In this article, the phase equilibrium measurement based on the synthetic method under high pressure using reflected light is presented. The vapor phase separation point was determined by measuring the displacement of the piston with a laser displacement meter using the rapid volume change caused by the vapor phase generation. The liquid phase separation point was determined by measuring the reflected light intensity with a light sensor using the light scattering caused by the liquid phase generation. This method was successful in reducing human error.
Supercritical extraction can be applied for separation and purification of bioactive compounds in pharmaceutical and cosmetic fields. Recently, microfluidic system has been utilized for the supercritical extraction because of controllable mass and heat transfer. The flow patterns in the microfluidic system for supercritical CO2 + solvent mixture are also studied at various operation factors, such as temperature, pressure, flow rate and solvent species. This article gives the extraction of phenolic acids into supercritical CO2 from the aqueous solution using microfluid system. The effect of the flow patterns in the microfluid system on the extraction efficiency is also discussed.
In this article, spinel structure MFe2O4 (M = Ni, Cu, Zn) nanoparticles from Fe(NO3)3 and M(NO3)2 (M = Ni, Cu, Zn) aqueous solutions could be synthesized continuously with a flow reactor at 673 K, 30 MPa, and 0.35 - 2.00 s residence time. The particles were characterized by TEM, XRD, and XRF to obtain sizes, crystal structures, lattice parameters, and molar ratios, respectively. Solid solution nanoparticles of MFe2O4 with a cubic spinel structure and an average particle size under 20 nm were obtained. M/Fe molar ratio of the obtained particles evaluated by XRF analyses was lower than the ratio in the stating solution. This result suggests the formation of nonstoichiometric MFe2O4 particles. Further, minimal M/Fe molar ratio of the particle to maintain stable phase at 673 K was investigated by calcination at 673 K for 3 h and it was found to be about 0.35 for Zn/Fe.
In this article we will discuss our current research conducted for liposome production in high pressure CO2-water systems using direct ultra-sonication. Based on our results, we will discuss the advantages of high pressure systems and propose a reaction mechanism focusing on the micro-phase separation of CO2 and water.
In this article, a specific system for both hydrogen formation and hydrogenation of compounds with hydrogen permeable membrane electrode by electrolysis of water is introduced. Hydrogen permeable palladium membrane played an important role as a cathode for electrolysis of water and hydrogen purifier by the permeation of hydrogen produced. The high pressure at electrolysis side improved a amount of hydrogen permeated through the membrane. The hydrogenation of organics proceeded in Pd surface and catalysts near the membrane. This system is compact and useful for production of hydrogen and chemical hydride in a narrow space.