in regeneration. Thus, the researchers are paying more attention in synthesis of low cost geopolymer based adsorbent for heavy metal removal due its excellent immobilization effect. However, limited studies have focused on the synthesis of geopolymer based adsorbent for heavy metal adsorption by utilizing industrial sludge. Thus, the aim of this research was to develop metakaolin (MK) based geopolymer adsorbent with incorporation of two types of industrial sludge (S1 and S3) that could be employed as an adsorbent for removing copper (Cu2+) from aqueous solution through the adsorption process. The effects of varied solid to liquid ratio (S/L) on the synthesis of metakaolin/sludge based geopolymer adsorbent and the removal efficiency of Cu2+ by the synthesis adsorbent were studied. The raw materials and synthesized geopolymer were characterized by using x-ray fluorescence (XRF), x-ray diffraction (XRD), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and micro XRF. The concentration of Cu2+ before and after adsorption was determined by atomic absorption spectroscopy (AAS) and the removal efficiency was calculated. The experimental data indicated that the synthesized geopolymer at low S/L ratio has achieved the highest removal efficiency of Cu2+ about 99.62 % and 99.37 % at 25 %:75 % of MK/S1 and 25 %:75 % of MK/S3 respectively compared to pure MK based geopolymer with 98.56 %. The best S/
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  • Publication
    Sulfur dioxide removal using deep eutectic solvent–functionalized palm kernel shell–activated carbon
    (Springer, 2025-02)
    Wan Nur Amanna Wan Nuzi
    ;
    Muhammad Adli Hanif
    ;
    Naimah Ibrahim
    ;
    Farrah Aini Dahalan
    ;
    Nabilah Aminah Lutpi
    ;
    Masitah Hasan
    ;
    Raja Nazrul Hakim Raja Nazri
    ;
    Umi Fazara Md Ali
    The release of SO₂ into the atmosphere is concerning due to its role in acidification, which threatens living organisms and the environment. Adsorption processes using materials like chemically modified activated carbon (AC) have demonstrated strong potential for removing SO₂ before its release. This study evaluates the performance of AC derived from palm kernel shells, and AC functionalized with choline chloride-glycerol, a deep eutectic solvent (DES) (AC-DES), in removing SO₂ through breakthrough experiments conducted in a fixed bed reactor. AC and AC-DES achieved SO₂ adsorption capacities of 0.522 and 2.763 mg SO₂/g adsorbent, respectively. Characterization of the adsorbents indicated that DES functionalization significantly increased the number of active sites for SO₂ adsorption, leading to superior adsorption performance of AC-DES. The optimization of process parameters identified 40 °C and 1500 ppm inlet SO₂ concentration as the ideal conditions for optimal SO₂ adsorption. Experimental data fitted with three adsorption kinetic and isotherm models indicated that SO₂ adsorption onto AC-DES is best described by the Avrami kinetic model and the Sips isotherm model. Thermodynamics studies revealed that the process is exothermic, thermodynamically non-spontaneous, and goes from a random state to an ordered one. The findings suggest that SO₂ adsorption onto AC-DES follows a complex mixed mechanism involving both physisorption and chemisorption, with surface heterogeneity and adsorbate-adsorbent interactions playing a critical role in controlling the adsorption process.