Norsuria Mahmed
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Preferred name
Norsuria Mahmed
Official Name
Norsuria, Mahmed
Alternative Name
Mahmed, Norsuria
Mahmed, N.
Norsuria, Mahmed
Norsuria, M.
Main Affiliation
Scopus Author ID
24802694300
Researcher ID
FOC-8505-2022

Research Output
Now showing 1 - 3 of 3
  • Publication
    Adsorption efficiency and photocatalytic activity of silver sulphide-activated carbon (Ag₂S-AC) composites
    (Elsevier B.V., 2025)
    Siti Norsaffirah Zailan
    ;
    Norsuria Mahmed
    ;
    Aissa Bouaissi
    ;
    Zahra Ramadlan Mubarokah
    ;
    Mohd Natashah Norizan
    ;
    Nurfina Yudasari
    ;
    Ili Salwani Mohamad
    ;
    Siti Salwa Mohammad Shirajuddin
    Background: This study investigates the adsorption efficiency and photocatalytic activity of silver sulphide-activated carbon (Ag₂S-AC) composites derived from ground coffee waste (GCW). Methods: In this work, GCW was preceding to carbonized at 500 ± 2°C for hours and formed biochar. Then, GCW was subjected to activation using hydrochloric acid (HCl), phosphoric acid (H₃PO₄) and potassium hydroxide (KOH). The mixture was left to soak for 24 h at room temperature, followed by carbonization at 350 and 500˚C. In the meantime, the silver sulphide (Ag₂S) was synthesized by using an ion exchange method. Sodium sulphide (Na₂S) was used as sulphur source and mixed with silver nitrate (AgNO₃) and sodium citrate (NaCit) for two hours, then dried in oven at 50 ± 2°C for 10 h. Next, the carbonized AC was subsequently combined with synthesized silver sulphide, resulting in the creation of Ag₂S-activated carbon composites that functioned both as adsorbent and photocatalyst. Their capabilities as adsorbents and photocatalyst were studied by using copper ions (Cu2+) and methylene blue (MB) solution. Significance findings: Based on results, GCW and all the prepared activated carbons are in the amorphous phase, except for the Ag₂S-AC composites, where the Ag₂S peak reflection can be observed from the X-ray diffraction (XRD) pattern. GCW shows rough and dense surface morphology. The AC shows different pore sizes and structures depending on the chemical activators used, where AC-KOH shows the largest pore size (165.31 μm). The existence of micropores can be observed in all the activated carbon samples. For the adsorption of Cu2+, all samples show more than 99 % of the removal efficiency. While for photocatalytic testing, the Ag₂S-H₃PO₄ sample shows the highest degradation rate (97.7 %) of MB solutions.
  • Publication
    Magnetite (Fe₃O₄)-activated carbon composite from ground coffee waste for the removal of copper ions (Cu²⁺) from solution
    ( 2024-12)
    Siti Norsaffirah Zailan
    ;
    Norsuria Mahmed
    ;
    Nur Mawaddah Juzaini
    ;
    Mohd Natashah Norizan
    ;
    Ili Salwani Mohamad
    ;
    Aissa Bouaissi
    The influence of the magnetite addition on the adsorption efficiency of activated carbon (AC) synthesized using different activators was investigated. In this work, the activated carbon from ground coffee waste (GCW) was prepared via activation with phosphoric acid (H3PO4) and potassium hydroxide (KOH), followed by carbonization at 500˚C. The magnetite (Fe₃O₄)-activated carbon composites were prepared by mixing the activated carbon with Fe₃O₄ powders. From the X-ray diffraction analysis, both activated carbons produced by H₃PO₄, and KOH are in the form of amorphous structures. Magnetite peaks can be observed from the magnetite-activated carbon composites. KOH-treated activated carbon shows the formation of porous honeycomb-like structures with large pore size (average diameter ±43 𝛍m) compared to H3PO4-treated activated carbon where the smaller, non-uniform pore morphology with the average diameter ±32 𝛍m was formed. The copper ions removal efficiency is the highest for biochar (almost 100%). For treated activated carbon, AC-KOH and MAC-KOH shows the highest adsorption removal efficiency (99.7%) compared to the acid-treated carbon (91.9%). Magnetite itself has good adsorption behaviour (93.6% efficiency) due to its nanocrystalline structure (high surface area) and functional groups.
      18  2
  • Publication
    Ground coffee waste-derived activated carbon a sustainable adsorbent and photocatalyst for effective methylene blue dye degradation
    ( 2024-12)
    Or Yang Jai Xien
    ;
    Siti Norsaffirah Zailan
    ;
    Norsuria Mahmed
    ;
    Mohd Natashah Norizan
    ;
    Ili Salwani Mohamad
    This study focuses on harnessing the potential of ground coffee waste (GCW) as a valuable precursor to produce activated carbon (AC) through pyrolysis. The objective is to develop an eco-friendly adsorbent and photocatalyst for environmental remediation applications. Preceding pyrolysis at 350°C for 3.5 hours, GCW was subjected to activate using hydrochloric acid (HCl) and potassium hydroxide (KOH). The resulting AC was subsequently combined with titanium dioxide (TiO2) photocatalyst powder, resulting in the creation of TiO2-AC composites that functioned both as adsorbent and photocatalyst. The TiO2-AC composites were investigated for their adsorption and photocatalytic capabilities in the degradation of 10 ppm methylene blue dye under sunlight exposure for 240 minutes. Morphological analysis revealed a sponge-like structure for both HCl-activated AC and NaOH-activated AC, with HCl-AC exhibiting more pronounced and uniform pores compared to KOH-AC. Remarkably, GCW demonstrated the highest removal efficiency, effectively removing 97.34% of methylene blue, outperforming HCl-AC (16.89%) and KOH-AC (10.41%). Nonetheless, the AC-TiO2 composites, specifically HCl-AC/TiO2 and KOH-AC/TiO2, also exhibited considerable removal efficiencies of 93.31% and 92.46%, respectively. These findings underscore the promising potential of utilizing GCW-derived activated carbon as an environmentally sustainable solution for organic pollutant treatment and herald its significance in promoting greener approaches to waste utilization and environmental protection.
      5  23