Transesterification of palm oil for biodiesel production using ni / cao supported with alumina beads / Zainal Kifli Abdul Razak ... [et al].

Biodiesel has gained interest among researchers as an alternative fuel to replace fossil fuels due to its sustainability. Biodiesel can be produced by transesterification of plant oils with methanol using suitable catalysts. Recently, application of heterogeneous catalyst has attracted considerable interest in biodiesel production compared to homogenous catalyst due to their reproducibility. In this study, biodiesel was produced by transesterification of palm oil with methanol catalyzed by calcium oxide coated on alumina beads and doped with nickel. The objective of this study is to determine the optimum catalyst loading of the transesterification process. The catalyst was prepared by heating a mixture of calcium nitrate, nickel(II) nitrate hexahydrate and alumina beads at 700°C. This temperature was selected after performing a thermogravimetric analysis on the calcium nitrate. In this study, the highest yield of 24.24% was obtained from transesterification reaction at optimum conditions of 5 hour reaction time, 1:25 oil-methanol molar ratio and 65°C of reaction temperature with 4 wt% of catalyst loading. Quantification and identification of biodiesel was done using gas chromatography mass spectrometry (GCMS

SURFACE MORPHOLOGY AND CHEMICAL COMPOSITION OF NAPIER GRASS FIBERS (Morfologi Permukaan dan Komposisi Kimia Gentian Rumput Napier)

Abstract A cellulosic component of Napier grass has high potential for the ethanol production. The presence of hemicelluloses, lignin and cellulose in Napier grass fiber can affect the ethanol production. The aim of this study is analyzed the effect of different pretreatment condition (2% of acetic acid and 2% of sodium hydroxide) on the chemical composition and observe the fiber surface morphology of the Napier grass fibers. The fiber surface morphology was observed using Scanning Electrone Microscope (SEM). The result of different pretreatment condition showed that 2% of acetic acid treatment have the highest percentage of cellulose followed by 2% of sodium hydroxide treatment and untreated sample. The hemicellulose content is reduced when treated with acid and alkali. Based on the fiber morphology characterization, acid and alkali pretreatment condition showed that the surface impurities on the fiber were removed. This study suggested that the acid and alkali treatment of Napier grass fibers has a potential to enhance the ethanol production because it can reduce the hemicellulose content. Keywords: Cellulose, Napier grass fiber composition, Pretreatment Abstrak Komponen selulosa dalam rumput Napier mempunyai potensi yang tinggi untuk menghasilkan etanol. Kehadiran hemiselulosa, lignin dan selulosa dalam gentian rumput Napier boleh memberi kesan kepada penghasilan etanol. Objektif kajian ini adalah untuk menganalisa komposisi kimia rumput Napier dalam keadaan pra-rawatan yang berbeza (2% asid asetik dan 2% natrium hidroksida) dan untuk melihat pencirian gentian serat rumput Napier berdasarkan pra-rawatan yang berbeza. Morfologi permukaan gentian dilihat menggunakan Mikroskop Elektron Pengimbas. Keputusan analisa menunjukkan bahawa peratusan selulosa berdasarkan 2% rawatan asid asetik adalah paling tinggi, diikuti gentian yang dirawat dengan 2% natrium hidroksida dan sampel gentian yang tidak dirawat. Kandungan hemiselulosa berkurangan apabila dirawat dengan asid dan alkali. Berdasarkan pencirian morfologi, gentian rumput Napier yang dirawat dengan asid dan alkali mempunyai morfologi permukaan yang lebih licin dan mempunyai banyak ruang di antara gentian. Kajian ini mencadangkan bahawa rawatan asid dan alkali mempunyai potensi untuk menambahkan penghasilan etanol disebabkan berlakunya pengurangan kandungan hemiselulosa

Optical properties of sensitized tin dioxide thin film prepared by using sol-gel spin coating method

Undoped tin dioxide (SnO2)thin films were prepared by sol-gel spin coating process using an alcoholic solution of tin chloride dihydrate (SnCl2.2H2O) as the precursor. The tin dioxide doped terbium (Tb3+) and erbium (Er3+) ion thin films were also prepared using sol gel method in order to form SnO2:Tb3+ and SnO2:Er3+ thin films. The concentration of Tb3+ and Er3+ is 5% in relation with the tin content in the sol. The doped and undoped SnO2 films were sensitized with eosin Y. The diameter of particles in the SnO2 film ranges from 20 to 46 nm with spherical morphology. The particle size of SnO2 doped Tb3+ and SnO2 doped Er3+ thin films are bigger than undoped SnO2 thin films. SnO2 thin films have tetragonal structure with prominent peaks corresponding to (110), (101) and (211) crystal lattice planes. The band gap energy is decreased with the addition of dopant (Tb3+ and Er3+ ion) in sensitized SnO2 thin films. The PL emission peaks of SnO2:Tb3+ sensitized with eosin Y corresponding to the characteristic D?Ftransitions between the energy levels of Tb3+ ion. The addition of erbium (Er3+) to the SnO2 sol results in PL emission peaks that are associated with G?Iand H? I transitions in Er3+ ion

Synthesis of alumina-CaO-KI catalyst for the production of biodiesel from rubber seed oil [Sintesis mangkin alumina-CaO-KI untuk penghasilan biodiesel daripada minyak biji getah]

In this research, biodiesel was produced by transesterification of rubber seed oil with methanol catalyzed by three types of alumina-supported catalyst. The catalysts were Al2O3 -CaO, Al2O3 -KI, and Al2O3 -CaO-KI. The catalysts were prepared by heating a mixture of alumina and the corresponding salt in a furnace at 700 oC. Transesterification reactions were carried out at 65 °C using a mixture of rubber seed oil: methanol of mass ratio 1:9 with different catalyst loadings between 0 and 3.5%. The optimum catalyst loading was at 2.0% for all types of catalyst and Al2O3 -CaO-KI gave the highest yield (91.6%) followed by Al2O3 -KI (90.7%) and Al2O3 -CaO (63.5%). The catalyst Al2O3 -CaO-KI also gave high biodiesel yields over a wider range of catalyst loadings compared to the other two catalysts. Reactions were also carried out at different temperatures (25, 40 and 65°C). It was observed that the yield increased drastically with increasing reaction temperature. At all temperatures the Al2O3 -CaO-KI catalyst gave the highest yield. Therefore, the study showed that among these three catalysts the most productive was Al2O3 -CaO-KI, (100:30:35)

Carboxymethyl-cellulase and filter-paperase activities of napier grass fermentation by new bacterial isolates

Cellulosic biomass is a renewable and most abundant resource with high potential for bioconversion to biofuels. It can be degraded by cellulase produced by cellulolytic producing bacteria. Proximately, three different types of cellulase needed for effective enzymatic hydrolysis; endoglucanase (CMCase), exocellobiohydrolase and β -glucosidase. Total cellulase activity can be determined by measuring reducing sugar derived from filter paper (FPase) while endoglucanase (CMCase) can be determined by measure reducing sugar release from carboxymethyl- cellulose (CMC). In this study, the CMCase and FPase activities of new six isolates from different environments (compost: C5/1 and C5/2; ponds: L5/1, L6/2, and L6/5; and decayed wood: D6/1) were examined according methods recommended by the International Union of Pure and Applied Chemistry (IUPAC).The fermentation has been conducted for 4 days incubation period at 37°C and agitated at 150 rpm. Napier grass has been used as a substrate. As a result, the C5/2 exhibited the highest enzymes activities of CMCase and FPase, which were 2.205U/mL and 0.39U/mL, respectively