摘要:
A catalyst for catalytically reducing nitrogen oxides present in an exhaust gas in the presence of a reducing gas to convert said nitrogen oxides to harmless substances, which comprises a mixture consisting essentially of the oxides of V and Nb.
摘要:
The present invention relates to a process for separating 2,7-DMN, characterized in that a mixture containing at least 50% by weight of 2,7-DMN and the other DMN isomers obtained by preliminarily concentrating a fraction in the range of 250.degree.-270.degree. C. of catalytically cracked petroleum oil is preliminarily adjusted to a temperature of 60.degree.-90.degree. C. to form a slurry containing the crystal of 2,7-DMN, which is placed in a tightly sealed pressure vessel, adiabatically pressurized to the range of 500-2,500 kgf/cm.sup.2 and solidified to form a state of co-existing of solid and liquid phases, liquid is then discharged under pressure from the solid-liquid co-existing system, the solid remaining in the vessel is pressed to discharge the liquid remaining between the solid particles, which are integrated to give 2,7-DMN having a purity of 98% by weight or more.
摘要:
A method for the liquefaction of brown coal which comprises effecting primary hydrogenation at a temperature and pressure sufficient to promote the efficient hydrogenation of a slurry prepared by adding an iron-based catalyst and a slurrying solvent to brown coal; distilling all or a portion of the primary hydrogenation product, whereby a naphtha fraction, a middle distillate oil fraction, a heavy distillate oil fraction and a distillation residue are produced; recycling a portion of said middle distillate oil, said heavy distillate oil fraction and said distillation residue to said primary hydrogenation step as the slurrying solvent; removing ash from the remaining portion of the distillation residue, thereby separating the same into an insoluble fraction containing ash, insoluble organic matter or a mixture thereof, and a soluble fraction as a solution in said solvent; and feeding said soluble fraction and said middle and heavy distillate fractions, to a fixed-bed column reactor packed with a molybdenum-based catalyst for secondary hydrogenation at a temperature and pressure sufficient to promote the efficient hydrogenation thereof; and separating the naphtha fraction from the secondary hydrogenation product and recycling all or a portion of the remainder to said primary hydrogenation step as the slurrying solvent therefor.
摘要:
A luer needle unit and an injector effectively prevent a user's fingers from being hurt when a disposable needle is separated from the luer needle after use, while realizing simple and positive attachment of the luer needle to a supporting cap. Guide protrusions and guide recesses are provided between the luer needle and the supporting cap to prevent the rotation thereof. Guiding projecting portions are formed in the supporting cap to guide a needle part of the luer needle in the axial direction.
摘要:
Described herein is a process for separating solid indole in refined form with an extremely high degree of purity from a mixture containing more than 50 wt % of indole, in which a pressure of 700-2500 atms is applied to the mixture in a high pressure vessel, and solid-liquid separation is effected continuedly under pressurized state with an initial temperature in the range of 50.degree.-65.degree. C.