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Application of immersed MF (IMF) followed by reverse osmosis (RO) membrane for wastewater reclamation: A case study in Malaysia

Ujang Z, Ng KS, Tg Hamzah TH, Roger P, Ismail MR, Shahabudin SM, et al.

Water Sci Technol, 2007;56(9):103-8.
PMID: 18025737

A pilot scale membrane plant was constructed and monitored in Shah Alam, Malaysia for municipal wastewater reclamation for industrial application purposes. The aim of this study was to verify its suitability under the local conditions and environmental constraints for secondary wastewater reclamation. Immersed-type crossflow microfiltration (IMF) was selected as the pretreatment step before reverse osmosis filtration. Secondary wastewater after chlorine contact tank was selected as feed water. The results indicated that the membrane system is capable of producing a filtrate meeting the requirements of both WHO drinking water standards and Malaysian Effluent Standard A. With the application of an automatic backwash process, IMF performed well in hydraulic performance with low fouling rate being achieved. The investigations showed also that chemical cleaning is still needed because of some irreversible fouling by microorganisms always remains. RO treatment with IMF pretreatment process was significantly applicable for wastewater reuse purposes and promised good hydraulic performance.
Drying kinetics and stabilization of sewage sludge in lagoon in hot climate

Idris A, Yen OB, Hamid MH, Baki AM

Water Sci Technol, 2002;46(9):279-86.
PMID: 12448479

A sludge lagoon has been adopted as a simple and cost effective method for dewatering of sludge. The processes occurring in a sludge lagoon include thickening, dewatering, storage and stabilization; all happening simultaneously. The objective of this study is to determine the dewatering and drying rates at pilot-scale which occur in a lagoon having different design configurations. Two types of sludge lagoons with different initial sludge depth (0.75 m and 0.375 m) were investigated to measure the drying behavior and drying efficiency. The first design is a sludge lagoon with a clay bottom where the dewatering mechanisms are decanting supernatant and evaporation. The second design is a sludge lagoon installed with a sand and underdrains system, where the dewatering mechanisms are filtration or draining and evaporation. Sludge drying kinetic models with high fitness were plotted to describe the sludge drying behavior. Drying of sludge in a sludge lagoon with a clay bottom can best be described by an exponential function. Whereas, drying of sludge in a sludge lagoon with sand and underdrains system followed a logarithmic function. A lagoon designed with sand and underdrains system and having shallower sludge depth was the most efficient. The reduction in volatile solids was lower than 4% during the study period. The drying process proceeded with an increase in dryness and decline in pH value.
Fulltext Immunological Analysis of the Hepatitis B Virus "a" Determinant Displayed on Chimeric Virus-Like Particles of Macrobrachium rosenbergii Nodavirus Capsid Protein Produced in Sf9 Cells

Ninyio NN, Ho KL, Ong HK, Yong CY, Chee HY, Hamid M, et al.

Vaccines (Basel), 2020 Jun 04;8(2).
PMID: 32512923 DOI: 10.3390/vaccines8020275

Chimeric virus-like particles (VLPs) have been widely exploited for various purposes including their use as vaccine candidates, particularly due to their ability to induce stronger immune responses than VLPs consisting of single viral proteins. In the present study, VLPs of the Macrobrachium rosenbergii nodavirus (MrNV) capsid protein (Nc) displaying the hepatitis B virus "a" determinant (aD) were produced in Spodoptera frugiperda (Sf9) insect cells. BALB/c mice immunised with the purified chimeric Nc-aD VLPs elicited a sustained titre of anti-aD antibody, which was significantly higher than that elicited by a commercially available hepatitis B vaccine and Escherichia coli-produced Nc-aD VLPs. Immunophenotyping showed that the Sf9-produced Nc-aD VLPs induced proliferation of cytotoxic T-lymphocytes and NK1.1 natural killer cells. Furthermore, enzyme-linked immunospot (ELISPOT)analysis showed the presence of antibody-secreting memory B cells in the mice splenocytes stimulated with the synthetic aD peptide. The significant humoral, natural killer cell and memory B cell immune responses induced by the Sf9-produced Nc-aD VLPs suggest that they present good prospects for use as a hepatitis B vaccine candidate.
Genetic diversity of secreted protein with an altered thrombospondin repeat (SPATR) of Plasmodium knowlesi clinical isolates from Malaysia

Azlan UW, Lau YL, Hamid MHA, Jelip J, Ooi CH, Mudin RN, et al.

Trop Biomed, 2022 Dec 01;39(4):504-510.
PMID: 36602208 DOI: 10.47665/tb.39.4.006

The Plasmodium knowlesi secreted protein with an altered thrombospondin repeat (PkSPATR) is an important protein that helps in the parasite's invasion into the host cell. This protein has been regarded as one of the potential vaccine candidates against P. knowlesi infection. This study investigates the genetic diversity and natural selection of PkSPATR gene of P. knowlesi clinical isolates from Malaysia. PCR amplification of the full length PkSPATR gene was performed on 60 blood samples of infected P. knowlesi patients from Peninsular Malaysia and Malaysian Borneo. The amplified PCR products were cloned and sequenced. Sequence analysis of PkSPATR from Malaysia showed higher nucleotide diversity (CDS p: 0.01462) than previously reported Plasmodium vivax PvSPATR (p = 0.0003). PkSPATR from Peninsular Malaysia was observed to have slightly higher diversity (CDS p: 0.01307) than those from Malaysian Borneo (CDS p: 0.01212). Natural selection analysis on PkSPATR indicated significant purifying selection. Multiple amino acid sequence alignment revealed 69 polymorphic sites. The phylogenetic tree and haplotype network did not show any distinct clustering of PkSPATR. The low genetic diversity level, natural selection and absence of clustering implied functional constrains of the PkSPATR protein.
Knowledge of blood-borne infectious diseases and the practice of universal precautions amongst health-care workers in a tertiary hospital in Malaysia

Hamid MZ, Aziz NA, Anita AR, Norlijah O

Southeast Asian J. Trop. Med. Public Health, 2010 Sep;41(5):1192-9.
PMID: 21073041

This study aimed to assess the knowledge of blood-borne diseases transmitted through needle stick injuries amongst health-care workers in a tertiary teaching hospital. We also aimed to assess the practices of universal precautions amongst these workers and its correlation with the facts. We carried out a cross-sectional study from January to July 2008 involving various levels of health-care workers in Serdang Hospital, Selangor, Malaysia. A self-administered questionnaire assessing knowledge of blood-borne diseases and universal precautions, and actual practice of universal precautions was used. Two hundred fifteen respondents participated in this study; 63.3% were staff nurses. The mean knowledge score was 31.84 (SD 4.30) and the mean universal practice score was 9.0 (SD 2.1). There was a small, positive correlation between knowledge and actual practice of universal precautions (r = 0.300, n = 206, p < 0.001) amongst the cohort studied. Factors such as age and years of experience did not contribute towards acquisition of knowledge about blood-borne illnesses or the practice of universal precautions.
Clinical features and risk factors for HIV encephalopathy in children

Hamid MZ, Aziz NA, Zulkifli ZS, Norlijah O, Azhar RK

Southeast Asian J. Trop. Med. Public Health, 2008 Mar;39(2):266-72.
PMID: 18564712

A prospective cohort study was conducted to determine the incidence of progressive encephalopathy (PE) and its associated clinical manifestations amongst a cohort of HIV infected children attending the HIV/AIDS clinic of the Pediatric Institute, Kuala Lumpur Hospital, Malaysia. Neurological and neurobehavioral assessments were performed in 55 children with HIV over a 24-month study period. Parameters assessed were physical and neurological assessments, CD4 counts, CD4 percentages, RNA viral loads and an IQ assessment at four monthly intervals. PE was diagnosed when patient developed at least one of the definitive criteria for PE based on the Consensus of Pediatric Neurology/Psychology Working Group, AIDS Clinical Trial 1996. The incidence of encephalopathy was 18.2% (n = 10) in 2002. All the patients had hepatosplenomegaly, lymphadenopathy, abnormal deep tendon reflexes and five had impairment in brain growth. The CD4 counts and CD4 percentages were more likely to be associated with PE compared to the non-PE group.
Fulltext Patient registries supplement. Foreword

Abdul Hamid M

Med J Malaysia, 2008 Sep;63 Suppl C:vii.
PMID: 19227668
Fulltext Skills amongst parents of children with asthma: a pilot interventional study in primary care setting

Aziz NA, Norzila MZ, Hamid MZ, Noorlaili MT

Med J Malaysia, 2006 Dec;61(5):534-9.
PMID: 17623952 MyJurnal

The increasing prevalence of childhood asthma has become a concern among health practitioners. Effective management emphasizes long-term management and inhaled therapy has become the mainstay home management for children. However, proper utilization of medication is pertinent in improving control. Proper asthma education is mandatory in improving skills and confidence amongst parents. To assess the skills of using the metered-dose inhaler (MDI) with a spacer among asthmatic children before and after educational intervention and to analyse any difficulties which may occur amongst the participants in executing the assessment steps. A cross-sectional clinic based study involving 85 parents and children with asthma. A standardized metered-dose inhaler-spacer checklist of eight steps of medication usage and five steps of cleaning the spacer were used as the assessment tools for pre and post intervention. The performance on using the inhaler-spacer and spacer cleaning knowledge pre and two months post intervention was evaluated. One point was given for each correct step and zero points for incorrect answers/steps. The mean score for skills of inhaler technique improved significantly after educational intervention (3.51 to 6.01, p < 0.0001) as did the mean score for parental knowledge of spacer cleaning technique (1.35 to 3.16, p 0.001). Analysis showed only a limited improvement even after an educational session in three steps of inhalation technique: step 5 (23.5%/69.4%), step 6 (28.2%/68.2%) and step 7 (25.9%/61.2%). Parents with asthmatic children had poor skills in utilizing their children's medication. A short-term educational intervention was able to improve overall knowledge and skill but certain skills need more emphasizing and training.
Study site: Klink HUKM Taman Jaya, Cheras, Kuala Lumpur, Malaysia (primary care clinic for Hospital University Kebangsaan Malaysia)
DNA damage evaluation of hydroxyapatite on fibroblast cell L929 using the single cell gel electrophoresis assay

Rajab NF, Yaakob TA, Ong BY, Hamid M, Ali AM, Annuar BO, et al.

Med J Malaysia, 2004 May;59 Suppl B:170-1.
PMID: 15468872

Hydroxyapatite is the main component of the bone which is a potential biomaterial substance that can be applied in orthopaedics. In this study, the biocompatibility of this biomaterial was assessed using an in vitro technique. The cytotoxicity and genotoxicity effect of HA2 and HA3 against L929 fibroblast cell was evaluated using the MTT Assay and Alkaline Comet Assay respectively. Both HA2 and HA3 compound showed low cytotoxicity effect as determined using MTT Assay. Cells viability following 72 hours incubation at maximum concentration of both HA2 and HA3 (200 mg/ml) were 75.3 +/- 8.8% and 86.7 +/- 13.1% respectively. However, the cytotoxicity effect of ZnSO4.7H2O as a positive control showed an IC50 values of 46 mg/ml (160 microM). On the other hand, both HA2 and HA3 compound showed a slight genotoxicity effect as determined using the Alkaline Comet Assay following incubation at the concentration 200 mg/ml for 72 hours. This assay has been widely used in genetic toxicology to detect DNA strand breaks and alkali-labile site. The percentage of the cells with DNA damage for both substance was 27.7 +/- 1.3% and 15.6 +/- 1.0% for HA2 and HA3 respectively. Incubation of the cells for 24 hours with 38 microg/ml (IC25) of positive control showed an increase in percentage of cells with DNA damage (67.5 +/- 0.7%). In conclusion, our study indicated that both hydroxyapatite compounds showed a good biocompatibility in fibroblast cells.
Causes of mortality in patients with psoriasis in Malaysia - Evidence from the Malaysian Psoriasis Registry

Kwan Z, Yeoh CA, Mohd Affandi A, Alias FA, Hamid M, Baharum N, et al.

Med J Malaysia, 2015 Oct;70(5):273-7.
PMID: 26556114

BACKGROUND: Patients with severe psoriasis, namely those requiring phototherapy or systemic treatment, have an increased risk of death. The aim of this study was to determine the prevalence, aetiology and risk factors for mortality among adult patients aged 18 years and above with psoriasis in Malaysia.

METHODS: This was a retrospective study involving adult patients notified by dermatologists to the Malaysian Psoriasis Registry between July 2007 and December 2013. Data were cross-checked against the National Death Registry. Patients certified dead were identified and the cause of death was analysed. Multivariate analysis using multiple logistic regression were conducted on potential factors associated with higher risk of mortality.

RESULTS: A total of 419 deaths were identified among the 9775 patients notified. There were four significant risk factors for higher mortality: age>40 years (age 41-60 years old, Odds Ratio (OR) 2.70, 95%CI 1.75, 4.18; age>60 years OR 7.46, 95%CI 4.62, 12.02), male gender (OR 1.72, 95%CI 1.33,2.22), severe psoriasis with body surface area (BSA) >10% (OR 1.52, 95%CI 1.19, 1.96) and presence of at least one cardiovascular co-morbidity (OR 1.67, 95% CI 1.30, 2.14). Among the 301 patients with verifiable causes of death, the leading causes were infection (33.9%), cardiovascular disease (33.6%) and malignancy (15.9%).

CONCLUSION: Infection was the leading cause of death among psoriasis patients in Malaysia. Although cardiovascular diseases are well-known to cause significant morbidity and mortality among psoriasis patients, the role of infections and malignancy should not be overlooked.
Fulltext Acute glomerulonephritis in Kelantan--a prospective study

D'Cruz F, Samsudin AT, Hamid MS, Abraham T

Med J Malaysia, 1990 Jun;45(2):123-30.
PMID: 2152016

A prospective study of acute nephritis in children was conducted at the Universiti Sains Malaysia Hospital, Kubang Kerian between July 1987 and June 1988. One hundred and twenty four children were admitted with acute glomerulonephritis. The aim of the study was to determine the clinical pattern of the nephritis as well as its aetiology. The majority of our patients came from the lower socio-economic group and 54% of the families had incomes below the poverty line. Preceding skin infection was much more common than throat infection. The children showed a high incidence of complications: severe hypertension (43.6%), hypertensive encephalopathy (11.3%), clinical pulmonary oedema (36.3%), severe azotaemia (10.5%), and prolonged gross haematuria (13.7%). By using immunologic indices such as ASOT, anti-DNase B and complement 3, it was concluded that 121 of the 124 patients had post-streptococcal nephritis.
Myofibroblastoma of the breast

Shanmugasiva VV, Ramli Hamid MT, Fadzli F, Shaleen Kaur KS, Abd Rahman N, Rahmat K

Malays J Pathol, 2018 Dec;40(3):349-353.
PMID: 30580368

INTRODUCTION: Myofibroblastoma is a rare benign mesenchymal tumour arising from the stromal elements of the breast tissue. Histopathological variants such as classic, cellular, collagenous / fibrous, lipomatous, infiltrative, myxoid and epithelioid have been identified. Most myofibroblastomas are immunoreactive for CD34, actin, CD10 and desmin, usually express oestrogen receptor (ER), progesterone receptor (PR) and variably express androgen receptor (AR).
CASE REPORT: We report a case of myofibroblastoma in an octogenarian male presenting with painless solitary breast lump. Mammography (digital tomosynthesis) and ultrasound showed a well-circumscribed hyperdense mass and hypoechoic, solid, oval mass with peripheral vascularity respectively. Patient underwent wide local excision.
DISCUSSION: Diverse characteristics of myofibroblastoma on imaging necessitates histopathological analysis for an accurate diagnosis. Myofibroblastoma are often confused with fibroadenomas due to the benign imaging characteristics and with malignant neoplasia due to their wide morphological spectrum. Surgical excision is considered curative.
Primary anorectal malignant melanoma: A clinical, radiology and pathology correlation

Bohan S, Ramli Hamid MT, Poh KS, Chow TK, Chan WY

Malays J Pathol, 2020 Dec;42(3):461-467.
PMID: 33361730

INTRODUCTION: Primary gastrointestinal melanomas are mucosal malignancies that arise from melanocytes in the oropharynx, rectum, and anus. Anorectal malignant melanoma (ARMM) are exceedingly rare, accounting for less than 1% of all melanomas, 0.1% of all rectal malignancies and 4% of anal malignancies. Diagnosis is frequently delayed as these lesions are often mistaken for haemorrhoids. Histological evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Due to the aggressive nature, 61% of patients with ARMM would already have lymph node involvement or distant metastases, by the time of diagnosis. Prognosis is usually poor with 5-year survival rate of <20%. We report a case of metastatic ARMM in an elderly lady who presented with symptoms and signs mimicking a haemorrhoid.
CASE REPORT: A 69-year-old lady presented with one year history of intermittent rectal bleed and an anorectal mass that was initially treated as haemorrhoid. Colonoscopy showed a hyperpigmented mass in the anorectal region which was confirmed as malignant melanoma on histopathological examination. Imaging with CT and MRI demonstrated locally advanced tumour with distant metastases to the liver and lung. Patient was referred for palliative management.
CONCLUSION: ARMM is a rare malignancy and often presented with non-specific clinical signs. Diagnosis is frequently delayed without high index of suspicion. MRI pelvis is the imaging of choice to assess local extent of disease. Histologic evaluation with special immunohistochemical stains is often necessary for definitive diagnosis. Prognosis is poor despite surgical and chemotherapeutic interventions.
Encephalitis and retarded growth of chicks caused by Sitiawan virus, a new isolate belonging to the genus Flavivirus

Kono Y, Tsukamoto K, Abd Hamid M, Darus A, Lian TC, Sam LS, et al.

Am J Trop Med Hyg, 2001 5 19;63(1-2):94-101.
PMID: 11358004

A new virus named Sitiawan virus (SV) was isolated from sick broiler chicks in chicken embryos. The virus replicated well with cytopathogenic effect (CPE) in the chicken B-lymphocyte cell line LSCC-BK3. The virus was an enveloped RNA virus of approximately 41 nm in size with hemagglutinating activity (HA) to goose erythrocytes. It was cross-reactive with Japanese encephalitis virus (JEV), a member of flaviviruses by HA inhibition tests but not by cross-virus neutralization tests. The cDNA fragment of NS5 gene was amplified with primers corresponding to NS5 gene of flaviviruses. The nucleotide sequences were 92% homologous to Tembusu virus, a member of the mosquito-borne virus cluster of the genus Flavivirus. In cross-neutralization tests with Tembusu virus, antiserum to SV did not neutralize Tembusu virus, and antiserum to Tembusu virus neutralized more weakly to SV than against homologous virus. These results indicate that SV is a new virus which can be differentiated serologically from Tembusu virus but is otherwise similar with respect to nucleotide sequence. The virus causes encephalitis, growth retardation, and increased blood glucose levels in inoculated chicks.
Lateral Flow Recombinase Polymerase Amplification Assays for the Detection of Human Plasmodium Species

Lai MY, Abdul Hamid M, Jelip J, Mudin RN, Lau YL

Am J Trop Med Hyg, 2023 Mar 13.
PMID: 36913921 DOI: 10.4269/ajtmh.22-0657

This study highlights the development of two lateral flow recombinase polymerase amplification assays for the diagnosis of human malaria. The lateral flow cassettes contained test lines that captured biotin-, 6-carboxyfluorescein, digoxigenin-, cyanine 5-, and dinitrophenyl-labeled amplicons. The overall process can be completed in 30 minutes. Recombinase polymerase amplification coupled with lateral flow had a detection limit of 1 copy/µL for Plasmodium knowlesi, Plasmodium vivax, and Plasmodium falciparum. No cross-reactivity was observed among nonhuman malaria parasites such as Plasmodium coatneyi, Plasmodium cynomolgi, Plasmodium brasilanium, Plasmodium inui, Plasmodium fragile, Toxoplasma gondii, Sarcocystis spp., Brugia spp., and 20 healthy donors. It is rapid, highly sensitive, robust, and easy to use. The result can be read without the need for special equipment and thus has the potential to serve as an effective alternative to polymerase chain reaction methods for the diagnosis of malaria.
Fulltext Thermodynamic stability, in-vitro permeability, and in-silico molecular modeling of the optimal Elaeis guineensis leaves extract water-in-oil nanoemulsion

Romes NB, Abdul Wahab R, Abdul Hamid M, Oyewusi HA, Huda N, Kobun R

Sci Rep, 2021 10 21;11(1):20851.
PMID: 34675286 DOI: 10.1038/s41598-021-00409-0

Nanoemulsion is a delivery system used to enhance bioavailability of plant-based compounds across the stratum corneum. Elaeis guineensis leaves are rich source of polyphenolic antioxidants, viz. gallic acid and catechin. The optimal E. guineensis leaves extract water-in-oil nanoemulsion was stable against coalescence, but it was under significant influence of Ostwald ripening over 90 days at 25 °C. The in-vitro permeability revealed a controlled and sustained release of the total phenolic compounds (TPC) of EgLE with a cumulative amount of 1935.0 ± 45.7 µgcm-2 after 8 h. The steady-state flux and permeation coefficient values were 241.9 ± 5.7 µgcm-2 h-1 and 1.15 ± 0.03 cm.h-1, respectively. The kinetic release mechanism for TPC of EgLE was best described by the Korsmeyer-Peppas model due to the highest linearity of R2 = 0.9961, indicating super case II transport mechanism. The in-silico molecular modelling predicted that the aquaporin-3 protein in the stratum corneum bonded preferably to catechin over gallic acid through hydrogen bonds due to the lowest binding energies of - 57.514 kcal/mol and - 8.553 kcal/mol, respectively. Thus, the in-silico study further verified that catechin could improve skin hydration. Therefore, the optimal nanoemulsion could be used topically as moisturizer to enhance skin hydration based on the in-silico prediction.
Fulltext Design and Development of an Ergonomic Trolley-Lifter for Sheet Metal Handling Task: A Preliminary Study

Radin Umar RZ, Ahmad N, Halim I, Lee PY, Hamid M

Saf Health Work, 2019 Sep;10(3):327-335.
PMID: 31497329 DOI: 10.1016/j.shaw.2019.06.006

BACKGROUND: There have been some concerns related to manual handling of large items in industry. Manual handling operations of large sheet metal may expose workers to risks related to efficiency as well as occupational safety and health. Large sheet metals are difficult to move and burdensome to lift/transfer, and handling the sharp sheet edges may result in contact stress and/or cut injuries on the workers.
METHODS: Through observation, interview, and immersive simulation activities, a few problems related to current handling of sheet metals were identified. A sheet metal trolley-lifter was then designed and fabricated to address these issues. A pilot study on the use of the developed trolley-lifter for handling sheet metals was conducted to compare between the new and traditional handling methods.
RESULTS: The pilot study of the trolley-lifter showed promising results in terms of improving the cycle time, manpower utilization, and working postures compared with the traditional handling method.
CONCLUSION: The trolley-lifter offers an alternative solution to automation and a mechanized assistive device by providing a simple mechanism to assist the handling of sheet metals effectively and safely.
Fulltext Pleural anthracosis presenting with massive effusion: a rare entity

Amiseno R, Ban AY, Masir N, Hamidi LR, Faisal Abdul Hamid M

Respirol Case Rep, 2019 Feb;7(2):e00390.
PMID: 30519469 DOI: 10.1002/rcr2.390

Pleural anthracosis is rare and, in most cases, is diagnosed incidentally or at autopsy. We report a 67-year-old man with pleural anthracosis. He was initially referred for possible tuberculous pleural effusion and had recurrent admissions for symptomatic pleural effusion, which increased with each subsequent episode. A thoracoscopic examination demonstrated diffuse hyperpigmentation in both parietal and visceral pleura. Parietal pleural biopsy indicated granuloma with foreign body giant cell. A contrast-enhanced computed tomography (CECT) thorax showed focal plaques in parietal pleura with calcifications in the ipsilateral lung. Investigations for tuberculosis, fungal, and malignancy proved to be negative. With these results, a diagnosis of pleural anthracosis was made. This case highlights the unusual presentation of pleural anthracosis with pleural effusion.
Implantation of GLP-1 secreting cells fails to recapitulate effects of exogenous GLP-1 mimetics in mice

Vasu S, Hamid MH, McCluskey JT, Irwin N, Flatt PR

Regul. Pept., 2010 Sep 9;164(1):32.
PMID: 26009405 DOI: 10.1016/j.regpep.2010.07.075
Fulltext Profitable Fischer Tropsch realization via CO2-CH4 reforming; an overview of nickel-promoter-support interactions

Alhassan M, Jalil AA, Bahari MB, Owgi AHK, Nabgan W, Hassan NS, et al.

RSC Adv, 2023 Jan 06;13(3):1711-1726.
PMID: 36712622 DOI: 10.1039/d2ra06773k

Environmental pollution, climate change, and fossil fuel extinction have aroused serious global interest in the search for alternative energy sources. The dry reforming of methane (DRM) could be a good technique to harness syngas, a starting material for the FT energy process from greenhouse gases. Noble metal DRM catalysts are effective for the syngas generation but costly. Therefore, they inevitably, must be replaced by their Ni-based contemporaries for economic reasons. However, coking remains a strong challenge that impedes the industrialization of the FT process. This article explains the secondary reactions that lead to the production of detrimental graphitic coke deposition on the surface of active nickel catalyst. The influence of nickel particle size, impact of extra surface oxygen species, interaction of Ni catalysts with metal oxide supports/promoters, and larger fraction of exposed nickel active sites were addressed in this review. Size of active metal determines the conversion, surface area, metal dispersion, surface reactions, interior diffusion effects, activity, and yield. The influence of oxygen vacancy and coke deposition on highly reported metal oxide supports/promoters (Al2O3, MgO and La2O3) was postulated after studying CIFs (crystallographic information files) obtained from the Crystallography open database (COD) on VESTA software. Thus, overcoming excessive coking by La2O3 promotion is strongly advised in light of the orientation of the crystal lattice characteristics and the metal-support interaction can be used to enhance activity and stability in hydrogen reforming systems.

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