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Graphical abstract Highlights • CO 2 -expanded gelation approach was proposed for preparing bimodal porous materials. • CO 2 -expansion induced much short time for gelation. • CTAB template contributed to the surface area and CO 2 -expansion to the pore volume. • Bimodal silica-PW showed good selectivity and short time for 1,8-cineole from α-terpineol. • Bimodal Ni/SiO 2 exhibited excellent performance for phenol hydrogenation to cyclohexanol. Abstract In this work, a facile route was designed to fabricate bimodal porous silica with high surface area and pore volume via a CO 2 -expanded gelation with assistance of CTAB. Parameters such as the amount of CTAB, pressure of CO 2 and agitation time were investigated and optimized. Results showed bimodal silica contained small pore size (around 2 nm) from CTAB templating and large pore size (> 4 nm) from CO 2 -expanded gelation could be easily adjusted by the synthesis conditions. A typical sample with surface area of 1133 m2/g and pore volume of 1.24 mL/g was applied as a catalyst support for phosphotungstic acid, revealing much faster catalysis rate and relatively high selectivity for 1, 8-cineole from α-terpineol than the commercial MCM-41. The approach was also successfully extended to the preparation of bimodal NiO/silica composite, and the reduced Ni/silica showed higher catalysis performance than the unimodal sample for phenol hydrogenation to cyclohexanol. [ABSTRACT FROM AUTHOR]

A solute-saturated supercritical fluid loading (SSFL) process was proposed to load 2-phenylethyl alcohol (PEA) in silica and activated carbon (AC). The adsorption and loading amounts of PEA in carries were investigated at different temperatures (50.0–60.0 °C) and pressures (8.0–14.0 MPa) by a column sampling method. By using a high-pressure quartz spring method, the adsorption amounts of the binary PEA and CO 2 in silica were determined. The retention of PEA in the SSFL powder flavors was evaluated by a nitrogen-purging method. Results revealed that, compared with AC, silica had high loading of PEA (maximum 0.484 g/g) and showed better results in PEA preservation from loss at room temperature and control release at higher temperature; PEA suppressed the adsorption of CO 2 at relatively high pressure. Discussion indicated that precipitation and adsorption contributed to the high loading of PEA in silica, while adsorption mainly contributed to that in AC. [ABSTRACT FROM AUTHOR]

Abstract: A supercritical fluid-based method is proposed to produce coenzyme Q10 (CoQ10) nanoparticles. First, CoQ10/polyethylene glycol 6000 composite particles are prepared by a modified PGSS (particles from gas-saturated solutions) process with controlling the flow rate of the gas-saturated solution. Then, CoQ10 nanoparticles are obtained by dissolving the composite particles into water. The effect of experimental variables of the modified PGSS process, including pressure, temperature, flow rate of the gas-saturated solution, and mass fraction of CoQ10, on the CoQ10 particle size and particle size distribution was investigated. Results show that CoQ10 slurry product with a median diameter of 190nm and yield of 89.8% can be prepared at an optimum condition (operating pressure of 25MPa, operating temperature of 80°C, gas-saturated solution flow rate of 1.02mL/min, CoQ10 mass fraction of 40% and nozzle diameter of 100μm) via the supercritical fluid-based method. [Copyright &y& Elsevier]