Universiti Teknologi Petronas

About: Universiti Teknologi Petronas is a education organization based out in Ipoh, Malaysia. It is known for research contribution in the topics: Adsorption & Ionic liquid. The organization has 6127 authors who have published 11284 publications receiving 119400 citations.

Effects of torrefaction on the physiochemical properties of oil palm empty fruit bunches, mesocarp fiber and kernel shell.

Abstract: In this work, the effects of torrefaction on the physiochemical properties of empty fruit bunches (EFB), palm mesocarp fiber (PMF) and palm kernel shell (PKS) are investigated. The change of properties of these biomass residues such as CHNS mass fraction, gross calorific value (GCV), mass and energy yields and surface structure when subjected to torrefaction process are studied. In this work, these materials with particle size in the range of 355–500 μm are torrefied under light torrefaction conditions (200, 220 and 240 °C) and severe torrefaction conditions (260, 280 and 300 °C). TGA is used to monitor the mass loss during torrefaction while tube furnace is used to produce significant amount of products for chemical analyses. In general, the study reveals torrefaction process of palm oil biomass can be divided into two main stages through the observation on the mass loss distribution. The first stage is the dehydration process at the temperature below than 105 °C where the mass loss is in the range of 3–5%. In the second stage, the decomposition reaction takes place at temperature of 200–300 °C. Furthermore, the study reveals that carbon mass fraction and gross calorific value (GCV) increase with the increase of torrefaction temperature but the O/C ratio, hydrogen and oxygen mass fractions decrease for all biomass. Among the biomass, torrefied PKS has the highest carbon mass fraction of 55.6% when torrefied at 300 °C while PMF has the highest GCV of 23.73 MJ kg−1 when torrefied at the same temperature. Both EFB and PMF produce lower mass fraction than PKS when subjected to same torrefaction temperature. In terms of energy yield, PKS produces 86–92% yield when torrefied at light to severe torrefaction conditions, until 280 °C. However, both EFB and PMF only produce 70–78% yield at light torrefaction conditions, until 240 °C. Overall, the mass loss of 45–55% of these biomasses is observed when subjected to torrefaction process. Moreover, SEM images reveal that torrefaction has more severe impact on surface structure of EFB and PMF than that of PKS especially under severe torrefaction conditions. The study concludes that the torrefaction process of these biomass has to be optimized based on the type of the biomass in order to offset the mass loss of these materials through the process and increase the energy value of the solid product.

Hybrid carbon fiber-carbon nanotubes reinforced polymer composites: A review

Abstract: As a result of its impressive 3D network structure form, a great deal of interest has thus been generated among the science community on the hybridization of carbon fiber (CF) and carbon nanotube (CNT). Although there had been a large amount of studies conducted on this novel hybrid material, there are however, limited reviews being published on their fabrication methods and performances in polymer composites. For this reason, apart from collectively introducing and discussing the advantages and limitations of the hybrid CF-CNT based on various fabrication methods such as those of chemical vapour deposition, electrophoretic deposition, electrospray deposition and chemical functionalization, this study had also examined and compared the detailed performances of each of the hybrid CF-CNT reinforced polymer composite based on their fabrication methods through its mechanical, electrical and thermal properties.

Catalytic hydrodeoxygenation of triglycerides: An approach to clean diesel fuel production

Abstract: The catalytic upgrading of vegetable oil to green diesel is one of the distinct research subjects in biorefineries. The catalytic conversion of triglycerides entails the method of hydrotreating such as hydrogenation, hydrodeoxygenation, decarboxylation and decarbonylation as well as isomerization. The product derived is renewable green diesel (straight chain hydrocarbon), of which its production addresses the sustainability of the future energy. The main challenges faced by hydrodeoxygenation are the selection and synthesis of suitable catalysts, selection of appropriate feedstocks, optimization of the thermodynamic parameters, and the reaction pathways. The literature on the selection of feedstock and model compounds is discussed in the sub-section. This review also includes the evaluation on several potential catalysts such as bimetallic solid acid, sulphided, non-sulphided, nitrides, phosphided, isomerization and hydrocracking catalysts as well as the noble metal catalysts. The selection of the metal supports catalysts, the catalyst designed practice and the overall performance is also reviewed and discussed. The most common supports used for the hydrodeoxygenation is solid acid composites such as Al 2 O 3 and zeolites. In addition, the promoters tested yield different results with different reaction mechanisms demonstrated. The research on the hydrodeoxygenation pathways and the product distribution related with all kinds of catalysts are also addressed. In addition, the advancement of co-hydroprocessing of mix-vegetable oil and vacuumed gas oil is addressed and summarized as well. Overall, this review provides a comprehensive discussion on the hydrodeoxygenation issues and challenges in all relevant technical aspects.