摘要:
A process for the selective alkylation of monoalkylbenzene into dialkylbenzenes wherein the para isomer of the disubstituted product is present in a concentration greater than in a thermodynamic equilibrium is provided. The method comprises passing the monoalkylbenzene and an alkylating agent capable of methylation. ethylation or propylation through a reaction zone containing an unmodified crystalline silica catalyst of the silicalite type having the monoclinic symmetry.
摘要:
There are provided crystallized borosilicate glass zeolite catalysts which are para-selective in the alkylation of benzene and derivatives thereof and beta-selective in the alkylation of naphthalene and derivatives thereof. There is provided a process for the production of such catalysts wherein a borosilicate type glass is reacted with a zeolite synthesis template. There is also provided a selective alkylation process for the alkylation of benzene and its derivatives and of naphthalene and its derivatives wherein these are reacted with an alkylation agent in the presence of such catalyst.
摘要:
A synthetic porous crystalline zeolite having a distinctive X-ray diffraction pattern and designated as ZSM-58 has a composition in the as-synthesized form, on an anhydrous basis and in terms of moles of oxides per 100 moles of silica, expressed by the formula: wherein M is an alkali or alkaline earth metal, n is the valence of M, and R is the methyltropinium cation of the formula (I). ZSM-58 is useful as a catalyst for aromatic and oxygenate conversion process. I
摘要:
An aromatic hydrocarbon in which at least one hydrogen atom on the ring is substituted by a group selected from the class consisting of unsubstituted or lower alkyl-substituted tricyclo [5.2.1.0 1,6 ]dec-3-yl, tricyclo [5.2.1.0 2,6 ]dec-4-yl, tetracyclo [6.2.1.1 3,6 .0 2.7 ]dodec-4-yl and tetracyclo [6.2.1.1 3,6 .0 2,7 ]dodec-5-yl groups, or its hydrogenation product. The compound is prepared by reacting an aromatic hydrocarbon having at least one hydrogen atom on the ring with a compound selected from the group consisting of unsubstituted or lower alkyl-substituted tricyclo-[5.2.1.0 2,6 ]dec-3-ene and tetracyclo [6.2.1.1 3,6 .0 2,7 ]-dodec-4-ene in the presence of a Friedel-Crafts catalyst, or hydrogenating the thus- obtained compound in the presence of a hydrogenation catalyst. The compound is useful as an additive for adhesives.
摘要:
A method for promoting the activity and/or extending the life of a cation-exchangeable layered clay catalyst in reactions susceptible to catalysis by protons which method comprises the addition to the catalyst of water as the sole additive. The quantity of water employed is suitably up to 40°C. preferably up to 10% based on weight of reactants. The layered clay catalyst can be for example montmorillonite, bentonite or vermiculite. Suitable proton catalysed reactions include formation of esters, (eg by reaction of olefin and carboxylic acid), ethers, aldehydes, thioethers and alkylation and cracking reactions.
摘要:
A solvent for the dye of pressure-sensitive recording paper which solvent has no offensive odor and both the color developing rate and the density of developed color are excellent. The solvent is is characterized in that it comprises a fraction having boiling points in the range of 270 to 350°C which is prepared by distilling the heavier products obtained from the process for producing ethyltoluene by alkylating toluene with ethylene in the presence of synthetic zeolite catalyst.
摘要:
A method is provided for removing trace amounts of organic chlorides from feedstocks by contacting the feedstock with a guard bed catalyst comprising shaped particles formed by extruding a mixture of magnesium oxide and a binder inert to the feedstock. The process has particular importance in removing organic chlorides from toluene feedstocks prior to contacting toluene with a disporportionation or alkylation catalyst comprising magnesium-ZSM-5.
摘要:
Method for the synthesis of ZSM-5 zeolites at atmospheric pressure, at a temperature preferably from 60 to 100°C wherein: a) an aqueous solution containing a quaternary ammonium compound (OA) is added to a second aqueous solution, containing a Si compound, a Na compound and a potassium halogenide (K Hal.), according to the molar ratios: -Na 2 O/SiO 2 ≥0.20 (preferably from 0.25 to 2); -H 2 O/SiO 2 = = from 5 to 100 (preferably from 10 to 50); -K Hal/SiO 2 = from 0.03 to 0.50; b) a third aqueous solution, containing A1 sulphate, is added to the mixture obtained according to a); c) to the mixture obtained according to b) an aqueous solution of H 2 SO 4 is added; wherein the molar ratio Y = (QA/SiO 2 ) is from 0.02 to 0.08 and the molar ratio Z = SiO 2 /Al 2 O 3 is from 25 to 210, said Y ratio and the molar ratio X = OH - /SiO 2 being represented by points lying within triangles limited by the following 3 straight lines: A) Y = 0.7 X; B) X = K/Z, wherein K = 4 (K being constant); C) Y = - 2/3 X + 1 - H, wherein the constant H is obtained from the expression: H = 1/2 (45/Z) 0,317 .
摘要:
The present invention relates to a method for preparing a zeolite composition comprising a crystalline zeolite having deposited thereon a coating of silica which extensively covers and resides substantially exclusively on the external surface thereof, and to the composition so prepared. The present invention also relates to a process for the selective conversion of aromatic hydrocarbon feedstocks to a product rich in para-dialkyl substituted benzenes over a catalyst composition comprising such a silica-modified zeolite composition.