•Silica-walled TS-1 colloidosomes were fabricated through an interfacial sol-gel process.•Micron-sized TS-1 colloidosome can be easily recycled by a filtration process.•The prepared TS-1 colloidosome dimension is tailorable according to water-to-oil volume ratio (Rw/o) and ratio of TS-1 wt to oil volume (Rs/o).•The prepared TS-1 colloidosome is catalytically active for liquid-phase alkene epoxidation.Ultrafine hierarchical TS-1 zeolite (<300 nm) generally expresses eminent catalytic activity for liquid-phase alkene epoxidation, but encounters serious separation difficulties. Micron-sized silica-walled TS-1 colloidosomes, which were synthesized via an interfacial sol-gel method, can effectively resolve fine TS-1 zeolite separation problems. The interfacial sol-gel process involves construction of a stable W/O Pickering emulsion stabilized by fine TS-1 particles and alkali-catalyzed hydrolysis of silica precursor methyl-trimethoxysilane at the oil-water interface. The successful preparation of TS-1 colloidosome was verified by Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS). The prepared TS-1 colloidosome dimension is tailorable according to water-to-oil volume ratio (Rw/o) and ratio of TS-1 wt to oil volume (Rs/o). On the same time, X-ray diffraction patterns and UV–vis spectra disclosed that the interfacial sol-gel process had no effect on the MFI structure of hierarchical TS-1 particles. The catalytic results showed that the prepared TS-1 colloidosome was a very active and stable catalyst for liquid-phase alkene epoxidation reactions.Micron-sized silica-walled TS-1 colloidosomes were fabricated via an interfacial sol-gel process.Download high-res image (191KB)Download full-size image

•The HDO reaction pathways of guaiacol catalyzed by activated carbon supported molybdenum catalyst were proposed.•Phenolics were selectively converted in the HDO of guaiacol over Mo catalyst.•MoO2/AC and Mo2C/AC were prepared at different reductive temperatures in H2 flow and their catalytic activities were compared.•The effect of solvents on the HDO selectivity of guaiacol was investigated.Activated carbon-supported molybdenum dioxide catalyst and molybdenum carbide catalyst were prepared by reduction in hydrogen with different temperatures. Hydrodeoxygenation (HDO) of guaiacol was investigated in 3 MPa initial H2 pressure with these two catalysts. Phenolics were detected as the main products when catalyzed by molybdenum dioxide catalyst. Through analyzing the HDO selectivity of guaiacol and the intermediates including 1,2-dihydroxy-3-methylbenzene, catechol, phenol and anisole, the HDO reaction pathways of guaiacol over Mo-based catalysts were proposed. In the first stage, transalkylation and breaking of three CO bonds take place to produce 1,2-dihydroxy-3-methylbenzene, catechol, phenol and anisole, whereafter cresol, phenol, toluene and benzene are produced. Furthermore, the effects of reaction temperatures and solvents on HDO of guaiacol were investigated. Using tetralin as solvent, in 3 MPa initial H2 pressure and at 573 K, the conversion of guaiacol reached 98% with phenolics as the major product and the selectivity was greater than 91% after three hours of reaction time.Download full-size image

Phosphorus-doped copper catalysts supported on spherical activated carbon (SAC) were prepared using an incipient wetness impregnation technique. The catalysts were characterized by low-temperature N2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), N2O pulse titration method and thermogravimetric (TG) technologies. The results indicate that the phosphorus-doped Cu-based catalysts exhibit both high activity and good stability. The amount of phosphorus dopant has a significant effect on the catalytic activity of acetylene hydrochlorination and the optimal molar ratio of Cu/P is 2.5. The phosphorus doping facilitates the dispersion of copper species, enhances the interaction between metal and support, and restrains the growth of copper species during acetylene hydrochlorination. These results suggest that this high-activity, good-stability and low-cost catalyst has great potential in industrial applications.

Functional TS-1, partially hydrophobilized with organosilanes, was found to be more active and stable in a Pickering emulsion. In this work, TS-1 behaved simultaneously as a catalyst and solid emulsifier favoring the cyclohexanone ammoximation reaction in organic solvent-free conditions. The composition, structure, formed emulsion morphology, and surface morphology were characterized by Fourier-transform infrared (FT-IR) spectroscopy, conductometer, optical microscope with high speed CCD camera, Brunauer–Emmett–Teller (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It indicated that hydrophobilization provided TS-1 a moderate wettability, allowing the formation of a stable Pickering emulsion, thus promoting the performance in catalyzing the cyclohexanone/H2O2/NH3·H2O reaction in the absence of organic solvents. What is more, due to alkyl groups grafted to TS-1, the zeolites were comparatively exclusive to the aqueous phase and they are more capable of enduring severe environment, i.e., 200 °C, under autogenic pressure.

•Conductivities were monitored to detect the phase inversions.•Infrared (IR) spectrometer was used to investigate the phase inversions.•Mechanism of the inversion of O/W to W/O was analyzed by micrographs.Tween 80 was used as surfactant to create Tween 80-stabilized emulsions, and the consequences of the addition of Span 80 to the emulsions were examined. The conductivities and bottle tests of the emulsion system were monitored in the process to detect the phase inversions. The infrared (IR) spectrometer was used to investigate the phase inversions and the results showed that the adsorption changes of the hydroxyl groups in IR spectra could effectively explain the morphologies changes. Morphological evolution of the emulsion with stirring time was applied to analyze the mechanism of the inversion.

•A reactive dividing-wall column is developed for methyl acetate production.•Both design and control of the reactive dividing-wall column are investigated.•Two control structures are presented and their performances are investigated.•The RDWC can save 7.7% energy, 8.3% operating cost and 15.5% capital investment.•The improved control structure for RDWC can handle disturbances effectively.A reactive dividing-wall column (RDWC) is developed for the production of methyl acetate (MeAc) in this work. Both design and control of the RDWC are investigated by using commercial chemical simulator Aspen Plus and Aspen Dynamics. The optimum RDWC design in terms of total annual costs (TAC) is screened based on the proposed optimization procedure. The results show that about 7.7% savings in energy consumption, 8.3% reduction in operating cost and 15.5% decrease in capital investment can be achieved by the RDWC design compared to the corresponding two-column design. Two control structures (i.e., basic control structure and improved control structure) for the RDWC are presented. The results indicate that the improved control structure can handle disturbances in ±20% feed flow rate and −5 wt% feed composition effectively.

Phosphorus-doped copper catalysts supported on spherical activated carbon (SAC) were prepared using an incipient wetness impregnation technique. The catalysts were characterized by low-temperature N2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), N2O pulse titration method and thermogravimetric (TG) technologies. The results indicate that the phosphorus-doped Cu-based catalysts exhibit both high activity and good stability. The amount of phosphorus dopant has a significant effect on the catalytic activity of acetylene hydrochlorination and the optimal molar ratio of Cu/P is 2.5. The phosphorus doping facilitates the dispersion of copper species, enhances the interaction between metal and support, and restrains the growth of copper species during acetylene hydrochlorination. These results suggest that this high-activity, good-stability and low-cost catalyst has great potential in industrial applications.