KOH-catalyzed synthesis of biodiesel was carried out in capillary microreactors with inner diameters of 0.25 or 0.53 mm, with unrefined rapeseed oil and cottonseed oil as raw materials. The influences of the methanol to oil molar ratio, the residence time, the catalyst concentration, the reaction temperature, and the dimension of the capillary on the production of biodiesel were examined. The results indicated that the residence time was greatly reduced by using microchannel reactors, compared with a conventional batch reactor. The reaction temperature was the minimal factor in the yield of methyl ester. Meanwhile, the methyl ester yield first increased with the methanol/oil ratio and then decreased due to emulsion and saponification. The inner diameter of the microchannel reactor had a strong influence on the transesterification reaction. Higher methyl ester yield could be obtained at shorter residence times for the microchannel reactor with the smaller inner diameter.

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Silicalite nanocrystals were synthesized in a pressurized capillary microreactor at 150°C within 11 min with synthesis solutions aged at 80 or 100°C for 1-6 h. The effects of aging of the synthesis solution and the reaction pressure were examined. The resulting products were characterized by XRD, DLS, TEM, FT-IR and TG-DSC. Aging of the synthesis solution played an important role in shortening the crystallization time of the silicalites. The synthesis pressure should be higher than the saturation vapor pressure of water at 150°C (∼0.5 MPa) and silicalite nanocrystals with crystallinities of 70 % and 100 % could be produced from the synthesis solution aged at 100°C for 2 h with residence times of 11 min at 0.7 MPa and 1 MPa, respectively. The mean particle sizes of these two samples were 102.2 nm and 166.4 nm, respectively. Thus, the crystallization time of the silicalite nanocrystals is shown to be significantly reduced in the capillary microreactor compared to a traditional batch system.

2014) Syntheses and structural characterization of six ionic salts based on bis(benzimidazole)/bis(imidazole) and perchlorometallates of Due to the weak interactions, the compound displays 3-D layer structure. Six salts, ([(H 2 L1)(ZnCl 4 )] (1) (L1 = 1,1′-bis(benzimidazolyl)methane), [(H 2 L1)(CuCl 4 )]·H 2 O (2), [(H 2 L2)(ZnCl 4 )] (3) (6) (L4 = 3,6-bis(imidazol-1-yl)pyridazine)), derived from bis(benzimidazole)/ bis(imidazole) and metal(II) chloride dihydrate (zinc(II) chloride and copper(II) chloride dihydrate) were prepared and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The aromatic rings of the cations in all of the compounds are planar. X-ray diffraction analysis revealed that all the complexes have 3-D layer network structures built from hydrogen bonds between the cations and chlorometallate anions. Water molecules also play an important role in structure extension in 2, 5, and 6. The arrangements of the anions and cations in their solid state are dominated not only by size and symmetry of the cations, but also by the non-covalent interactions existing in the crystal structures.

Pd-B amorphous alloy was successfully supported on the surface of natural nanoclay palygorskite (PAL) via a simple chemical reduction method. Compared with the conventional supported Pd catalyst, the Pd-B/PAL amorphous catalyst possessed the ultra-high selectivity (100%) to o-chloroaniline (o-CAN) in the hydrogenation of o-chloronitrobenzene (o-CNB) to o-CAN and avoided the dechlorination of o-CNB. XPS analysis results indicated that PAL support could reduce the electron density of Pd atoms and suppressed the hydrogenolysis of C-Cl bond. Meanwhile, the Pd-B/PAL amorphous catalyst exhibited a good stability and is a prospective catalyst for the selective hydrogenation of CNB to CAN.