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In this research, methyl acrylate has been synthesized from industrial raw material methyl acetate through highly efficient and eco-friendly method, One-step aldol condensation, using acid-base bifunctional catalyst Cs, P and K as catalysts. Carbon deposits and other issues led to the catalysts deactivation in the process of fixed bed, which led to the production interruption. While, the process of circulating fluidized bed can overcome this defect and the catalyst can maintain good catalytic activity in the whole process. Cs (8%), P (5%), K (2%)/γ-Al2O3/ catalyst showed better performance due to its high surface area and more weak basicity and acidity. In addition, theoretical calculations and cold model experiments were also conducted in this work to determine the catalyst particle size，operation gas velocity and gas distributor plate.

The effect of gel formation on the mass transfer of water during evaporation or condensation from MgSO4 droplets is studied using aerosol optical tweezers coupled with Raman spectroscopy. In particular, the kinetics of water transport during hydration and dehydration are followed for variable step changes in relative humidity and compared with previous measurements using different methodologies. Slow diffusion of water in the particle bulk is shown to limit water evaporation and condensation from the aerosol. Desorption of water continues over a long time at the very low RH region and this is validated with complementary studies made by FTIR-ATR and measurements of water adsorption isotherms. The observations can be rationalized when considering the possible phase transformation of the gel structure at very low RHs. Finally, the influence of the duration of the drying time (RH ≤ 10%) on the kinetics of condensation during hydration is investigated. Apparent diffusion coefficients of water molecules in the gel are obtained, showing little dependence on the water activity and droplet composition, and are consistent with the slow removal of water during drying from pores formed at the gel transition RH.

The FTIR-ATR spectra of Na 2 SO 4 and mixed Na 2 SO 4 /glycerol (1:1) aerosols are monitored in the dehumidifying and humidifying process. It shows that glycerol suppresses both heterogeneous and homogeneous nucleation of Na 2 SO 4 /glycerol aerosols on the ZnSe substrate, while the water uptake of surrounding glycerol leads to lower deliquescence relative humidity of mixed Na 2 SO 4 /glycerol aerosols. In mixed Na 2 SO 4 /glycerol aerosols, glycerol restrains the formation of contact ion pairs between Na + and SO 4 2− , resulting in the delay of the efflorescence relative humidity. And glycerol molecular conformations transform from γγ to αα type in the dehumidifying process.