Hambali Umar Hambali
@unilorin.edu.ng
Lecturer, Faculty of Engineering and Technology
University of Ilorin
RESEARCH, TEACHING, or OTHER INTERESTS
General Chemical Engineering, Catalysis, Renewable Energy, Sustainability and the Environment, Filtration and Separation
Scopus Publications
Scopus Publications
Oluwatoyin Rhoda Ayanwusi, Sulyman A. Abdulkareem, Taiwo Temitayo Michael, Kingsley O. Iwuozor, Ebuka Chizitere Emenike, Hambali Umar Hambali, and Adewale George Adeniyi
Wiley
AbstractBiochar, a solid material derived from a thermochemical process, has received significant attention due to its usefulness in various sectors. Previous studies have been conducted to improve the properties and quality of this material by altering the thermochemical processes, treating the feedstock, hybridizing the feedstock, and so forth, but little has been done on the effect of varying the reactor's configuration. This research aims to study the effect of varying the stainless‐steel‐based combustion compartment volume of a biomass‐fueled top‐lit updraft gasifier on the groundnut shell biochar. The biochar yields for reactors ranged from 34.9% to 51.2%. The sample produced in the smallest combustion compartment volume showed the highest carbon content, according to energy dispersive X‐ray spectroscopy (EDX) analysis. Potassium, another major element, decreased as the combustion compartment was reduced. Scanning electron microscopy (SEM) analysis revealed that the biochar samples produced had an irregular shape and rough surfaces, and reducing the combustion compartment volume resulted in larger particles on the surface. Fourier transform infrared (FTIR) spectroscopy analysis showed similarities and differences in peaks observed for all the samples. The biochar samples produced can find applications in wastewater treatment, energy conversion and storage, and soil amendment, and the findings contribute to the design and optimization of biomass‐based gasifiers.
H. U. Hambali, T. Jimoh, T. L. Peng, A. A. Umar, B. T. Mutiullah, and J. A. Okolie
African Journals Online (AJOL)
Indubitably, the combustion of fossils fuels has really hampered the preservation of the environment as it raises the content of CO2 in the atmosphere which consequentially results in global warming. Adsorption process remains the popular technique owing to its cost-effectiveness, faster reaction rates and flexible design. This review detailed the research progress in preparation of modified zeolite-based and novel adsorbents towards enhanced CO2 capture. In addition, the review presents an overview on available techniques of capturing CO2 and mechanism of reaction. Large surface area, distinctive mechanical characteristics and uniform dispersion of the exchangeable cations in the porous framework is prerequisite for high adsorption capacity and stability over zeolite materials. Novel nanostructured and polymeric zeolite composite materials seem promising because they offer solutions to energy-related problems while also contributing to environmental preservation. It is anticipated that this review could offer a conclusive roadmap in the pursuit of a cost-effective, industrially potent adsorbent suited for enhance CO2 capture.
Mansur Alhassan, Aishah Abdul Jalil, Mahadi Bin Bahari, Hambali Umar Hambali, Thuan Van Tran, Sharif H. Zein, and Saravanan Rajendran
Elsevier BV
I. A. Mohammed, S. I. Mustapha, F. A. Aderibigbe, H. U. Hambali, A. M. Afolabi, K. B. Muritala, and U. M. Aliyu
African Journals Online (AJOL)
As an alternative to the physical storage of hydrogen as compressed gas or liquid hydrogen requiring high-pressure tanks and cryogenic temperatures, the material-based storage of hydrogen in solids involves hydrogen uptake and release from the surface of adsorbents or within interstitials of hydrides. We report a hydrothermic reduction of rutile-ilmenite mineral into hydrogen-rich fibrous products, η-Ti2FeO0.2H2.8, in an ethanol-water system at 120°C for 4 hrs. As part of a project to generate hydrogen from water-ethanol system using advanced catalysts containing graphene oxide (GO) as carbon source, a system of 62.5 μg graphene oxide per g of rutile-ilmenite mineral was employed in a concentration of 50 mg/mL of ethanol-water solution. As well as in the original mineral, XRD of thermal annealed mineral between 500 and 800°C showed no hydride or phase change in rutile-ilmenite. With hydrothermal treatment of GO/rutile-ilmenite (50 mg/mL) in ethanol-water (1:1 v/v) at 120°C, a hydrogen-rich ferrotitanium hydride phase was formed, and there was a change in morphology from plate-like and granular particles into fibrous structures. Like the release of hydrogen by its ‘carriers’ (e.g., CaH2, NH4BH4, NaBH4, NH3, formic acid), it is anticipated that hydrogen was generated from the ethanol-water system in-situ, which reduced the rutile-ilmenite mineral into a hydride. EDX results showed that the reduction affected specifically the oxides of Fe and aluminosilicates in the mineral. The study demonstrated a possibility of in-situ hydrogen generation and storage via low-temperature graphene oxide hydrothermic reduction of rutile-ilmenite mineral in an ethanol-water system.
Tajudeen A. Oyehan, Babatunde Abiodun Salami, Abdulrahman A. Abdulrasheed, Hambali Umar Hambali, Afeez Gbadamosi, Eugenia Valsami-Jones, and Tawfik A. Saleh
Elsevier BV
N.S. Hassan, A.A. Jalil, L.Y. Twu, N.A.A. Fatah, H.U. Hambali, I. Hussain, and M.L. Firmansyah
Elsevier BV
A.H.K. Owgi, A.A. Jalil, M.A.A. Aziz, M. Alhassan, H.U. Hambali, W. Nabgan, R. Saravanan, and A.H. Hatta
Elsevier BV
Abdulwasiu Muhammed Raji, Hambali Umar Hambali, Zahid Iqbal Khan, Zurina Binti Mohamad, Hassan Azman, and Raphael Ogabi
SAGE Publications
Owing to the superior thermal insulating attributes of rigid polyurethane foam (RPUF) compared to other insulating materials (expanded and extruded polystyrene, mineral wool), it remains the most dominant insulating material and most studied polymer foam. Like other polyurethane foam, RPUF is highly flammable, necessitating the incorporation of flame retardants (FR) during production to lower combustibility, promoting its continuous use as insulation material in construction, transportation, and others. The popular approaches for correcting the high flammability of RPUF are copolymerization and blending (with FR). The second method has proven to be most effective as there are limited trade-offs in RPUF properties. Meanwhile, the high flammability of RPUF is still a significant hindrance in emerging applications (sensors, space travel, and others), and this has continuously inspired research in the flame retardancy of RPUF. In this study, properties, and preparation methods of RPUF are described, factors responsible for the high flammability of PUF are discussed, and flame retardancy of RPUF is thoroughly reviewed. Notably, most FR for RPUF are inorganic nanoparticles, lignin, intumescent FR systems of expandable graphite (EG), ammonium polyphosphate (APP), and hybridized APP or EG with other FR. These could be due to their ease of processing, low cost, and being environmentally benign. Elaborate discussion on RPUF FR mechanisms were also highlighted. Lastly, a summary and future perspectives in fireproofing RPUF are provided, which could inspire the design of new FR for RPUF.
Bemgba B. Nyakuma, Syie L. Wong, Olagoke Oladokun, Aliyu A. Bello, Hambali U. Hambali, Tuan Amran T. Abdullah, and Keng Y. Wong
Springer Science and Business Media LLC
A.H.K Owgi, A.A. Jalil, I. Hussain, H.U. Hambali, and Walid Nabgan
Elsevier BV
Bemgba B. Nyakuma, Syie L. Wong, Hasan M. Faizal, Hambali U. Hambali, Olagoke Oladokun, and Tuan Amran T. Abdullah
Springer Science and Business Media LLC
Hambali Umar Hambali, Aishah Abdul Jalil, Abdulrahman A. Abdulrasheed, Tan Ji Siang, Yahya Gambo, and Ahmad Abulfathi Umar
Elsevier BV
H.U. Hambali, A.A. Jalil, S. Triwahyono, S.F. Jamian, N.A.A. Fatah, A.A. Abdulrasheed, and T.J. Siang
Elsevier BV
Tan Ji Siang, Aishah Abdul Jalil, Abdulrasheed Abdulrahman, and Hambali Umar Hambali
Springer Science and Business Media LLC
A. H. K. Owgi, A. A. Jalil, I. Hussain, N. S. Hassan, H. U. Hambali, T. J. Siang, and D. V. N. Vo
Springer Science and Business Media LLC
H.U. Hambali, A.A. Jalil, A.A. Abdulrasheed, T.J. Siang, A.H.K. Owgi, and F.F.A. Aziz
Elsevier BV
I. Hussain, A.A. Jalil, N.S. Hassan, H.U. Hambali, and N.W.C. Jusoh
Elsevier BV
H.U. Hambali, A.A. Jalil, A.A. Abdulrasheed, T.J. Siang, B.B. Nyakuma, W. Nabgan, and T.A.T. Abdullah
Elsevier BV
Hambali Umar Hambali, Aishah Abdul Jalil, Abdulrahman A. Abdulrasheed, Tan Ji Siang, and Dai-Viet N. Vo
Elsevier BV
Hambali U. Hambali, Aishah A. Jalil, Abdulrahman A. Abdulrasheed, Tan J. Siang, Tuan A. T. Abdullah, Arshad Ahmad, and Dai‐Viet N. Vo
Hindawi Limited
A highly active and robust fibrous spherical ZSM‐5‐supported nickel catalyst with different promoters (Mg, Ca, Ta, Ga) have been synthesised by microemulsion method for dry reforming of methane (DRM). The structural framework provided by the unique fibrous spherical ZSM‐5 aided confinement of Ni particles. Catalytic activity was improved by homogenous distribution of surface acid‐basic sites, thereby reducing the propensity of coke deposition. Bimetallic Ni‐Ta catalyst produced the highest CH4 and CO2 conversions at 93% and 98%, respectively, with H2/CO ratio closer to unity (0.97). The nature of acid sites and bimetallic Ni‐Ta synergism amplified interaction of catalyst components, resulting in improved interaction with the reactants, thus impeding metal sintering and coke deposition. Consequently, the Ni‐Ta/FZSM‐5 catalyst shows long‐term activity (80 hours) for the DRM reaction at 800°C.
T.J. Siang, A.A. Jalil, A.A. Abdulrasheed, H.U. Hambali, and Walid Nabgan
Elsevier BV
A F A Rahman, A A Jalil, N W C Jusoh, M Mohamed, N A A Fatah, and H U Hambali
IOP Publishing
Abstract Benzene methylation is an important process for removing excess benzene in petrochemical industries to produce value-added products such as toluene and xylene. In this study, the performance of three types of zeolites, which is ZSM-5 (HZ), zeolite Y (HY) and zeolite β (Hβ) were investigated as catalyst in the benzene methylation reaction. The catalysts were characterized by N2 adsorption-desorption and FTIR. The N2 adsorption-desorption verified that the mesopores volume of the catalysts was in the following order: HB > HY > HZ. While, the FTIR-lutidine revealed that the HB possessed the highest amount of Brönsted acid sites followed by HZ and HY. The catalytic testing at 573 K showed that HZ gave good performance in benzene methylation with 55.2% and 22.1% yield of toluene and xylene, respectively. It is suggested that HZ catalyst with moderate amount of Brönsted acid sites and smallest mesopores volume appear to be effective for shape selective synthesis of toluene and xylene. In addition, pore structure of HZ also contributed to the high catalytic activity of benzene methylation.
A A Abdulrasheed, A A Jalil, T J Siang, and H U Hambali
IOP Publishing
Abstract Thermodynamic sensitivity analysis was conducted to evaluate the selectivity dry reforming of methane (DRM) with respect to other competing side reactions in terms of Gibbs energy minimization and equilibrium reactor compositions. Spontaneity of each reaction was evaluated by their corresponding changes in Gibbs energy as a function of reactor temperature from 100 – 1000 °C. At temperatures above 700 °C, all reactions considered with the exception of the Boudouard reaction are spontaneous due to their negative deltaG values. Equilibrium compositions were computed for 40 kmol of feed (CO2 + CH4) to determine its sensitivity to occurrence of reverse water-gas-shift (RWGS) reaction and changes in feed CO2/CH4 ratio. The presence of RWGS reaction results to higher reactant conversion accompanied by more severe carbon formation. The H2/CO ratio was however not affected by its occurrence. At CO2/CH4 feed ratio of 2, the product ratio was barely affected and at minimal carbon formation while CO2/CH4 ratio value of 0.5 produced a lot of carbon especially at high temperatures due to the prevalence of CH4 cracking. DRM is thus more preferable at temperatures above 700 °C, devoid of RWGS and high feed CH4.
T J Siang, A A Jalil, H U Hambali, A A Abdulrasheedand, and M S Azami
IOP Publishing
Abstract Depletion of fossil fuel for global energy system and increasing concern on global warming have driven the exploration of alternative and sustainable energy source in realms of academia and industry. This study aims to investigate the physicochemical features of KAUST Catalysis Center-1 supported catalyst (i.e., Ni/KCC-1) and evaluate its catalytic performance for Partial Oxidation of Methane (POM) reaction. N2 physisorption and XRD analyses confirmed the structural integrity of KCC-1 framework after NiO addition while the growth of Si–O–Ni bonds in KCC-1 structure was corroborated by the FTIR results. The FESEM and TEM images for KCC-1 not only affirm the successful formation of bicontinuous lamellar morphology but also reveal that the three-dimensional spherical structure was originally developed from the centre of microsphere into all axial. The combustion-reforming pathway was determined during reaction run and the H2/CO ratio ranging of 1.48 to 2.14 was appropriate for synthetic fuel production via Fischer-Tropsch synthesis (FTS).
I Hussain, A A Jalil, N A A Fatah, M. Ibrahim, M S Azami, W Fadlun, M A H Aziz, and HU Hambali
IOP Publishing
Abstract Catalytic CO2 methanation offers an attractive and sustainable way for the production of substituted natural gas (SNG), which may be used as a clean alternative energy source than fossil fuels. A metal-free fibrous silica ZSM-5 catalyst (FS@ZSM-5) was synthesized via the microemulsion technique to conduct catalytic CO2 methanation. The FESEM, BET, and FTIR characterization techniques were used to investigate the surface morphology, pore structure of the catalysts. It was noticed that the commercialized ZSM-5 showed 37% CH4 selectivity with a rate of methane formation 0.067 mmol m−2s−1. While FS@ZSM-5 exhibited high CH4 selectivity of 66 % with rate of methane formation 0.108 mmol m−2s−1 using same conditions (T = 500 °C and GHSV = 36,000 mL h−1 g−1). Therefore, the FS@ZSM-5 was proved an efficient and active catalyst for CO2 methanation activity.