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We report a unique composite of La0.4Sr0.4Ti0.9Ni0.1O3-δ (LSTN) nanoparticles interlaced with two dimensional Ti3C2Tx (MXene) nanosheets, providing high conductivity. LSTN heterostructure synthesized by the sol-gel method produces a large oxygen vacancy and creates a variable valence state while, MXene synthesized from Hydrofluoric acid (HF) treatment resulted in a highly hydrophilic and conductive surface, thereby enhancing the charge transferability. For OER, the LSTN/MXene 66.67% electrode exhibits a benchmark of 10 mA cm−2 at a potential of 1.56 (V vs RHE) in 1 M KOH. It has exhibited the lowest Tafel slope of 44 mV dec−1 and highest mass activity (60 mA g−1 @ 1.59 V) due to quicker ions diffusion and increased available exposed area. Moreover, the efficient LSTN/MXene 66.67% electrode showed good long-term durability during a 24 h stability test at a current density of 100 mA cm−2. The strong interfacial interaction and high charge transfer among LSTN nanoparticles and 2D MXene nanosheets not only provide good structural strength to the composite but also improves the redox activity of LSTN/MXene 66.67% catalyst towards OER. This work provides improved conductive properties of perovskite by developing a composite of perovskite and MXene, that has significantly enhanced electrochemical properties of the catalyst by undergoing fast kinetics.

In this work, partial oxidation of methane (POM) was investigated using Mg-Ni-Al (MNA) hydrotalcite promoted CeO2 catalyst in a fixed bed reactor. MNA hydrotalcite was synthesized using the co-precipitation process, while CeO2 was incorporated via the wetness impregnation technique. The CeO2@MNA samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET) technique. The catalytic activity of CeO2 promoted MNA (CeO2@MNA) for POM reaction was evaluated for various CeO2 loading kept the feed ratio CH4/O2 = 2 at 850 °C. The catalyst containing 10 wt% cerium loading (10%CeO2@MNA) showed 94% CH4 conversion with H2/CO ratio above 2.0, that is more suitable for FT synthesis. The performance of catalyst is attributed to highly crystalline stable CeO2@MNA with better Ce-MNA interactions withstand for 35 h time on stream. Furthermore, the spent catalyst was examined by TGA, SEM-EDS, and XRD to evaluate the carbon formation and structural changes during the span of reaction time.

It is extremely prudent and highly challenging to design a greener bifunctional electrocatalyst that shows effective electrocatalytic activity and high stability toward electrochemical water splitting. As several hundred tons of catalysts are annually deactivated by deposition of carbon, herein, we came up with a strategy to reutilize spent methane reforming catalysts that were deactivated by the formation of graphitic carbon (GC) and carbon nanofibers (CNF). An electrocatalyst was successfully synthesized by in situ deposition of noble metal-free MoS2 over spent catalysts via a hydrothermal method that showed exceptional performance regarding the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). At 25 mA cm–2, phenomenal OER overpotentials (η25) of 128 and 154 mV and modest HER overpotentials of 186 and 207 mV were achieved for MoS2@CNF and MoS2@GC, respectively. Moreover, OER Tafel slopes of 41 and 71 mV dec–1 and HER Tafel slopes of 99 and 107 mV dec–1 were obtained for MoS2@CNF and MoS2@GC, respectively. Furthermore, the synthesized catalysts exhibited good long-term durability for about 18 h at 100 μA cm–2 with unnoticeable changes in the linear sweep voltammetry (LSV) curve of the HER after 1000 cycles. The carbon on the spent catalyst increased the conductivity, while MoS2 enhanced the electrocatalytic activity; hence, the synergistic effect of both materials resulted in enhanced electrocatalysts for overall water splitting. This work of synthesizing enhanced nanostructured electrocatalysts with minimal usage of inexpensive MoS2 gives a rationale for engineering potent greener electrocatalysts.

In this study, Ce0.85-xLa0.15CaxO2-δ was synthesized using sol-gel combustion method and appliedfor partial oxidation of methane (POM). The physicochemical properties of catalyst were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and thermogravimetric analysis (TGA). Material shows a pure cubical structure and is highly stable up to 850 °C. The performance testing indicated the conversion of CH4 is 65% and selectivity of H2 and CO are 28% and 8%, respectively. The performance indicated the catalyst has a potential to be used for partial oxidation of methane on a larger scale. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The objective of this study was to analyze the catalytic performance of series of cobalt-modified Zeolite-4A supported catalysts for the syngas (CO and H2) production at 800 °C via the partial oxidation of methane (POM). The Co/Zeolite-4A catalyst was synthesized using a two-step hydrothermal method from coal fly ash. The synthesized catalysts were characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), and Thermogravimetric Analysis (TGA). The catalyst shows a crystalline structure with stability up to 900 °C. The catalytic performance analysis shows the CH4 conversion increases from 29 to 68% for 0 and 10 wt% Co over Zeolite-4A, respectively. The H2 selectivity was improved from 28–56% while CO selectivity increased from 24–52 % making H2/CO ratio > 1. The stability analysis shows the 10% Co/Zeolite-4A withstand for 24 h a time on stream (TOS). Finally, the spent catalyst analysis was carried out to check the carbon formation along with its structural analysis. The minimal carbon formation is analyzed in 24 h TOS for POM reaction. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The catalyst has a significant role in gas processing applications such as reforming technologies for H2 and syngas production. The stable catalyst is requisite for any industrial catalysis application to make it commercially viable. Several methods are employed to synthesize the catalysts. However, there is still a challenge to achieve a controlled morphology and pure catalyst which majorly influences the catalytic activity in reforming applications. The conventional methods are expansive, and the removal of the impurities are major challenges. Nevertheless, it is not straightforward to achieve the desired structure and stability. Therefore, significant interest has been developed on the advanced techniques to take control of the physicochemical properties of the catalyst through non-thermal plasma (NTP) techniques. In this review, the systematic evolution of the catalyst synthesis using NTP technique is elucidated. The emerging DBD plasma to synthesized and effective surface treatment is reviewed. DBD plasma synthesized catalyst performance in reforming application for H2 and syngas production is summarised. Furthermore, the status of DBD plasma for catalyst synthesis and proposed future avenues to design environmentally suitable and cost-effective synthesis techniques are discussed.

The excess emission of greenhouse gases (GHGs) such as CO2 and CH4 is posing an acute threat to the environment, and efficient ways are being sought to utilize GHGs to produce syngas (H2, CO) and lighter hydrocarbons (HCs). In this study, the dry reforming of methane (DRM) has been carried out at 700 °C using La2O3 co-supported Ni/MgAl2O4 nano-catalyst in a fixed bed thermal reactor. The catalyst is characterized using various techniques such as XRD, FESEM, EDX-mapping, CO2-TPD, H2-TPR and TGA. The modified MgAl2O4 shows the flake type structure after the addition of La2O3. The TPR and TPD analysis shows the highly dispersed metal and strong basic nature of the catalyst consequently enhances the conversion of CO2 and CH4. The highest conversion for CH4 is 87.3% while CO2 conversion is nearly 89.5% in 20 h of operation time. The selectivity of H2 and CO approached 50% making the H2/CO ratio above unity. In the longer time-on-stream (TOS) test, the catalyst shows elevated potential for longer runs showcasing better catalytic activity. The stability of the catalyst is indicated via a proposed reaction mechanism for DRM in operating conditions. Moreover, TGA indicates the lower weight loss of spent catalyst which ascribed the lower formation of carbon during TOS 20 h.

A kinetic study on dry reforming of methane (DRM) in hybrid dielectric barrier discharge (DBD) plasma reactor over La2O3 co-supported Ni/MgAl2O4 catalyst has been investigated. Three different parametric effects namely specific input energy (SIE), discharge volume (VD) and feed flow rate corresponding to GHSV (h−1) are studied using the modified power-law model. The developed kinetic model indicates instantaneous conversions of CH4 and CO2 are functions of SIE, VD and GHSV. Increasing SIE linearly enhances the conversion of CH4 and CO2, while VD displays a non-linear relation with conversion and selectivity. GHSV also shows a linear relation with instantaneous CH4 and CO2 conversion and selectivity of H2 and CO. The rate constants ( k C H 4 , k C O 2 ), determined using the proposed kinetic model and various process parameters, are compared with DRM experimental results for validation. The apparent activation energy (Ea), calculated for CH4 and CO2 using modified Arrhenius equation, are = 32.6 kJ mol−1 (CH4) and Ea = 35.2 kJ mol−1 (CO2), respectively. The modified power-law model is a good preliminary description for future understanding of the overall performance of a hybrid catalytic DBD plasma reactor for DRM.

Numerous attempts have been made to produce new materials and technology for renewable energy and environmental improvements in response to global sustainable solutions stemming from fast industrial expansion and population growth. Zeolites are a group of crystalline materials having molecularly ordered micropore arrangements. Over the past few years, progress in zeolites has been observed in transforming biomass and waste into fuels. To ensure effective transition of fossil energy carriers into chemicals and fuels, zeolite catalysts play a key role; however, their function in biomass usage is more obscure. Herein, the effectiveness of zeolites has been discussed in the context of biomass transformation into valuable products. Established zeolites emphasise conversion of lignocellulosic materials into green fuels. Lewis acidic zeolites employ transition of carbohydrates into significant chemical production. Zeolites utilise several procedures, such as catalytic pyrolysis, hydrothermal liquefaction, and hydro-pyrolysis, to convert biomass and lignocelluloses. Zeolites exhibit distinctive features and encounter significant obstacles, such as mesoporosity, pore interconnectivity, and stability of zeolites in the liquid phase. In order to complete these transformations successfully, it is necessary to have a thorough understanding of the chemistry of zeolites. Hence, further examination of the technical difficulties associated with catalytic transformation in zeolites will be required. This review article highlights the reaction pathways for biomass conversion using zeolites, their challenges, and their potential utilisation. Future recommendations for zeolite-based biomass conversion are also presented.

Ni/La2O3-MgAl2O4 has been investigated for dry reforming of methane (DRM) in a cold plasma dielectric barrier discharge (DBD) fixed-bed reactor. Ni/La2O3-MgAl2O4 was prepared according to the modif...

In this study, 10% Ni/La2O3 MgAl2O4 nano-flake catalyst was synthesized, characterized and tested in a catalytic dielectric barrier discharge (DBD) plasma for dry reforming of methane (DRM). With design of experiment (DoE), the influence of process parameters namely (1) total feed flow rate (ml min−1), (2) feed ratio (CO2/CH4), (3) input power (W) and (4) catalyst loading (g) were examined using multiple response surface methodology (RSM) through a four-factor, five-level central composite design (CCD). Second-order regression models were applied for evaluating the interaction between the process parameters and responses. Input power (X3) and total feed flow rate (X1) were the two most influential process parameters followed by catalyst loading (X4) and feed ratio (X2). The experimental and predicted results from the optimum conditions fitted-well with less than ±5% margin of error. The possible dynamic interactions between the process variables were elucidated. The optimum values are feed flow rate = 18.8 ml min−1, feed ratio = 1.05, input power = 125.6 W and catalyst loading = 0.6 g. At these conditions, the predicted CH4 and CO2 conversions are 79.86% and 84.03%, respectively. The H2 and CO yields are predicted as 41.37% and 40.47%, respectively while H2/CO ratio is above unity. The calculated EE from the RSM model is predicted as 0.135 mmol kJ−1. Low carbon deposition observed on the spent catalyst is attributed to the highly basic and oxidative nature of the La2O3 co-supported catalyst.

Dry reforming of methane (DRM) is one of the attractive methods for the utilisation of greenhouse gases (e.g., CH4, CO2) to produce valuable fuels. In the quest for an efficient development in DRM, several technologies have been practised, while dielectric barrier discharge (DBD) cold plasma technology garners special attention in the utilisation of CO2 and CH4 through DRM process due to easy upscaling opportunities and mild operating conditions. However, the low energy efficiency (EE) of DBD plasma is a distinct challenge and it offers an in-depth insight into its basic operational understandings. This review presents the overall status and current developments in DBD plasma for DRM. In the mainstream, challenges in DBD plasma technology, catalyst-plasma interactions and developments in plasma catalysts to improve the yield and selectivity of DRM have been discussed. The current status and developments in DBD reactor configuration based on reactor geometry, such as the electrode morphology, discharge gap (Dgap), discharge volume (VD) and material packing to maximise the productivity of DRM are specifically investigated. The effects of the operating parameters, such as gas hourly space velocity (GHSV), specific input energy (SIE) and feed ratio are critical for product distribution. The current status of reaction kinetics and prospects in fluid modelling of catalytic DBD plasma DRM reactor is reviewed to understand the underlying reaction mechanism. Finally, further advancements in the catalytic DBD plasma DRM has become a requisite to make it commercially viable for the successful production of valuable fuels.

Syngas is a valuable entity for downstream liquid fuel production and chemical industries. The efficient production of syngas via catalytic partial oxidation of methane (CPOM) is an important process. In this study, partial oxidation of methane (POM) was carried out using CaO decorated TiO2 catalysts. The catalysts were synthesized employing the sol-gel method, while the decoration of TiO2 with CaO was achieved in an aqueous solution by wetness impregnation method. The prepared catalysts were characterized by employing XRD, Raman, TG-DTG, and SEM-EDX for structural and morphological analysis. On testing for POM, at 750 °C the catalysts demonstrate excellent CH4 conversion of 83.6 and 79.5% for 2% and 3% CaO loaded TiO2, respectively. While the average H2/CO ratio for both 2% and 3% CaO loaded TiO2, 2.25 and 2.28, respectively, remained slightly above the theoretical value (H2/CO = 2.0) of POM. The improved POM performance is attributed to the optimally loaded CaO on the TiO2 surface that promotes the reaction where TiO2 support ensure less agglomerated particles, resulting into a fine distribution of the active catalytic sites.

Biochar (BC) based materials are solid carbon enriched materials produced via different thermochemical techniques such as pyrolysis. However, the non-modified/non-activated BC-based materials obtained from the low-temperature pyrolysis of biomass cannot perform well in energy storage applications due to the mismatched physicochemical and electrical properties such as low surface area, poor pore features, and low density and conductivity. Therefore, to improve the surface features and structure of the BC and surface functionalities, surface modifications and activations are introduced to improve its properties to achieve enhanced electrochemical performance. The surface modifications use various activation methods to modify the surface properties of BC to achieve enhanced performance for supercapacitors in energy storage applications. This article provides a detailed review of surface modification methods and the application of modified BC to be used for the synthesis of electrodes for supercapacitors. The effect of those activation methods on physicochemical and electrical properties is critically presented. Finally, the research gap and future prospects are also elucidated.

Biomass pyrolysis produces valuable solid, liquid, and gas products. However, the liquid products observed low heating value due to low hydrocarbon contents with the presence of high oxygenated species. To upgrade the bio-oil, appropriate solid acid catalysts are incorporated in the biomass pyrolysis process to deoxygenate the species to enhance the heating value of the bio-oil called catalytic upgrading process. The study presents the progress of catalytic pyrolysis process using shape-selective zeolites for improving hydrocarbon in the bio-oil. To compare the performance, commercial and synthesis microporous zeolites are tested in the in situ catalytic pyrolysis process. ZSM-5, ferrite, and mordenite were the commercial zeolites at the Si/Al ratio of 23, 20, and 20, respectively, are employed. On the other hand, layered MCM-22 (20) and its counterpart ITQ-2 (20) were synthesized using established protocol and tested in catalytic biomass pyrolysis process in drop-type pyrolyzer. These zeolites are categorized as various pore sizes, shapes, and acidity which impacts on deoxygenation performance. Among synthesized zeolites, ITQ-2 showed higher deoxygenation which results in increased aromatics production. Overall, ZSM-5 appeared as the most suitable catalyst for higher deoxygenation with higher aromatics production in comparison to other shape-selective zeolites.

The study experimentally investigated a novel approach for producing hydrogen from methane cracking in dielectric barrier discharge catalytic plasma reactor using a nanocatalyst. Plasma-catalytic methane (CH4) cracking was undertaken in a dielectric barrier discharge (DBD) catalytic plasma reactor using Ni/MgAl2O4. The Ni/MgAl2O4 was synthesised through co-precipitation followed customised hydrothermal method. The physicochemical properties of the catalyst were examined using X-ray diffraction (XRD), scanning electron microscopy—energy dispersive X-ray spectrometry (SEM-EDX) and thermogravimetric analysis (TGA). The Ni/MgAl2O4 shows a porous structure spinel MgAl2O4 and thermal stability. In the catalytic-plasma methane cracking, the Ni/MgAl2O4 shows 80% of the maximum conversion of CH4 with H2 selectivity 75%. Furthermore, the stability of the catalyst was encouraging 16 h with CH4 conversion above 75%, and the selectivity of H2 was above 70%. This is attributed to the synergistic effect of the catalyst and plasma. The plasma-catalytic CH4 cracking is a promising technology for the simultaneous H2 and carbon nanotubes (CNTs) production for energy storage applications.

Dry reforming of methane (DRM) to syngas in a dielectric barrier discharge (DBD) plasma reactor over Ni-loaded ɤ-Al2O3-MgO nanocomposite catalysts has been investigated. The catalysts are prepared by modified incipient wetness impregnation method, assisted by cold plasma treatment. The samples are characterized by XRD, N2 adsorption-desorption, H2-TPR, CO2-TPD, FESEM and EDX. The performance of the catalyst for DRM is evaluated at various specific input energy (SIE J ml−1) and gas hourly space velocity (GHSV, h−1). The maximum conversion achieved are 74.5% and 73% for CH4 and CO2 respectively, over 10% Ni/ɤ-Al2O3-MgO at specific input energy (SIE) = 300 J ml−1 and gas hourly space velocity (GHSV) = 364 h−1. The main reaction products are H2 (29.5%), CO (30.5%) with H2/CO = 1 inferring RWGS reaction is suppressed for 12 h operation time. The enhanced conversion and yield are due to the strong metal-support interaction, high Lewis basicity and stable 10% Ni/ɤ-Al2O3-MgO catalyst as well as the plasma-catalyst interface. The energy efficiency (EE) of the plasma-catalytic DRM is higher (0.117 mmol kJ−1) compared to plasma only (0.087 mmol kJ−1) demonstrating the synergy between catalyst and plasma. The reaction mechanism is also proposed to postulate the steps involved in the DRM.

The utilisation of methane (CH4) to produce syngas (H2, CO) via partial oxidation of methane (POM) is an attractive technique, as syngas is a very valuable entity to produce liquid fuels and fuel cell applications. This work presents the hydrothermal growth of ZnO nanoprisms (ZnO-NPr) in a dual solvent for a controlled structure. The Co-Ni loaded ZnO-NPr catalysts were obtained in an aqueous solution by wetness impregnation method and tested for POM for the first time. The synthesized catalysts were characterized by employing XRD, SEM-EDX, TGA and RAMAN spectroscopy for structural and morphological analysis. The catalysts were analyzed for POM at 850 ᵒC and demonstrated high catalytic activity. It was observed that the catalytic activity of Co loaded ZnO-NPr, and Ni-Co loaded ZnO-NPr was more and demonstrated the stable behaviour for CH4 conversion in comparison to Ni loaded catalysts. The Co-Ni loaded ZnO-NPr has shown a high CH4 conversion (XCH4) (98%), and excellent stability over 56 h on stream. The average value of H2/CO for Co-Ni loaded ZnO-NPr was 2.11, above the theoretical value for POM. It is attributed to the better performance of catalyst towards the selectivity of H2 in reaction pathways.

In this work, the biomass fly ash (BFA) was investigated as a potential catalyst for the thermo-catalytic decomposition of methane and attractive approach for hydrogen (H2) production. The BFA based CeO2 nanowires promoted cobalt catalyst was synthesized for catalytic methane (CH4) decomposition and was tested in a fixed bed reactor. The physicochemical properties of the catalyst were investigated using various techniques such as X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, thermal gravimetric analysis, and Fourier transformed infrared. The pure crystalline micro-flake BFA was modified using synthesized CeO2 nanowires and the resulted micro flakes cross-linked with nanowires shown thermal stability up to 900 °C. The high stability of the catalyst makes it suitable for the thermal catalytic decomposition of methane. The activity of the catalyst was tested at 850 °C to analyze the H2 production and CH4 conversion. The obtained results revealed that support and promoter exhibit a strong impact on the CH4 conversion and H2 yield in catalyst screening tests. A maximum conversion of 71% for CH4 with 44.9% H2 yield was recorded for 34 h on stream activity while using 5% Co/CeO2-BFA as the catalyst. While BFA and Co-BFA as catalyst showed 36% and 47% conversion of CH4, respectively which indicates that the addition of promoter shows an increase in values of both conversion of CH4 and H2 yield. Compared to traditional catalyst support, the use of waste-sourced catalyst support for CH4 decomposition provides a greener and more economical route for H2 production.

Co/TiO2–MgAl2O4 was investigated in a fixed bed reactor for the dry reforming of methane (DRM) process. Co/TiO2–MgAl2O4 was prepared by modified co-precipitation, followed by the hydrothermal method. The active metal Co was loaded via the wetness impregnation method. The prepared catalyst was characterized by XRD, SEM, TGA, and FTIR. The performance of Co/TiO2–MgAl2O4 for the DRM process was investigated in a reactor with a temperature of 750 °C, a feed ratio (CO2/CH4) of 1, a catalyst loading of 0.5 g, and a feed flow rate of 20 mL min−1. The effect of support interaction with metal and the composite were studied for catalytic activity, the composite showing significantly improved results. Moreover, among the tested Co loadings, 5 wt% Co over the TiO2–MgAl2O4 composite shows the best catalytic performance. The 5%Co/TiO2–MgAl2O4 improved the CH4 and CO2 conversion by up to 70% and 80%, respectively, while the selectivity of H2 and CO improved to 43% and 46.5%, respectively. The achieved H2/CO ratio of 0.9 was due to the excess amount of CO produced because of the higher conversion rate of CO2 and the surface carbon reaction with oxygen species. Furthermore, in a time on stream (TOS) test, the catalyst exhibited 75 h of stability with significant catalytic activity. Catalyst potential lies in catalyst stability and performance results, thus encouraging the further investigation and use of the catalyst for the long-run DRM process.

The development of bifunctional electrocatalyst with effective activity and high stability for water splitting reactions is essential for hydrogen production and fuel cell technology. Herein, a 3D hierarchical heterostructure LSTN@NiMn-layered double hydroxide (La0.4Sr0.4Ti0.9Ni0.1O3-δ @NiMn-LDH) supported on highly conductive nickel foam, is presented as a novel bifunctional electrocatalyst with outstanding performance. LSTN heterostructure synthesized by sol-gel method followed by hydrothermal reaction to grow LDH layers (LSTN@NiMn-LDH) resulted in phenomenal bifunctional activity towards both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), by exhibiting a low overpotential of 125 mV at 15 mA cm−2 (OER) and 32 mV at 10 mA cm−2 (HER). Moreover, the 3D electrode showed good long-term durability for 24 hrs. stability test at a current density of 100 µA cm−2, as well as constant LSV results after operating HER for 1000 cycles. This approach of preparing heterostructure LSTN@NiMn-LDH combines the fundamental properties of La0.4Sr0.4Ti0.9Ni0.1O3-δ (highly efficient HER catalyst) with NiMn-LDH (catalytically active for OER) by using interface engineering, resultantly opens a new way of enhancing the overall activity of water splitting reactions.

The biomass utilization for power generation is one of the efficient pathways to reduce greenhouse gas emissions. However, the high ash formation in biomass fed power plants raises several concerns, especially ash handling and its utilization. In this study, the biomass ash characterization, ash fusion analysis and its utilization as a catalyst in methane (CH4) decomposition were systematically investigated. The biomass bottom ash (BBA) and biomass fly ash (BFA) were modified using laboratory synthesized CeO2 nanoparticles to enhance the fusion temperature. The BBA, BFA and modified CeO2-BBA/BFA samples were characterized by ultimate analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF) analysis to investigate the physicochemical properties and its suitability for the catalysis applications. The detailed characterization inferred that BFA has significant potential in improving the ash fusion temperature as well as suitable for catalysis of fuel processing due to the presence of metal oxides such as Fe2O3, SiO2, CaO, Al2O3 and its porous structure. Furthermore, the most suitable BFA was impregnated with cobalt (Co). Co loaded BFA was employed for CH4 decomposition at 700 °C for H2 production in a fixed bed reactor. The Co/BFA demonstrated a stable catalytic activity of more than 330 min on stream with optimum H2 yield of 30%. The direct employment of BFA as catalyst support shows potential in further catalytic applications and material applications.

Catalytic and thermal cracking of polypropylene was performed in a batch reactor. Effect of hydrochloric acid activation on kaolin clay, effects of catalysts (acid-activated clays), promoter (5 wt% Ni), and cracking temperatures on the liquid oil yield were investigated. Results show optimized liquid yield (71.9%) obtained at 470°C with kaolin clay activated with 3 M HCl. Acid-activated catalysts were analyzed using XRD and the results reveal the reduction in peaks’ intensities. Weight loss of polypropylene was investigated by thermogravimetric analysis. FTIR and GCMS techniques were employed to analyze the liquid products.

Fabrication of reducible titanium dioxide (TiO2) loaded with nickel (Ni) to maximize metal-support interaction for stimulating hydrogen (H2) production via phenol steam reforming (PSR) has been investigated. Catalysts, synthesized by sol-gel assisted impregnation method, were characterized by XRD, FE-SEM, EDX, BET, H2-TPR and TEM techniques. The effects of three different catalyst sizes namely Ni/TiO2-A (11−49 nm), Ni/TiO2-B (22−196 nm) and Ni/TiO2-C (69−205 nm) for their mass transfer limitation, catalytic activity and coke formations were evaluated. Using smaller particle sizes of TiO2 higher BET surface area with good morphology and Ni dispersion was achieved. The Ni/TiO2-A sample shows highest phenol reforming activity with phenol conversion and H2 yield of 98.3 and 76.9 %, respectively. When large sizes TiO2 particles in Ni/TiO2-B and Ni/TiO2-C samples were employed, phenol conversion of 93.7 and 73.1 % and H2 yield of 71.2 and 55.6%, respectively, were achieved. This reveals that smaller support particle sizes have higher conversion and yields, and activity was declined when support size was increased to larger particle sizes. This was obviously small particle sizes resulted in larger surface area, higher metal dispersion and efficient surface reactions with minimum internal diffusion effects. Furthermore, stability analysis reveals continuous H2 production over smaller particles without obvious deactivation, however, activity was declined over time on stream using large support size due to obvious coke depositions. Thus, supports sizes and interaction of metal and support has significant contribution to maximize activity and stability and can be further employed in reforming systems for renewable hydrogen production.