Calcium-based mixed oxides catalysts (CaMgO and CaZnO) have been investigated for the transesterification of Jatropha curcas oil (JCO) with methanol, in order to evaluate their potential as ...heterogeneous catalysts for biodiesel production. Both CaMgO and CaZnO catalysts were prepared by coprecipitation method of the corresponding mixed metal nitrate solution in the presence of a soluble carbonate salt at ∼ pH 8–9. The catalysts were characterized by X-ray diffraction (XRD), temperature programmed desorption of CO2 (CO2-TPD), scanning electron microscopy (SEM) and N2 adsorption (BET). The conversion of JCO by CaMgO and CaZnO were studied and compared with calcium oxide (CaO), magnesium oxide (MgO) and zinc oxide (ZnO) catalysts. Both CaMgO and CaZnO catalysts showed high activity as CaO and were easily separated from the product. CaMgO was found more active than CaZnO in the transesterification of JCO with methanol. Under the suitable transesterification conditions at 338 K (catalyst amount = 4 wt. %, methanol/oil molar ratio = 15, reaction time = 6 h), the JCO conversion of more than 80% can be achieved over CaMgO and CaZnO catalysts. Even though CaO gave the highest activity, the conversion of JCO decreased significantly after reused for forth run whereas the conversion was only slightly lowered for CaMgO and CaZnO after sixth run.
The inflammatory response is a crucial aspect of the tissues' responses to deleterious inflammogens. This complex response involves leukocytes cells such as macrophages, neutrophils, and lymphocytes, ...also known as inflammatory cells. In response to the inflammatory process, these cells release specialized substances which include vasoactive amines and peptides, eicosanoids, proinflammatory cytokines, and acute-phase proteins, which mediate the inflammatory process by preventing further tissue damage and ultimately resulting in healing and restoration of tissue function. This review discusses the role of the inflammatory cells as well as their by-products in the mediation of inflammatory process. A brief insight into the role of natural anti-inflammatory agents is also discussed. The significance of this study is to explore further and understand the potential mechanism of inflammatory processes to take full advantage of vast and advanced anti-inflammatory therapies. This review aimed to reemphasize the importance on the knowledge of inflammatory processes with the addition of newest and current issues pertaining to this phenomenon.
► Production of biodiesel via heterogeneous catalytic reaction with nonedible oil. ► Effect of Ca/Mg ratio towards transesterification activity was studied. ► We examine correlative effect between ...activity and alkalinity of the catalyst. ► 90% of FAME content is achieved under mild reaction condition. ► CaO–MgO catalyst showed high reusability with reused up to 4 times (>80%).
Heterogeneous base catalysts were studied to develop an effective biodiesel manufacturing process with high activity and durability. Investigations were conducted on solid base CaO–MgO mixed metal oxides with different Ca/Mg atomic ratios. These catalysts were characterized by X-ray diffraction (XRD), nitrogen sorption with Brunauer–Emmer–Teller method (BET surface area), scanning electron microscopy (SEM) with energy dispersive X-ray (EDS) spectroscopy and temperature-programmed desorption of CO
2 (TPD-CO
2). The catalytic activity was evaluated by transesterification of non-edible oil (
Jatropha curcas oil) to its corresponding fatty acid methyl ester. Under optimum condition: 3
h reaction time, 25:1 methanol/oil molar ratio, 3
wt.% catalyst loading and 120
°C reaction temperature, a series of calcium-based mixed oxide catalysts with different Ca/Mg atomic ratio produced a FAME yield in the range of 75–90%.
Reliable and sustainable energy supply is critical to effective natural resource management, and it encompasses functioning efficiency of energy resources as well as socio-economic and environmental ...impact considerations. The complete reliance on fossil fuels is recognized as unsustainable throughout the world, and this is due to, amongst others, the rapid declining of fossil fuel reserves and the emission of significant quantities of greenhouse gases associated with their production and combustion. This has resulted in escalating interest in research activities aiming to develop alternative and somewhat carbon neutral energy sources. Algal biofuels, so called third generation biofuels, appear to be promising in delivering sustainable and complementary energy platforms essential to formulate a major component of the renewable and sustainable energy mix for the future. Algal biomass can be converted into various portfolios of biofuel products, such as bio-hydrogen, biodiesel, bioethanol and biogas, via two different pathways: biochemical and thermochemical pathways. Thermochemical conversion is considered as a viable method to overcome the existing problems related with biochemical conversion such as lengthy reaction time, low conversion efficiency by microbes and enzymes, and high production costs. This paper discusses process technologies for microalgae-to-biofuel production systems, focusing on thermochemical conversion technologies such as gasification, pyrolysis, and liquefaction. The benefits of exploiting upstream microalgal biomass development for bioremediation such as carbon dioxide mitigation and wastewater treatment are also discussed.
Oil palm is one of the major economic crops in many countries. Malaysia alone produces about 47% of the world's palm oil supply and can be considered as the world's largest producer and exporter of ...palm oil. Malaysia also generates huge quantity of oil palm biomass including oil palm trunks, oil palm fronds, empty fruit bunches (EFB), shells and fibers as waste from palm oil fruit harvest and oil extraction processing. At present there is a continuously increasing interest in the utilization of oil palm biomass as a source of clean energy. One of the major interests is hydrogen from oil palm biomass. Hydrogen from biomass is a clean and efficient energy source and is expected to take a significant role in future energy demand due to the raw material availability.
This paper presents a review which focuses on different types of thermo-chemical processes for conversion of oil palm biomass to hydrogen rich gas. This paper offers a concise and up-to-date scenario of the present status of oil palm industry in contributing towards sustainable and renewable energy.
Calcined dolomite (AD), produced by calcination of Malaysian dolomite (UD) promotes a potential natural catalyst for biodiesel production from palm oil with the conversion of 99.98%. The catalysts ...were characterized by using X-ray Diffractometer (XRD), Brunauer-Emmet-Teller (BET) surface area, Scanning Electron Microscopy (SEM) and Temperature Programmed Desorption (TPD) of CO2. All catalysts were then employed for transesterification reaction under different conditions (time, methanol to oil molar ratio and amount of catalyst). SnO2 doped on activated dolomite (SD) shows an optimum conversion (99.98%) at conditions, i.e. 15:1 methanol to oil molar ratio in 4 h compared to ZnO doped on activated dolomite (ZD) and AD. The catalytic activities of these catalysts were found to be depending on the basicity as well as the surface area of the catalyst used.
Deoxygenation processes that exploit milder reaction conditions under H
2
-free atmospheres appear environmentally and economically effective for the production of green diesel. Herein, green diesel ...was produced by catalytic deoxygenation of chicken fat oil (CFO) over oxides of binary metal pairs (Ni-Mg, Ni-Mn, Ni-Cu, Ni-Ce) supported on multi-walled carbon nanotubes (MWCNTs). The presence of Mg and Mn with Ni afforded greater deoxygenation activity, with hydrocarbon yields of >75% and
n
-(C
15
+ C
17
) selectivity of >81%, indicating that decarboxylation/decarbonylation (deCOx) of CFO is favoured by the existence of high amount of lower strength strong acidic sites along with noticeable strongly basic sites. Based on a series of studies of different Mg and Mn dosages (5-20 wt%), the oxygen free-rich diesel-range hydrocarbons produced efficiently by Ni
10
-Mg
15
/MWCNT and Ni
10
-Mn
5
/MWCNT catalysts yielded >84% of hydrocarbons, with
n
-(C
15
+ C
17
) selectivity of >85%. The heating value of the green diesel obtained complied with the ultra-low sulphur diesel standard.
Deoxygenation processes that exploit milder reaction conditions under H
2
-free atmospheres appear environmentally and economically effective for the production of green diesel.
Biodiesel of non food vegetal oil origin is gaining attention as a replacement for current fossil fuels as its non-food chain interfering manufacturing processes shall prevent food source competition ...which is expected to happen with current biodiesel production processes. As a result, non edible
Jatropha curcas plant oil is claimed to be a highly potential feedstock for non-food origin biodiesel. CaO–MgO mixed oxide catalyst was employed in transesterification of non-edible
J. curcas plant oil in biodiesel production. Response surface methodology (RSM) in conjunction with the central composite design (CCD) was employed to statistically evaluate and optimize the biodiesel production process. It was found that the production of biodiesel achieved an optimum level of 93.55% biodiesel yield at the following reaction conditions: 1) Methanol/oil molar ratio: 38.67, 2) Reaction time: 3.44
h, 3) Catalyst amount: 3.70
wt.%, and 4) Reaction temperature: 115.87
°C. In economic point of view, transesterification of
J. curcas plant oil using CaO–MgO mixed oxide catalyst requires less energy which contributed to high production cost in biodiesel production. The incredibly high biodiesel yield of 93.55% was proved to be the synergetic effect of basicity between the active components of CaO–MgO shown in the physicochemical analysis.
► Optimization study for heterogeneous route biodiesel production by RSM technique. ► 93% of biodiesel obtained at mild condition: 3.7
wt.% catalyst, 3.44
h and 115
°C. ► The RSM model showed predictability and accuracy result as experimental values. ► CaO–MgO reused >
4 runs with maintaining >
80% of biodiesel (low leaching of Ca
2+).
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•Development of high acidity HTC-S catalyst via hydrothermal method-H2SO4 activation.•Acidic strength of HTC-S increased by the strong interaction of -SO3H group.•HTC-S catalyst ...rendered high esterification activity with FFA conversion up to 92%.•H2SO4 treatment was an effective technique to maintain catalyst stability.
Low-cost biodiesel was successfully produced through esterification of palm fatty acid distillate over corncob residue-derived heterogeneous solid acid catalyst. The sulfonated functionalized carbon derived from corncob was synthesized via hydrothermal carbonization followed by chemical activation using concentrated sulfuric acid. This technique allows efficient carbonization process and able to maintain active polar species of the catalyst hence effectively improves the acid strength of prepared catalyst. The esterification of palm fatty acid distillate over HTC-S catalyst was optimized via the one-variable-at-a-time technique, and 92% free fatty acid conversion with a biodiesel yield of 85% was achieved at optimum conditions of 2 h reaction time, 70 °C reaction temperature, 3 wt% catalyst loading, and 15:1 methanol-to-oil molar ratio. Various of catalyst regeneration techniques have been studied and sulfuric acid treatment is found to be the most effective approach for restoring the active sites for spent HTC-S catalyst in comparison to washing solvent and thermal treatment. The HTC-S catalyst regenerated via sulfuric acid treatment is capable to convert PFAD to biodiesel with free fatty acid conversion >90% for two consecutive cycles. The synthesized PFAD-derived biodiesel has complied with the international biodiesel standard ASTM D6751.
A design was developed for the transesterification reaction of non-edible Jatropha Curcas oil using a heterogeneous catalysis system to replace the use of a homogeneous catalytic reaction. ...Investigations were conducted on solid MgO–ZnO mixed metal oxide catalyst bases with different atomic ratios of magnesium to zinc (Mg/Zn). These catalysts were characterized by BET (Brunauer–Emmer–Teller) surface area analysis, X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS), and the alkalinity of the catalysts was studied by Temperature Programmed Desorption of carbon dioxide (TPD-CO2). The physicochemical properties of the MgO–ZnO binary system were superior to those of the individual bulk oxides of MgO and ZnO. In addition, the formation of a binary system between MgO and ZnO established an effective method for transesterification processes. In this study, the effects of stoichiometric composition and surface characteristics on the transesterification activity of MgO–ZnO were investigated. The catalysts exhibited high catalytic activity (∼80%) with reliable reusability for biodiesel production.
► Transesterification reaction of non-edible jatropha oil using solid base catalyst. ► MgO–ZnO binary system showed superior effect than the individual MgO and ZnO. ► More than 80% of FAME yield was achieved under mild condition. ► MgO–ZnO catalyst showed reliable reusability throughout 5 runs. ► Fuel properties of prepared biodiesel were complying with the biodiesel standards.
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