Influence of fatty acids content in non-edible oil for biodiesel properties

Physical and chemical properties of biodiesel are influenced by the structural features of fatty acid, such as with saturated, monounsaturated and polyunsaturated fatty acids. In this study, seven non-edible oils have been selected, which include waste cooking oil derived palm olein, Calophyllum inophyllum, jatropha oil, castor oil, rubber seed oil, kapok seed oil and karanja oil. The critical parameters, e.g. cetane number (CN), iodine value (IV) and oxidation stability (OS) of biodiesel were correlated with the degree of unsaturated (DU) fatty acid, whereas the cold filter plugging point (CFPP) was correlated with the long chain saturated factor (LCSF). To meet the minimum EU requirement of EN 14214 of the critical parameter, the DU value of the CN was ≤133.5, IV ≤123.2 and OS ≤98.9. The LCSF values satisfied the Spanish regional standard—RD 61/2006 in summer (0 °C) at ≤8.4 and winter (?10 °C) at ≤0.1 of the CFPP. Based on the composition of the saturated, monounsaturated and polyunsaturated fatty acids, a triangular chart for the biodiesel property prediction was developed. This can then be used as a reference for non-edible oils.     

Comparative life cycle assessment (LCA) of bio-oil production from fast pyrolysis and hydrothermal liquefaction of oil palm empty fruit bunch (EFB)

This paper presents a life cycle assessment of two alternative processes for the production of bio-oil from Malaysian oil palm empty fruit bunch (EFB), namely, fast pyrolysis and hydrothermal liquefaction, in which limited studies have been reported in the literature. In this study, both processes were evaluated and compared in terms of their impacts to the environment, specifically based on the selected impact categories: global warming potential (GWP), acidification, eutrophication, toxicity, and photochemical-oxidant formation. The results indicated that fast pyrolysis process of EFB caused more severe impact on the environment compared to hydrothermal liquefaction process. Fast pyrolysis process caused almost 50 % more GWP impact compared to hydrothermal liquefaction process, due to both high energy demand in the drying process and high-temperature operation of fast pyrolysis. Other than that, the assessment on other environmental impacts indicated that hydrothermal liquefaction operation is more environmentally benign compared to fast pyrolysis due to the reduced energy consumption. Lastly, sensitivity analysis involving three scenarios (change in bio-oil yield, thermal efficiency of boilers, and thermal efficiency of dryers), respectively, were constructed and presented.     

Particulate composites based on ionic liquid-treated oil palm fiber and thermoplastic starch adhesive

Pretreatment of lignocellulosic materials is a highly essential and critical task for the manufacturing of engineered composite panels. Recently, ionic liquids (ILs) have emerged as a promising green solvent for lignocellulosic biomass disintegration. In this work, the impact of IL pretreatment on the flexural and thermal properties of the thermo-molded biocomposite panels made from oil palm biomass residue and thermoplastic starch biopolymer as binder was studied. Oil palm fiber was pretreated with IL [emim][dep] (1-ethyl-3-methylimidazolium diethyl phosphate) and IL [bmim][Cl] (1-butyl-3-methylimidazolium chloride) prior to mixing with plasticized starch. The compounded mixture was then hot-pressed into composite panels. To understand the effect of IL pretreatment, lignocellulosic characterization, morphology, and thermogravimetric analysis of the untreated and treated fibers were performed. It was found that thermal stability of the oil palm biomass and the biocomposites was improved after IL pretreatment due to partial removal of hemicellulose and lignin from raw fiber. Moreover, pretreated biocomposites exhibited superior strength and modulus as compared to that of untreated sample as evidenced from flexural testing. The study plainly demonstrates that IL-assisted pretreatment could be an extremely attractive and clean technology for the efficient use of agro-based industrial waste in biocomposite field.     

Process simulation of hydrogen production from bio-oil using iCON

This work aims to investigate the feasibility of upgrading bio-oil into hydrogen via steam reforming and water shift reactions using conceptual design and simulation approaches. In the simulation work using PETRONAS iCON software, it is assumed that the aqueous fraction of bio-oil comprises of 67% acetic acid, 16.5% acetone, and 16.5% ethylene glycol. It is observed that increment in temperature and the amount of steam supplied in the steam reformer increase the hydrogen production until a certain extent. Meanwhile, opposite effect on hydrogen production is observed for both the temperature and steam used in the shift reactor. The overall conversion predicted for the process is 84% at operating temperatures and pressures for the steam reformer and shift reactor of 650 and 200°C, and 1 and 17 bar, respectively, and at the molar steam-to-carbon ratio (S:C) of 6.5. The results are compared and showed good agreement with those from published simulation and experimental work. Positive preliminary economic potential was obtained for the process developed, that is, USD 5.56 × 10⁶/year.     

Effects of plasticizers on the properties of oat starch films

Oat starch films were prepared by casting using glycerol, sorbitol, glycerol–sorbitol mixture, urea and sucrose as plasticizers. The effects of these plasticizers on the microstructure, moisture sorption, water vapor permeability (WVP) and mechanical properties were investigated using films stored under a range of relative humidities. The plasticizer type did not affect significantly (p ≤ 0.05) the equilibrium moisture content of films, except at 90% relative humidity (RH). Films without plasticizer adsorbed less water and showed higher WVP than plasticized ones, indicating the antiplasticizing effect observed in this work. In general, a decrease in stress at break and Young's modulus and an increase in strain at break were observed when RH increased in all film formulations. Films without plasticizer showed higher stress at break values than the plasticized ones and presented stable strain at break under a range of RH. Sucrose films were the most fragile at low RH while glycerol films were the most hygroscopic.     

Energy efficiency technologies for road vehicles

A key message of the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change is that improved energy efficiency is one of society’s most important instruments for combating climate change. This article reviews a range of energy efficiency measures in the transportation sector as discussed in AR4 and assess their potentials for improving fuel efficiency. The primary focus is on light-duty vehicles because they represent the largest portion of world transport energy use and carbon dioxide emissions; freight trucks, a rapidly expanding source of greenhouse emissions, are also discussed. Increasing energy efficiency can be achieved by improving the design and technology used in new vehicles, but vehicle technology is only one component of fleet fuel economy. Measures that create strong incentives for customers to take energy efficiency into consideration when buying and operating their vehicles will be crucial to policy success.

Liquefaction of palm kernel shell to bio-oil using sub- and supercritical water: An overall kinetic study

Palm kernel shell was liquefied using sub- and supercritical water at 330–390 °C and 25 MPa for different reaction times. The overall kinetics of the liquefaction based on the conversion of biomass was analyzed using kinetic equation adopted from the literature, and the kinetic parameters were estimated from the evaluation of the kinetic equation. In this study, the rate constant (k) increased from 0.43 to 0.49 s^?1 with reaction temperature from 330 to 390 °C. The relationship of rate constant (k) and temperature agreed reasonably well with the Arrhenius equation. The activation energy (E) and pre-exponential factor (A) values for the liquefaction process were estimated to be 6.70 kJ/mol and 1.65 s^?1, respectively. In addition, the experimental bio-oil yields with respect to reaction time were well-fitted using the modified Reverchon-Sesti Osseo equation.     

Influence of the agitation rate on the treatment of partially soluble wastewater in anaerobic sequencing batch biofilm reactor

This work reports on the influence of the agitation rate on the organic matter degradation in an anaerobic sequencing batch reactor, containing biomass immobilized on 3 cm cubic polyurethane matrices, stirred mechanically and fed with partially soluble soymilk substrate with mean chemical oxygen demand (COD) of 974+/-70 mg l(-1). Hydrodynamic studies informed on the homogenization time under agitagion rates from 500 to 1100 rpm provided by three propeller impellers. It occurred very quickly compared to the total cycle time. The results showed that agitation provided good mixing and improved the overall organic matter consumption rates. A modified first-order kinetic model represented adequately the data in the entire range of agitation rate. The apparent first-order kinetic constant for suspended COD rose approximately 360% when the agitation rate was changed from 500 to 900 rpm, whereas the apparent first-order kinetic constant for soluble COD did not vary significantly.