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Catalytic pyrolysis experiments have been carried out on Brunei Rice Husk (BRH) to obtain bio-oil using a fixed-bed pyrolysis rig. ZSM-5, Al-MCM-41, Al-MSU-F and Brunei rice husk ash (BRHA) were used as the catalysts for the catalytic pyrolysis experiments and comparison was done to analyse the changes in the bio-oil properties and yield. Properties of the liquid catalytic and non-catalytic bio-oil were analysed in terms of water content, pH, acid number, viscosity, density and calorific value. The bio-oil chemical composition shows that ZSM-5 increases the production of aromatic hydrocarbons and light phenols, whilst Al-MCM-41 reduces the acetic acid production. The catalytic runs increased the calorific value and water content in the bio-oil, whilst viscosity, density and acid number is decreased.

The interlayer pores of swelling 2:1 clays provide an ideal 2-dimensional environment in which to study confined fluids. In this paper we discuss our understanding of the structure and dynamics of interlayer fluid species in expanded clays, based primarily on the outcome of recent molecular modelling and neutron scattering studies. Counterion solvation is compared with that measured in bulk solutions, and at a local level the cation-oxygen coordination is found to be remarkably similar in these two environments.However, for the monovalent ions the contribution to the first coordination shell from the clay surfaces increases with counterion radius. This gives rise to inner-sphere (surface)

Theoretical methods are used to study the adsorption of linear hydrocarbons, C1-C8, in silicalite, H-ZSM-5, and siliceous faujasite. The aim is to model the behavior of sorbed species in zeolites and evaluate the influence of the zeolite structure and composition on the sorption process. The method of calculation is energy minimization using the Born model of solids with specified interatomic potentials. Atom-atom potentials are used to model the zeolite and zeolite-hydrocarbon interactions. The effect of relaxation both of the zeolite framework and of the molecule is investigated. The location of adsorption sites and heats of adsorption for the molecules are presented. The sorption process is controlled by the shape and volume of the available cavity and the packing ability of the molecule concerned. In silicalite and H-ZSM-5, adsorption at the straight channel is preferred to that of sinusoidal channel. The simulations show the extent to which hydrocarbons sorb more strongly in ZSM-5 zeolites than in siliceous faujasites.