Amin Talebian-Kiakalaieh

Microwave assisted biodiesel production from Jatropha curcas L. seed by two-step in situ process: Optimization using response surface methodology

The synthesis of fatty acid ethyl esters (FAEEs) by a two-step in situ (reactive) esterification/transesterification from Jatropha curcas L. (JCL) seeds using microwave system has been investigated. Free fatty acid was reduced from 14% to less than 1% in the first step using H2SO4 as acid catalyst after 35 min of microwave irradiation heating. The organic phase in the first step was subjected to a second reaction by adding 5 N KOH in ethanol as the basic catalyst. Response surface methodology (RSM) based on central composite design (CCD) was utilized to design the experiments and analyze the influence of process variables (particles seed size, time of irradiation, agitation speed and catalyst loading) on conversion of triglycerides (TGs) in the second step. The highest triglycerides conversion to fatty acid ethyl esters (FAEEs) was 97.29% at the optimum conditions:<0.5mm seed size, 12.21 min irradiation time, 8.15 ml KOH catalyst loading and 331.52 rpm agitation speed in the 110 W microwave power system.

容碳的SiW 20 -Al/Zr 10 催化剂用于甘油脱水制丙烯醛

Glycerol dehydration to acrolein over a series of supported silicotungstic acid catalysts (SiWx-Al/Zry) was investigated. Characterization results showed that the final catalyst had high thermal stability, a large pore diameter, strong Lewis acidic sites, and a large specific surface area. X-ray photoelectron survey spectra clearly showed peaks attributable to W (W 4f = 35.8 eV), Al2O3 (Al 2p = 74.9 eV), and ZrO2 (Zr 3d = 182.8 eV). The highest acrolein selectivity achieved was 87.3% at 97% glycerol conversion over the SiW20-Al/Zr10 catalyst. The prepared catalysts were highly active and selective for acrolein formation even after 40 h because of the presence of high concentrations of Lewis acidic sites, which significantly reduced the amount of coke on the catalyst surface. Response surface methodology optimization showed that 87.7% acrolein selectivity at 97.0% glycerol conversion could be obtained under the following optimal reaction conditions: 0.5 wt% catalyst, reaction temperature 300 °C, and feed glycerol concentration 10 wt%. Evaluation of a mass-transfer-limited regime showed the absence of internal and external diffusions over pellets of diameter dP < 20 μm. These results show that glycerol dehydration over a strong Lewis acid catalyst is a promising method for acrolein production.

Single and Two-Step Homogeneous Catalyzed Transesterification of Waste Cooking Oil: Optimization by Response Surface Methodology

Large number of studies related to alkali and acid catalyzed transesterification of waste cooking oil are widely available, but references for optimization and modeling comparison between single and two-step transesterification are scarce. Therefore, response surface methodology (RSM) has been employed to study the relationship between process variables and predict the optimal conditions. Sulfuric acid and sodium hydroxide were utilized in the pretreatment step and alkali catalyzed transesterification reaction, respectively. The highest free fatty acid (FFA) conversion in the two- and single-step reactions was 93.8% and 82.7%, respectively at the optimal reaction conditions being 1.1 wt% catalyst loading, 6.5:1 methanol to oil ratio, 60°C reaction temperature, and 65 min reaction time. .RSM could accurately predict the optimal FFA conversion in both two- and single-step processes by only 0.3% and 1.01% error, respectively. In addition, the two-step method produced higher fatty acid methyl ester (FAME) yield (86.7%) and also improved the final product quality compared to single-step method with only 73.7% biodiesel yield.

Reduction of CO 2 emission by INCAM model in Malaysia biomass power plants during the year 2016

As the worlds second largest palm oil producer and exporter, Malaysia could capitalize on its oil palm biomass waste for power generation. The emission factors from this renewable energy source are far lower than that of fossil fuels. This study applies an integrated carbon accounting and mitigation (INCAM) model to calculate the amount of CO2 emissions from two biomass thermal power plants. The CO2 emissions released from biomass plants utilizing empty fruit bunch (EFB) and palm oil mill effluent (POME), as alternative fuels for powering steam and gas turbines, were determined using the INCAM model. Each section emitting CO2 in the power plant, known as the carbon accounting center (CAC), was measured for its carbon profile (CP) and carbon index (CI). The carbon performance indicator (CPI) included electricity, fuel and water consumption, solid waste and waste-water generation. The carbon emission index (CEI) and carbon emission profile (CEP), based on the total monthly carbon production, were determined across the CPI. Various innovative strategies resulted in a 20%-90% reduction of CO2 emissions. The implementation of reduction strategies significantly reduced the CO2 emission levels. Based on the model, utilization of EFB and POME in the facilities could significantly reduce the CO2 emissions and increase the potential for waste to energy initiatives.

Penyahhidratan gliserol fasa gas kepada akrolein menggunakan sokongan mangkin asid silikotungstik

Due to the various environmental concerns, a steep hike in fossil fuel price and an increasing demand of non-renewable fossil fuels consumption, the bio-basedgas-phase dehydration of glycerol to acrolein has attracted much attention recently.Thus, the gas phase dehydration of glycerol to acrolein over two groups of supported silicotungstic acid on aluminum oxide (Al2O3) nanoparticle and zirconium dioxide catalyst is being investigated in this study. The catalysts were characterized by, Xraydiffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy and energy dispersive X-ray techniques, temperature programmed desorption, thermogravimetric analysis, and elemental analyzer. The characterization results revealed that Al2O3 nano particle loading increased thermal stability, pore diameter, and specific surface area of the synthesized catalysts.Optimization by response surface methodology revealed the highest acrolein selectivity of 88.5% at 97% glycerol conversion was obtained over 30HZ-20Acatalyst with turnover frequency being 136 h-1 in 3 h for glycerol feed concentration of 10.3 wt% and 0.5 g catalyst at 300 ˚C. Coke deposition has no significant effect on the catalyst activity due to the large catalyst pore diameter (> 27 nm). The prepared catalysts were highly active and selective for acrolein production even after 40 h without any needs for gas co-feeding or application of noble metals. In addition, the kinetic study results demonstrated that glycerol dehydration to acrolein followed first-order rate with the activation energy (Ea) of 27.5 kJ/mol and frequency factor(A) of 5.35×105 s-1. Finally, the theoretical and experimental approaches confirmed no internal mass transfer limitation in glycerol dehydration reaction with catalyst pellet sizes of dp= 2-4 and 5-7 μm due to effectiveness factor equal to 1 (η=1).Calculation of the overall effectiveness factor (Ω) also confirmed the absence of external diffusion in presence of catalysts with pellet size of dp< 7 μm

Kinetic Study on Catalytic Conversion of Glycerol to Renewable Acrolein

Biodiesel is a suitable alternative to gasoline and diesel since it emits less carbon emission. There has been a surplus of glycerol in the market due to biodiesel production. Glycerol may be a good source of bio-based feed since it is from a renewable source. The kinetic study of gas-phase glycerol dehydration reaction using a supported ?-Al2O3 nanoparticle based solid heteropoly acid catalyst (SiW20-Al/Zr10) has been investigated. A kinetic model was established, based on the reaction mechanism, taking into account two parallel reactions of glycerol degradation into acrolein or acetol. All the reaction rate constants and activation energies were determined at various reaction temperatures (280 – 340 °C). The first-order kinetic model and the experimental data fitted-well. Results revealed that all the rate constants increased with temperature, and the activation energies of glycerol dehydration to acrolein and acetol were 46.0 and 53.3 kJ/mol. The results from this study are useful for simulation and process modelling of a bio-refinery for sustainable production of bio- based chemicals.