Jidon Janaun

Development of sulfonated carbon catalysts for integrated biodiesel production

........................................................................................................................................... ii Preface ............................................................................................................................................. iii Table of contents............................................................................................................................... v List of tables .................................................................................................................................. viii List of figures ................................................................................................................................... x Nomenclature ..................................................................................................................................xv Abbreviations ............................................................................................................................... xvii Acknowledgements ..........................................................................................................................xx Dedication .................................................................................................................................... xxii Chapter

Synthesis, characterization and catalytic activity of carbon-silica hybrid catalyst from rice straw

The hybrid-carbon catalyst has been studied because of its promising potential to have high porosity and surface area to be used in biodiesel production. Silica has been used as the support to produce hybrid carbon catalyst due to its mesoporous structure and high surface area properties. The chemical synthesis of silica-carbon hybrid is expensive and involves more complicated preparation steps. The presence of natural silica in rice plants especially rice husk has received much attention in research because of the potential as a source for solid acid catalyst synthesis. But study on rice straw, which is available abundantly as agricultural waste is limited. In this study, rice straw undergone pyrolysis and functionalized using fuming sulphuric acid to anchor –SO3H groups. The presence of silica and the physiochemical properties of the catalyst produced were studied before and after sulphonation. The catalytic activity of hybrid carbon silica acid catalyst, (H-CSAC) in esterification of oleic acid with me...

Synthesis and characterization of supported sugar catalyst by dip coating method

Sugar catalyst is a novel solid acid catalyst with reactivity comparable to that of sulphuric acid in biodiesel production. However, the fine powder form of sugar catalyst with the non-porous structure might cause large pressure drop in a packed bed reactor due to low bed porosity, affecting the reaction conversion especially in gas phase reaction. Furthermore, higher pressure drop requires higher electrical energy to drive the fluid through. Increasing the particle size is anticipated to be able to overcome the pressure drop matter. Hence, a deposition of sugar catalyst on larger particle materials was studied. Three types of materials were used for this investigation namely aluminum, silica and clay. The deposition was done via dip-coating method. The materials were characterized for their total acidity, thermal stability, functional groups, surface area, and element composition. The total acidity for SCDCAl, SCDCSi, and SCDCCl were 0.9 mmol/g, 0.2 mmol/g, and 0.4 mmol/g, respectively. The ratio of char deposited on SCDCAl, SCDCSi and SCDCCl were 0.9 g of support/g of carbon, 0.040 g of support/g of carbon, and 0.014 g of support/g of carbon respectively. FTIR and EDX analyses were carried out to determine the presence of active sites of the catalysis by identifying the functional groups such as -COOH, -OH, -SO3H. The results showed that -SO3H was detected on the surface of synthesized catalysts, except for SCDCC1.The pore size of SCDCAl, SCDCSi and SCDCCl were classified as macropores because the average diameter were greater than 50nm.. The catalysts were stable up to 400°C. The results showed that the dipcoating method could deposit sugar catalyst on aluminum, silica, and clay at low total acidity concentration.

β-Mannanase Production by Aspergillus flavus in Solid-State Fermentation of Palm Kernel Cake

β-Mannanase production in batch solid-state fermentation (SSF) of palm kernel cake (PKC) was evaluated with flasks and a laterally aerated moving bed (LAMB) bioreactor using Aspergillus flavus UMS01. Optimum condition for flask SSF was 110 % moisture content, initial pH 6, 30 °C and particle size 855 μm, yielding 383 U g−1 dry PKC after 120 h. Under the same condition and particle size <5 mm, SSF in LAMB produced 276 U g−1 dry PKC at an optimal gas flow of 4.4 m s−1 in just 96 h. Optimal β-mannanase production was consistent with highest fungal growth and mannose production; to support increasing fungal growth, secretion of β-mannanase increased to degrade mannans in PKC, producing mannose for microbial consumption. A. flavus UMS01 showed promising attributes as a β-mannanase producer via SSF of PKC in flasks and LAMB bioreactor.

Dynamic Adsorption of Water Vapour by Palm Kernel Cake

Dynamic water vapour adsorption isotherms by palm kernel cake in a packed bed column were determined at different relative humidity of air (20–95 ± 2%), superficial air velocity (0.05–0.15 m/s), constant ambient temperature (30 ± 1°C), and bed height, and with dried palm kernel cake of different particle sizes (0.86–5.15 mm). The isotherms were affected by the relative humidity, superficial velocity, and particle size, followed Brunauer-Emmett-Teller Type III classification, and fitted satisfactorily with the Freundlich equation. The maximum water adsorbed was less than 20%. This indicated that in the solid-state fermentation of palm kernel cake, where forced aeration was employed, the use of humidified air was inadequate in maintaining bed moisture level.