Supported CaO/MgO catalysts were used as the catalyst of the transesterification of rapeseed oil with methanol. The supported catalyst showed a higher activity than pure CaO and was easily separated from the product mixture. The results of comparative experiments and catalyst characterization, such as XRD, CO2-TPD, BET, and AAS, showed that the activity of CaO catalysts is associated with their alkalinity. The preparation method of this catalyst was optimized, and furthermore, the reaction parameters were investigated. With the CaO/MgO catalyst so obtained, the conversion of rapeseed oil reached 92% at 64.5 °C. The supported basic catalyst was found to be easily contaminated by the gaseous poisons in air, such as O2, CO2, and H2O, and as a result, a thermal treatment was required before the reaction to activate the catalyst.

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Anti-scaling technology is necessary in order to prevent the performance loss and blockage of heat-exchanger. In this research, a superhydrophobic CuO nanowire layer was prepared and utilized for anti-scaling process of CaCO 3 on the surface of copper.Modified with 1H,1H,2H,2H-perfluorooctyltriethoxy-silanen (FAS-17) the water contact angle on the CuO surface increased sharply from the 4.5±1° after anodization to 154±2° since the free surface energy decreased from 74.8 mJ/m 2 of hydrophilic surface to 0.2 mJ/m 2 of superhydrophobic surface. The scale inhibition performance of superhydrophobic CuO nanowires surface was confirmed since the corresponding scaling weight of deposited CaCO 3 decreased significantly from 0.6322 mg/cm 2 to 0.1607 mg/cm 2 . This attractive anti-scaling effect of modified superhydrophobic CuO nanowires surface should ascribe to the slow CaCO 3 crystal nucleation rate due to the low surface energy, low adhesion strength of CaCO 3 crystal and air film retained on the superhydrophobic surface.

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