Papers by Keyword: Heterogeneous Catalyst

Abstract: This work presents the synthesis and characterization of mixed rare earths hydroxide heterogeneous catalyst. The catalysts were prepared by co-precipitation of mixed rare earths with NaOH at different pH (6, 7 and 12). The prepared catalysts were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS). The XRF results showed that the catalyst composed of cerium (Ce), neodymium (Nd), lanthanum (La), praseodymium (Pr) and samarium (Sm) being predominant at pH up to 7. Particularly, cerium (Ce) was favorable precipitation at pH 7. This results were confirm by SEM-EDS. The Ce (OH)₃ phase was clearly observed for the mixed rare earth catalyst precipitated at pH 7. The XRF, SEM-EDS and XRD results were consistency.

Abstract: Candlenut shell is an agricultural waste which can be processed into low-cost active carbon. Activated carbon cannot be used directly as a heterogeneous catalyst in transesterification of biodiesel because of its low alkalinity, thus treatment is required. In this study, the carbonization of candlenut shells was conducted at 500°C for 4 h. The activated carbon obtained was modified by impregnation with potassium hydroxide (KOH) solution. KOH concentration used was 50g/150 ml aqua des and impregnation time was 24 h. The impregnated activated carbon was characterized by Scanning Electron Microscopy - energy dispersive spectroscopy (SEM-EDS), Fourier Transform Infrared (FTIR) spectroscopy, and was further tested as a heterogeneous catalyst for biodiesel production.

Abstract: A novel geopolymer supported nanobimetallic catalyst for isopropanol dehydrogenation was prepared by modified wet impregnation and reduction method. XRD, SEM, EDX and TEM analysis confirmed formation of amorphous geopolymer from the polymerization of metakaolin and deposition of nanometals over the geopolymer support. The bimetallic catalyst containing 5wt. % Cu and 10wt. % Ni loading over geopolymer shows an excellent performance with 23.18% conversion of isopropanol and 88.24% selectivity to acetone under reaction conditions of 90 °C, 3 hours, and catalyst amount of 0.15g/5.0g of isopropanol. Moreover, the catalyst maintains its catalytic stability without noticeable loss of activity after five cycles.

Abstract: Nowadays, researchers have made attempts to seek for cost-effective and eco-friendly catalyst for transesterification reaction. One possible way to reduce the costs of the catalysts is to use biomass or industrial waste as catalytic materials. The use of waste materials as catalysts also reduces the cost of waste handling and disposal. The objective of this study was to investigate the potential of the low cost, environmentally friendly calcined marlstones to be a viable catalyst in the transesterification of Jatropha seed oil. The calcination of marlstones was conducted at 900 °C for 4 h, and then the modification of calcined marlstones via hydration-dehydration treatment. The effects of different preparation conditions on biodiesel yield were investigated. The solid catalyst was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and the Brunauer-Emmett-Teller (BET) method. The highest biodiesel yield of 97.56% for modified calcium oxide (CaO) catalyst was obtained under the optimum condition (reaction time 5 min, microwave power 600 W, methanol/oil molar ratio 9:1, and catalyst dosage 7 wt%). It was showing potential applications of novel catalyst in biodiesel industry.

Abstract: Nowadays, utilization of biomass is considered to have the potential to solve many environmental problems and provide a source of renewable and environmentally-friendly energy. Research on green and low cost catalysts is needed for economical production of biodiesel. The goal of this work was to test potassium iodide (KI)-impregnated calcined razor clam shell as a heterogeneous catalyst for transesterification of Jatropha curcas oil in a microwave reactor. The effects of different preparation conditions on biodiesel yield were investigated and the structure of the catalyst was characterized. The raw material and the resulting solid catalyst were characterized using X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and the Brunauer-Emmett-Teller (BET) method. The waste shell displays a typical layered architecture. The sample had the surface area 16.51 m²/g, pore diameter 22.18 nm and pore volume 0.14 cm³/g, and presented a uniform pore size. The highest fatty acid methyl ester (FAME) yield of 96.99% for potassium iodide-calcium oxide (KI-CaO) catalyst was obtained under the optimum condition (reaction time 5 min, microwave power 600 W, methanol/oil molar ratio 12:1, and catalyst dosage 3 wt%). It was showing potential applications of catalyst in biodiesel industry.

Abstract: In recent years, attention has been drawn to produce heterogeneous catalyst to replace homogeneous catalyst in biodiesel industry. This study was focused on the synthesis of three different types of alginate based heterogeneous catalyst (Ferric-alginate, Copper-alginate, and Nickel alginate) and the effect of the catalyst on esterification of oleic acid. Morphology and elemental analysis was conducted to investigate the properties of the catalyst. The new heterogeneous catalysts were used to catalyze the esterification of oleic acid at reaction temperature of 60°C and 2 hours reaction time. Fe-alginate has achieved the highest free fatty acids (FFAs) conversation rate of 82.03%. The results and findings proved that transition metal-alginate heterogeneous catalyst has the potential and ability to esterify the free fatty acids prior biodiesel production from high free fatty acids feedstock.

Abstract: Currently, the major concern in production of biodiesel is to find a new catalyst which can produce high quality of biodiesel at lower costs. In this study, titania supported CaO catalyst was prepared by a so-gel method. The characterization of catalyst was done using Brunauer-Emmett-Teller (BET) model method to characterize the surface area of the catalyst. Further, the ability of the catalyst for transterification reaction of waste cooking oil (WCO) with methanol was also assessed. The effect of calcination temperature on the catalyst to the transesterification reaction was examined to investigate the relation between catalyst calcination temperature and percentage yield (% yield) of biodiesel production.

Abstract: Biodiesel is clear liquid with a light to dark yellow color. Biodiesel is one of the alternative fuels that are attractive because of its favorable characteristics such as being non-toxic, biodegradable, renewable, carbon neutral and low emission. Fatty acid methyl ester (FAME) is a type of biodiesel. In this study, it was produced by using transesterification of waste cooking oil (WCO) which was reacted with methanol and heterogeneous catalyst. The two heterogeneous catalysts that were used in this study were sodium (Na) metal hydroxide supported on oil palm frond (OPF) and Na metal supported on oil palm kernel shell (OPKS). The support metal used was sodium hydroxide solution (NaOH). OPF and OPKS were used as they are the major residues obtained from the oil palm plantation that covers approximately 14.72% of Malaysian’s total landmass. The parameters that in this study were the reaction temperatures of the transesterification process from 30°C to 60°C and the catalyst loading from 0.5wt% to 3wt%. The reaction time and ratio methanol to oil were kept constant which were 4 hours and 1:10 respectively. This experiment was conducted in order to investigate the effect of two different heterogeneous catalysts on both temperature and catalyst loading on the yield production of FAME. The results were obtained by using GCMS analysis. From the experiment that was conducted, the results of FAME production by using two different catalysts indicate that the higher the reaction temperature is, the higher the production of FAME which is at 60°C. It also shows that the percentage yield of FAME increases with the increase of catalyst loading until it reaches the best value which is at 1wt%.

Abstract: A selective hydrogenolysis of glycerol has been attempted using an active nanosize and bulk size of Ru/FTO catalyst. The two approaches gives 1,2-propanediol as a main product. The higher conversion and selectivity was obtained at 99% and 94% for the bulky size of the catalyst, while nanosize catalyst give 89% of glycerol conversion and 97% 1,2-PDO selectivity. The Ru/FTO (7.5%) of metal loading, 150°C, 20 bar hydrogen pressure, and 8h was observed as an optimized reaction condition.

Abstract: This paper discusses the influence of residence time and iron concentration factors on the impregnation yield for preparation of the carbon nanofiber supported iron material by incipient wetness impregnation. The samples were characterized by nitrogen physisorption, thermogravimetric analysis and electron spectroscopy techniques. The technique of effective impregnation was studied by atomic adsorption spectrophotometry. The results show that the morphology of the iron was distributed and well supported and the size of iron was in a wide range of 1μm to less than 2nm. The impregnation yield has been achieved 78% for 3 hours of residence time of 3%wt Fe/CNF sample with surface area of 102.292 m²/g.