The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 2001
Filed:
Jun. 28, 2000
Sumitomo Chemical Company, Limited, Osaka, JP;
Abstract
A process for producing a pentacyl-type crystalline zeolite is provided which comprises the steps of (i) preparing a mixture of a silicon compound, water and tetrapropyl ammonium hydroxide, (ii) conducting a hydrothermal reaction of the mixture to obtain a reaction mixture containing zeolite crystals, (iii) separating zeolite crystals from the reaction mixture to collect a remaining solution, (iv) calcinating the resulting zeolite crystals, (v) treating the calcinated zeolite crystals with a solution such as ammonia water and (vi) recycling the solution collected in step (iii) to step (i), wherein in the mixture prepared in step (i) a molar ratio of hydroxide ion to silicon is from about 0.1 to about 0.4 and a molar ratio of potassium to silicon is about 0.1 or less. With this process, a zeolite catalyst having good performance can be produced with good reproducibility.