摘要:
The present invention relates to a process for preparing post-crosslinked polymer bead with increased surface area and pore volume, and suitable pore size, allowing the separation of organic compounds by post-crosslinking gel-type copolymer bead whose crosslinking degree is low and initial surface area is small, or macroporous-type copolymer bead whose crosslinking degree is high and initial surface area is intermediate in the presence of a Friedel-Crafts catalyst, and polymer beads produced thereby. Though the surface area and pore volume of polymer beads may be varied depending on physical properties of copolymer beads and Friedel-Crafts reaction conditions, the present invention provides polymer beads with larger surface area than that of commercially available polymeric adsorbents produced by the conventional method employing a porogen only. Further, the polymer beads may be used as polymeric adsorbent and catalyst carrier, since they exhibit a high adsorption capacity for organic compounds in an aqueous solution, and chemically modified ones may be employed as polymer carrier, ion-exchange resin, and chelate resin.
摘要:
The present invention relates to a heterogeneous polyimide-supported transition metal complex catalyst for epoxidation of olefin, which is prepared by impregnating a heat- and acid-resistant polyimide resin with a homogeneous metal catalyst of molybdenum, vanadium, tungsten or titanium, and a process for preparing epoxy compounds using the same. The heterogeneous polyimide-supported transition metal complex catalyst of the invention provides superior catalytic activity, selectivity and stability in the epoxidation of higher olefin. Further, the catalyst of the invention has strong resistance against heat and acid. Besides, the catalyst of the invention may provide the following advantages which are critical in industrial use: it permits relatively high yield of epoxy compounds; and, it can be easily separated from the reaction product, which eases recycling of the catalyst.
摘要:
New types of photocatalyst materials are disclosed together with methods for preparing and using these materials, as well as air treatment systems incorporating such materials. The photocatalyst materials of this invention consist essentially of very small particles of a first-metal oxide, the first-metal being a metal that exhibits photo-induced semiconductor properties, having ions of a second-metal dispersed throughout its lattice structure, the second-metal being selected from the group of dopant metals. Such photocatalyst materials are prepared by the steps of mixing first-metal and second-metal precursors, removing nonessential ions from the mixture, drying the resulting product, and calcinating the dried product to produce the completed photocatalyst material.
摘要:
New types of photocatalyst materials are disclosed together with methods for preparing and using these materials, as well as air treatment systems incorporating such materials. The photocatalyst materials of this invention consist essentially of very small particles of a first-metal oxide, the first-metal being a metal that exhibits photo-induced semiconductor properties, having ions of a second-metal dispersed throughout its lattice structure, the second-metal being selected from the group of dopant metals. Such photocatalyst materials are prepared by the steps of mixing first-metal and second-metal precursors, removing nonessential ions from the mixture, drying the resulting product, and calcinating the dried product to produce the completed photocatalyst material.