Siti Khalijah Mahmad Rozi
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Siti Khalijah Mahmad Rozi
Official Name
Siti Khalijah, Mahmad Rozi
Alternative Name
Rozi, Siti Khalijah Mahmad
Rozi, S.K.M
Mahmad Rozi, S.K
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Scopus Author ID
57190815094

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Potential of Pretreated Spent Coffee Ground as Adsorbent for Oil Adsorption

2022-01-01 , Nasaruddin N.F.N. , Hairul Nazirah Abdul Halim , Siti Khalijah Mahmad Rozi , Zulfakar Mokhtar , Tan L.S. , Jusoh N.W.C.

Spent Coffee Ground (SCG) has the potential of becoming a low-cost adsorbent for oil removal. However, the effectiveness of SCG as an oil adsorbent is limited by its hydrophilicity. In this work, chemical pretreatment of SCG with acid and alkali was evaluated as a means of enhancing its performance for adsorbing palm cooking oil. The surface morphology of raw and pretreated SCG samples was characterised using a Scanning Electron Microscope (SEM). The functional groups were analysed using Fourier Transform Infrared (FTIR) spectroscopy. A comparison between adsorption performances was performed in terms of contact time in batch adsorption experiments to determine the adsorption capacity of SCG-based adsorbents with oil. The SEM results showed that more developed pores were present on the acid- and alkali-treated SCG samples compared to on the raw SCG sample, while the FTIR results indicated the elimination of hydrophilic cellulose and hemicellulose on these samples. According to these results, both acid- and alkali-treated SCG have better tendencies of adsorbing oil compared to raw SCG. The maximum oil adsorption capacity (2.549 g/g) occurred after 150 min of contact time between alkali-treated SCG adsorbents and oil.

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Amine functionalized carbon-based soybean curd residues (SCR) as potential adsorbent for carbon dioxide adsorption

2021-05-24 , Zakaria D.S. , Siti Khalijah Mahmad Rozi , Hairul Nazirah Abdul Halim , Mohamad S.

Currently, carbon dioxide (CO2) capture can preserve environmental quality by using carbon- based adsorbent. In this research, Polyethylenehexamine (PEHA) functionalized carbon-based soybean curd residues (carbonized SCR-PEHA) was prepared for CO2 adsorption. Analysis of functional groups of the prepared adsorbent using Fourier Transform Infrared Spectroscopy (FTIR), confirmed the functionalization of PEHA on the carbonized SCR. CO2 uptake of the carbonized SCR-PEHA was compared with the bare SCR using Thermogravimetric Analyzer (TGA) analysis. TGA results revealed that the adsorption capacity of CO2 for carbonized SCR-PEHA and bare SCR are 8.816 mg/g and 3.027 mg/g respectively. It was observed that functionalization of the PEHA on the surface of carbonized SCR had improved the adsorption capacity of CO2 by 2.92 times as compared to bare SCR. The phenomenon can be explained from the interaction of the CO2 with the available amine sites provided for the carbonized SCR-PEHA which significantly improved the CO2 adsorption. Hence, the carbonized SCR-PEHA demonstrate potential adsorbent for CO2.

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Performance of fatty acid-modified spent coffee grounds as a potential adsorbent for oil adsorption

2022-11-18 , Nasaruddin N.F.N. , Hairul Nazirah Abdul Halim , Siti Khalijah Mahmad Rozi , Zulfakar Mokhtar , Tan L.S. , Jusoh N.W.C.

Problems caused by fats, oils, and grease (FOG) in sewer systems have escalated over the years. FOG produced from households, restaurants, stalls, and food processing facilities have contaminated water resources through the sewer system. Thus, trace removal of oil from wastewater is a necessary measure to ensure minimal discharge of FOG into the environment. In the present study, due to the high volumes of coffee waste with no commercial value being generated daily, spent coffee grounds (SCG) were exploited as an oil adsorbent. However, due to their low hydrophobicity, SCG tend to have limited oil adsorption capacity. In this work, SCG underwent pre-treatment using alkali and were further modified with waste cooking oil (WCO) that contained free fatty acids (FFAs) at different ratios (1:10, 1:20, and 1:30) in order to enhance their oil adsorption performance. The performance of the synthesised adsorbents was tested in a batch adsorption process at different contact times. From the batch adsorption test, the highest oil adsorption capacity (2.807 ± 0.086?g/g) was observed using the 1:10 ratio of SCG to FFAs-WCO within 180?min of contact time.

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Application of Eggshell Membrane as an Adsorbent for Pollutants Removal; A Systematic Review

2023-09-01 , binti Abdul Tahrim N.S. , Siti Khalijah Mahmad Rozi , Mohd Yatim S.R. , Md Rashid R.I. , Haron N. , Ishak A.R.

Introduction: Introduction: The eggshell membrane (ESM) has gained attention for its utility as an adsorbent in various pollutant removal. Material & Methods: This study systematically reviewed 17 articles published from 2011 to 2021 that use ESM as adsorbent in the wastewater treatment. Result and Discussion: The review found that both modified and unmodified ESM-based adsorbents are promising for removing various types of contaminants. The pollutants targeted by the studies were heavy metals, dyes, and metalloids. Most of the research indicated that the ideal temperature for adsorption was at room temperature, and a lower pH range was favourable. More than 52% of the articles found that the Freundlich isotherm model best fits the adsorption data, indicating that the process is multilayer and heterogeneous. Conclusions: ESM-based adsorbents hold potential for pollutant removal. However, additional research is required to explore the applicability of these adsorbents for addressing different categories of contaminants.

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Novel palm fatty acid functionalized magnetite nanoparticles for magnetic solid-phase extraction of trace polycyclic aromatic hydrocarbons from environmental samples

2017-01-01 , Siti Khalijah Mahmad Rozi , Hamid Rashidi Nodeh , Muhammad Afzal Kamboh , Ninie Suhana Abdul Manan , Sharifah Mohamad

A novel adsorbent, palm fatty acid coated magnetic Fe3O4 nanoparticles (MNP-FA) was successfully synthesized with immobilization of the palm fatty acid onto the surface of MNPs. The successful synthesis of MNP-FA was further confirmed by X-Ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and Energy dispersive X-Ray spectroscopy (EDX) analyses and water contact angle (WCA) measurement. This newly synthesized MNP-FA was applied as magnetic solid phase extraction (MSPE) adsorbent for the enrichment of polycyclic aromatic hydrocarbons (PAHs), namely fluoranthene (FLT), pyrene (Pyr), chrysene (Cry) and benzo(a)pyrene (BaP) from environmental samples prior to High Performance Liquid Chromatography- Diode Array Detector (HPLC-DAD) analysis. The MSPE method was optimized by several parameters such as amount of sorbent, desorption solvent, volume of desorption solvent, extraction time, desorption time, pH and sample volume. Under the optimized conditions, MSPE method provided a low detection limit (LOD) for FLT, Pyr, Cry and BaP in the range of 0.01-0.05 ng mL–1. The PAHs recoveries of the spiked leachate samples ranged from 98.5% to 113.8% with the RSDs (n = 5) ranging from 3.5% to 12.2%, while for the spiked sludge samples, the recoveries ranged from 81.1% to 119.3% with the RSDs (n = 5) ranging from 3.1% to 13.6%. The recyclability study revealed that MNP-FA has excellent reusability up to five times. Chromatrographic analysis demonstrated the suitability of MNP-FA as MSPE adsorbent for the efficient extraction of PAHs from environmental samples.

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NOVEL MAGNETIC EGGSHELL MEMBRANE FUNCTIONALIZED WITH WASTE PALM FATTY ACID FOR SELECTIVE ADSORPTION OF OIL FROM AQUEOUS SOLUTION

2023-01-01 , Siti Khalijah Mahmad Rozi , Berhanundin K.M. , Ishak A.R. , Rasdi F.L.M. , Dom N.C. , Rahim N.Y. , Aziz M.Y. , Shafie F.A. , Abdullah A.M.

Emulsified oil in wastewater is a severe problem and requires extensive treatment before it can be disposed of in a manner that meets environmental regulation standards. One strategy to remove emulsified oil is by utilizing the adsorption process. The goal of this study is to synthesis magnetic eggshell membrane (ESM) functionalized with waste palm fatty acid, (MNP@ESM-WPFA) for the adsorption of oils (lubricating oil). The synthesis procedure involves three steps including preparation of ESM, functionalization of ESM with waste palm fatty acid (WPFA) and magnetization of eggshell membrane (ESM) functionalized with waste palm fatty acid (ESM-WPFA) through co-precipitation method to obtain MNP@ESM-WPFA. The novel adsorbent was characterized using SEM, FTIR, and EDX analyses. SEM analysis revealed the magnetic nanoparticles scattered throughout the porous and fibrous network structure of ESM-WPFA, confirming the successful synthesis of the MNP@ESM-WPFA. Further FTIR analysis on MNP@ESM-WPFA adsorbent revealed the appearance of peaks at 2933 cm-1 and 2852 cm-1 and 630 cm-1, thus confirming the presence of the alkyl chain of the waste palm fatty acid (WPFA) and Fe-O band on the surface of MNP@ESM-WPFA. The oil adsorption performance of MNP@ESM-WPFA was optimal at pH 7, treatment time of 50 minutes, and adsorbent dosage of 50 mg. The MNP@ESM-WPFA showed the highest oil adsorption capacity (K) for lubricating oil (4.61 mg/mg), followed by olive oil (2.72 mg/mg), and corn oil (2.00 mg/mg). The MNP@ESM-WPFA adsorbent was also reusable, with a sorption capacity that was maintained after five usage-regeneration cycles.

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Asam gelugur-based carbon aerogels for highly recyclable oils adsorption

2023-07 , Cheong Yi Xin , Siti Khalijah Mahmad Rozi , Monisha Devi Elan Solan , Syazwani Mahmad Puzi

Rapid development of the oil industries and improper oil management caused a huge amount of oil pollutant released into the water environment. Oil pollutant is toxic and may harm aquatic biodiversity. The present work highlights the facile preparation of carbon aerogels based from Asam Gelugur (CA@Ga) for oil remediation from aqueous. Analysis on the structure of CA@Ga using Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX) and Scanning Electron Microscopy (SEM), confirmed the successful preparation of CA@Ga through hydrothermal carbonization. The main parameters affecting the adsorption of oil such as the sorption time, pH and mass of sorbent were screened and oil adsorption studies revealed that the optimum conditions were at contact time of 3 minutes, pH of solution at 7 and the adsorbent mass of 2 g with the highest adsorption capacity of 0.82 + 0.01 g/g. CA@Ga displayed a good stability towards thermal treatment and exhibited good adsorption ability towards several types of oil. Recyclability study depicts that CA@Ga could be regenerated by simple physical treatments and retained a high sorption after 10 cycles with adsorption capacity of 0.80 + 0.01 g/g. Therefore, the prepared CA@Ga has potential in application of oil recovery and environmental protection.

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EFFECTIVE AND FAST ADSORPTIVE REMOVAL OF COOMASSIE BRILLIANT BLUE G 250 DYE FROM WATER USING Fe₃O₄ MAGNETIC NANOPARTICLES

2023-01-01 , Siti Khalijah Mahmad Rozi , Saufi N.A. , Rashidi N.A.N.M.

Coomassie Brilliant Blue G 250 (CBB G 250) is mainly generated from industrial textile effluent. Due to its non-degradable nature, it is not only environmentally hazardous, but also affect human health, causing irritations of the eye, respiratory or gastrointestinal tract. Therefore, a strategy for treating this colorant is necessary. This research highlights the synthesis of Fe3O4 Magnetic nanoparticles (Fe3O4 MNPs) as a low-cost adsorbent for removal of CBB G 250 dye from aqueous solutions. Fe3O4 MNPs were synthesized using chemical coprecipitation method. Characterization results revealed that the peaks at 537, 3400 and 1604 cm-1 in the Fourier Transform Infrared Spectroscopy spectrum represented the Fe-O band, O-H stretching and bending on the Fe3O4 MNPs surface, respectively. Crystal phase analysis indicated that Fe3O4 MNPs has a cubic spinel structure. Morphological analysis showed Fe3O4 MNPs are in nano-sized, spherical in shape, and have uniformly distributed particle size. The result from magnetic and surface area analyses demonstrated that Fe3O4 MNPs have 63.30 emu g-1 saturation magnetization and 123.5 m2 g-1 surface area. Thermal stability analysis showed that adsorbed water and hydroxyl group (6.25%) were lost at temperature below 100 ℃. At temperature between 260 ℃ and 540 ℃, approximately 2.09% weight loss were recorded due to change from magnetite (Fe3O4) to maghemite (Ɣ-Fe2O3) in crystal phase. Elemental analysis revealed that the Fe3O4 MNPs showed 24.50 % of Fe and 75.50 % of O. Following the confirmation of Fe3O4 MNPs structure, the impact of various parameters such as adsorbent dosage (0.02-0.14 g), contact time (5-20 minutes), initial concentration (25-100 ppm) and pH (3-10) on the adsorption of CBB G 250 dyes were investigated. Experimental results showed that Fe3O4 MNPs achieved 95% removal of CBB G 250 at optimum conditions of 0.12 g dosage, 15 minutes contact time, 50 ppm initial dye concentration and at pH value of 8. Adsorption isotherms and kinetics revealed that the adsorption process using Fe3O4 MNPs in this study obeys both Langmuir and Freundlich isotherm and pseudo-second-order kinetic. The results obtained from this study confirmed that Fe3O4 MNPs can be used as an adsorbent material for the removal of dye from effluent.

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An integrated DFT calculation and adsorption study of desiccated coconut waste-based biochar in CO2 environment

2024-01-01 , Rafizah Rahamathullah , Zakaria D.S. , Siti Khalijah Mahmad Rozi , Hairul Nazirah Abdul Halim , Razak F.I.A. , Sapari S.

Abstract: This study presents a new series of amine-functionalized biochar derived from desiccated coconut waste (amine-biochar@DCW) as potential CO2 adsorbents. The CO2 adsorption experiment revealed that TETA-biochar@DCW had the highest adsorption capacity of 61.78 mg/g. Prior to the experimental studies, Density Functional Theory (DFT) was conducted at B3LYP/6-31G (d,p) to evaluate the energy band gap, global chemical reactivity descriptors (GCRD), and molecular electrostatic potentials (MEP) to compare the experimental findings. The results from the simulated data indicate that TETA-biochar@DCW has the lowest HOMO–LUMO gap at 2.7890 eV before adsorption, and it increases after CO2 adsorption occurs. The 3D plots from MEP also show that TETA-biochar@DCW is a reactive adsorbent for CO2 gases. Overall, the theoretical and experimental results of the amine-biochar@DCW suggest its potential as a promising and cost-effective adsorbent for CO2 capture. Highlights: • Newly prepared amine-biochar@DCW was assessed as CO2 adsorbents. • TETA-biochar@DCW presents the highest CO2 capture capacity. • TETA substituents significantly reduce the HOMO-LUMO gap values. • 3D MEP plots confirm the adsorption ability of TETA-biochar@DCW towards CO2 gases. Graphical Abstract: [Figure not available: see fulltext.]

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Asam Gelugur-based carbon aerogels for highly recyclable oils adsorption

2023-07 , Cheong Yi Xin , Siti Khalijah Mahmad Rozi , Monisha Devi Elan Solan , Syazwani Mahmad Puzi

Rapid development of the oil industries and improper oil management causeda huge amount of oil pollutant released into the water environment. Oil pollutant is toxic and may harm aquatic biodiversity. The present work highlights the facile preparation of carbon aerogels basedfromAsam Gelugur (CA@Ga) for oil remediation from aqueous. Analysis on the structure of CA@Gausing Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX) and Scanning Electron Microscopy (SEM), confirmed the successful preparation of CA@Ga through hydrothermal carbonization. The main parameters affecting the adsorption of oil such as the sorption time, pH and mass of sorbent were screened and oil adsorption studies revealed that the optimum conditions were at contact time of 3 minutes, pH of solution at 7 and the adsorbent mass of 2 g with the highest adsorption capacity of 0.82 +0.01 g/g.CA@Ga displayed a good stability towards thermal treatment and exhibited good adsorption ability towards several types of oil. Recyclability study depicts that CA@Ga could be regenerated by simple physical treatments and retaineda high sorption after 10 cycles with adsorption capacity of 0.80 +0.01 g/g. Therefore, the prepared CA@Ga has potential in application of oil recovery and environmental protection.

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