Nano-structure Fe2O3, CuO and La2O3 components were prepared by micro-emulsion method and then Fe/Cu/La/SiO2 nano-structure catalyst was prepared by mixing and re-slurring the mixture by tetraethylorthosilicate (TEOS). The catalyst composition was designated in term of the atomic ration as: 100Fe/5.64Cu/0.1La/19Si. Structural characterization of nano-structured Fe2O3, CuO and La2O3 components was performed by Transmission Electron Microscopy (TEM), powder X-ray diffraction, Temperature Programmed Reduction (TPR) techniques. Particle size for obtained components was about 20, 21.6 and 12.6 nm for Fe2O3, CuO and La2O3 respectively determined by using XRD pattern (Scherrer equation) and TEM images. Catalytic activity and product selectivity were conducted in a fixed-bed stainless steel reactor and compared with conventional iron catalyst. The results reveal that reducing particle size of catalyst increased the catalyst performance. Also, olefin/paraffin ratios decreased in comparison with conventional catalyst.

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The esterification of aliphatic and aromatic carboxylic acids with various alcohols (1°, 2°, 3°, benzylic) was studied under microwave irradiation in the presence of zinc triflate as catalyst; the reaction times were short and the yield of reactions was good to excellent.

The sol–gel method is employed for producing high surface area silica nanoparticles from a cheap precursor, that is water glass (sodium silicate). To design the experiments systematically, the response surface method (RSM) combined with the central composite design (CCD) approach is used. Four major factors including the concentration of sodium silicate solution, solution pH, reaction temperature and reaction time are identified as the major controlling parameters and the particle surface area is considered as the response or the output parameter. A total of 31 experiments are designated by the CCD. The experiments are conducted at a centre point chosen based on experience and at its vicinity to investigate how the response changes as the factors change. Nanoparticles with a surface area as high as 630 m2/g and a particle size as low as 8 nm are produced at the optimum parameters of sodium silicate concentration of 1.5 × 10−4 g/L, pH of 4, a reaction temperature of 25°C and a reaction time of 1.5 h. A regression analysis is performed on the experimental data and a correlation is obtained that may be used to predict the particle surface area and investigate the effect of varying the factors on the response. Within the range of parameters studied here, it is found that the solution pH and then the process temperature have a profound effect on the surface area and concentration and reaction time have a moderate effect. An increase of the solution pH from 4 to higher values results in a rapid drop in the particle surface area.