A novel method was proposed for the in situ synthesis of magnetite-containing mesoporous silica SBA- 16 via a sol-gel process coupled with precipitation and oxidation. The effect of the added amounts of reactants on the mesostructural and magnetic properties of the magnetic mesoporous silica was investigated. It was determined that the synthesized magnetic mesoporous silica with a total pore volume of 0.64-0.96 cm 3 /g and an average pore diameter of 4.0-14.9 nm had a relatively high saturation magnetization value (1.11-5.77 emu/g) and a large surface area (258-747 m 2 /g). Lysozyme was chosen as a model protein to test the performance of the magnetic mesoporous silica as a protein adsorbent. The high adsorption capacity (up to 212 mg/g) suggested a promising future as bimolecular hosts for the magnetic mesoporous silica.
To get high purity caprolactam is a challenging task in the chemical fiber industry. To date, reports on the prediction of the distribution of caprolactam and its derivative chemicals have been few. In this study, the ex-traction of caprolactam with toluene as the extractant and N-methyl caprolactam with benzene and toluene as the extractants has been carried out. By defining new UNIFAC groups and calibrating related interaction parameters, a UNIFAC method was introduced to predict the equilibrium concentration of caprolactam and methyl caprolactam in toluene or benzene extraction processes. The calculated results fit very well with the experimental data. Using the UNIFAC model, the selectivity of extractants can be predicted.
This paper presents the experimental results of liquid-liquid microflows in a coaxial microfluidic device with mass transfer.Three working systems were n-butanol + phosphoric acid(PA) + water,methyl isobutyl ketone(MIBK) + PA + water,30% kerosene in tri-n-butylphosphate(TBP) + PA + water.The direction and intensity of mass transfer were adjusted by adding PA in one of two phases mutual saturated in advance.When PA transferred from the organic phase to the aqueous phase,tiny aqueous droplets may generate inside the organic phase by mass transfer inducement to form a new W/O/W flow pattern directly on some special cases.Once the PA concentration was very high,violent Marangoni effect could be observed to throw part of organic phase out of droplets as tail.The interphase transfer of PA could expand the jetting flow region,in particular for systems with low or medium inter-facial tension and when the mass transfer direction was from the aqueous phase to the organic phase.
This paper presents the integrated results of a series of new methods for preparing mesoporous silica spheres as high-performance liquid chromatography(HPLC)packing materials.The separation performance of the mesoporous spheres materials has also been determined.Micrometer-sized silica spheres with uniform spherical morphologies and ordered mesostructures were first successfully synthesized by the method employing a water-soluble polymer-assisted assembly.Then the templates for getting ordered mesoporous materials with high-density silanol groups were removed by using hydrothermal oxidation.Finally the silica spheres were functionalized with C8 alkyl groups by surface modification under hydrothermal conditions.The resultant functionalized silica spheres were demonstrated to be excellent packing materials for HPLC.
