Patent classifications
B01J37/26
Aromatization catalyst activity and selectivity improvement with alcohol addition during catalyst preparation
Methods for producing supported catalysts containing a transition metal and a bound zeolite base are disclosed. These methods employ a step of impregnating the bound zeolite base with a transition metal precursor in a solvent composition containing water and from about 5 wt. % to about 50 wt. % of a C.sub.1 to C.sub.3 alcohol compound, a chlorine precursor, and a fluorine precursor. The resultant supported catalysts have improved catalyst activity and selectivity, as well as lower fouling rates in aromatization reactions.
Chromium-free catalyst for gas-phase fluorination and application thereof
Disclosed in the present invention is a chromium-free catalyst for gas-phase fluorination and an application thereof. The precursor of the related chromium-free catalyst for gas-phase fluorination consists of a compound containing iron element, a compound containing rare earth metal element and a compound containing element A, wherein element A is one selected from Ca, Al, Mg and Ti, the precursor is subjected to calcination and fluorination treatment to obtain the chromium-free catalyst for gas-phase fluorination. The precursor of the catalyst is calcined at 400-500° C. and fluorinated with hydrogen fluoride at 350-450° C. to obtain the chromium-free fluorinated catalyst. The catalyst has characteristics of being chromium-free and environment-friendly, good catalytic activity and long life etc. The catalyst can be used for preparing hydrofluoroolefins or hydrochlorofluoroolefins from halohydrocarbons.
Chromium-free catalyst for gas-phase fluorination and application thereof
Disclosed in the present invention is a chromium-free catalyst for gas-phase fluorination and an application thereof. The precursor of the related chromium-free catalyst for gas-phase fluorination consists of a compound containing iron element, a compound containing rare earth metal element and a compound containing element A, wherein element A is one selected from Ca, Al, Mg and Ti, the precursor is subjected to calcination and fluorination treatment to obtain the chromium-free catalyst for gas-phase fluorination. The precursor of the catalyst is calcined at 400-500° C. and fluorinated with hydrogen fluoride at 350-450° C. to obtain the chromium-free fluorinated catalyst. The catalyst has characteristics of being chromium-free and environment-friendly, good catalytic activity and long life etc. The catalyst can be used for preparing hydrofluoroolefins or hydrochlorofluoroolefins from halohydrocarbons.
Particle Size Control of Metallocene Catalyst Systems in Loop Slurry Polymerization Reactors
Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.
PROCESS FOR THE PREPARATION OF 1,3,3,3-TETRAFLUOROPROPENE
Disclosed is a process for the preparation of 1,3,3,3-tetrafluoropropene, comprising: (a) a compound having the formula CF.sub.3-xCl.sub.xCHClCHF.sub.2-yCl.sub.y and in the presence of a compound catalyst, undergoes, through n serially-connected reactors, gas-phase fluorination with hydrogen fluoride, producing 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane; in said formula, x=1, 2 or 3; y=1 or 2, and 3≦x+y≦5; (b) 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane undergo, in the presence of a dehalogenation catalyst, gas-phase dehalogenation with hydrogen, producing 3-chloro-1,3,3-trifluoropropene, and 1,1,3,3-tetrafluoropropene; (c) 3-chloro-1,3,3-trifluoropropene and 1,1,3,3-tetrafluoropropene undergo, in the presence of a fluorination catalyst, gas-phase fluorination with hydrogen fluoride, producing 1,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 1,3,3,3-tetrafluoropropene.
PROCESS FOR THE PREPARATION OF 2, 3, 3, 3-TETRAFLUOROPROPENE
Disclosed is a process for the preparation of 2,3,3,3-tetrafluoropropene, comprising the following two reaction steps: a. a compound having the formula CF.sub.3-xCl.sub.xCF.sub.2-yCl.sub.yCH.sub.2Cl undergoes gas-phase fluorination with hydrogen fluoride through n serially-connected reaction vessels in the presence of a compound catalyst producing 2,3-dichloro-1,1,1,2-tetrafluoropropane, 1,2,3-trichloro-1,1,2-trifluoropropane, and 1,3-dichloro-1,1,2,2-tetrafluoropropane; in said formula, x=1, 2, 3, y=1, 2, and 3≦x+y≦5; b. the 2,3-dichloro-1,1,1,2-tetrafluoropropane, 1,2,3-trichloro-1,1,2-trifluoropropane, and 1,3-dichloro-1,1,2,2-tetrafluoropropane undergo gas-phase dehalogenation with hydrogen in the presence of a dehalogenation catalyst, producing 2,3,3,3-tetrafluoropropene and 3-chloro-2,3,3-trifluoropropene, then separation and refining are performed, producing 2,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 2,3,3,3-tetrafluoropropene.
Methods of preparing an aromatization catalyst
Catalysts and method of preparing the catalysts are disclosed. One of the catalysts includes a zeolite support, a Group VIII metal on the zeolite support, and at least two halides bound to the zeolite support, to the Group VIII metal, or to both, and can have an average crush strength greater than 11.25 lb based on at least two samples of pellets of the catalyst measured in accordance with ASTM D4179.
Methods of preparing an aromatization catalyst
Catalysts and method of preparing the catalysts are disclosed. One of the catalysts includes a zeolite support, a Group VIII metal on the zeolite support, and at least two halides bound to the zeolite support, to the Group VIII metal, or to both, and can have an average crush strength greater than 11.25 lb based on at least two samples of pellets of the catalyst measured in accordance with ASTM D4179.
Particle size control of metallocene catalyst systems in loop slurry polymerization reactors
Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.
FLUORINATED CATALYST SUPPORTS AND CATALYST SYSTEMS
Catalyst systems and methods for making and using the same. A method for making a catalyst support includes forming a mixture of a support material and a fluoride donor. The mixture is added to a fluidized bed reactor. The mixture is fluidized to form a fluidized bed while maintaining a ratio of a pressure drop across a distributor plate to a pressure drop across the fluidized bed of greater than about 7%. The mixture is calcined to decompose the fluoride donor, forming a fluorinated support.