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Andalusite, as a refractory material, transforms to mullite and a silica rich liquid phase at 1100-1600uC. The glassy phase constitutes about 20 wt-% of the reaction products, which is undesirable in refractories. In this research, alumina and zirconia were added to andalusite in order to reduce the amount of the glassy phase. Alumina was introduced by dry and solution mixing, while zirconia was added only by dry mixing method. The effects of MgO on andalusitemullite and andalusite-zirconia mixes were also studied. MgO was introduced by solution (precipitation) method on andalusite surface. The samples were fired at 1400, 1500 and 1600uC. X-ray diffraction and SEM results showed that alumina reduces the liquid phase at all of the temperatures, but zirconia was effective only at 1400 and 1500uC. MgO seemed to be capable of reducing in andalusite transformation by 100uC and had positive effect on reaction between alumina and liquid phase; it was not effective on reaction between zirconia and liquid phase.

AB STRACT: (Lanthanum, Cerium)(Iron, Manganese, Cobalt, Palladium)(Oxygen) 3 -Perovskite catalyst was prepared by the citrate route and deposited on ceramic monoliths via dip coating procedure. The catalyst was applied on a car with XU7 motors and the amount of emission was monitored with vehicle emission test systems in Sapco company. The results were compared with the imported catalyst with noble metals such as palladium, platinum and rhodium by Iran Khodro company based on the Euro III standards. The catalysts were characterized by specific surface area measurements, scanning electron microscopy, X-ray diffraction, line scan and map. In the results, obtained in the home made sample, the amount of carbon monoxide, nitrogen oxides and hydrocarbons were lower than imported catalyst with Iran Khodro company with nobel metals. The illustration shows nano particles size on coat. The microstructure evaluation showed that the improved properties can be related to the existence of nano particles on coating.

Mesoporous carbon CMK-3 was synthesized by using SBA-15 silica mesoporous as hard template and characterized through nitrogen adsorption/desorption and low angle X-ray diffraction. As-prepared material with large pores and high surface area was used to remove Orange G dye from aqueous solution. Adsorption experiments were carried out as batch studies at variety of contact times, pH, initial dye concentrations, temperatures and salt concentrations. Langmuir and Freundlich isotherm models were employed to simulate the equilibrium data of anionic dye. It was found that the equilibrium data were well represented by the Langmuir isotherm, yielding maximum monolayer adsorption capacity of 189 mg/g. Experimental data were analyzed using pseudo-first order and pseudo-second order kinetic models and obtained results indicated that kinetics followed a pseudo-second order equation.

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