Abstract: The present invention is related to a method for preparing lactam represented by the following formula:
wherein R is C2-10 alkylene which may be optionally substituted with C1-6 alkyl or phenyl; R′ is a hydrogen atom, C1-6 alkyl, C1-6 hydroxyalkyl or phenyl. The method for preparing lactam comprises an amination reaction using crystalline aluminosilicate zeolites as catalysts under the condition of gas phase in the presence of (a) lactone, (b) amine and/or ammonia and (c) water.
Abstract: The present invention relates to a catalyst for preparing a lactone, which is prepared by supporting a cupric compound, a zinc compound and at least one alkaline earth metal compound on the supporter. The present invention also relates to a method for preparing a lactone, which comprises a dehydrocyclization reaction of a diol under a gas phase in the presence of the aforementioned catalyst after activating said catalyst. The catalyst for preparing lactone of the present invention is quite economic because of its high activity, long lifetime and high selectivity of products.
Abstract: The present invention is related to a method for preparing polyether polyol or copolymerized polyether polyol, which uses an acid catalyst consisting of heteropoly acidic salts and oxides and/or binders. It allows tetrahydrofuran and/or cyclic ether compounds to carry out the ring-opening polymerization or ring-opening copolymerization with/without telogen, and obtains polyether polyol or copolymerized polyether polyol. An acid catalyst is used in the present invention because of its low solubility in organic solvent, so its process is simpler and the catalyst is easy to recycle for repeated use. As well, its preparation process is highly advantageous.
Type:
Grant
Filed:
November 23, 1999
Date of Patent:
November 6, 2001
Assignee:
Dairen Chemical Corporation
Inventors:
Shien Chang Chen, Fu Shen Lin, June Yen Chou, Liang An Hsu, Ming Hui Chu, Chine Chung Huang, Ming Hsiung Shao
Abstract: The present invention relates to a catalyst for preparing a lactone, which is prepared by supporting a cupric compound, a zinc compound and at least one alkaline earth metal compound on the supporter. The present invention also relates to a method for preparing a lactone, which comprises a dehydrocyclization reaction of a diol under a gas phase in the presence of the aforementioned catalyst after activating said catalyst. The catalyst for preparing lactone of the present invention is quite economic because of its high activity, long lifetime and high selectivity of products.
Abstract: This invention relates to a process for producing polyester fibers with enhanced dyeability, lesser elongation and greater strength, which comprises combining 2-methyl-1,3-propanediol into a mixture containing terephthalic acid, or an alkyl ester thereof, and a (C.sub.2-6)alkanediol, and carrying out polymerization. The resultant polyester copolymer is then spun to produce polyester fibers. This invention also relates to the polyester fibers produced by this process. These polyester fibers exhibit enhanced dyeability, lesser elongation and greater strength than un-improved polyester fibers.
Type:
Grant
Filed:
September 11, 1998
Date of Patent:
June 29, 1999
Assignee:
Dairen Chemical Corporation
Inventors:
Shien Chang Chen, Fu Shen Lin, June-Yen Chou, Hsing Yun Wang, Mao Song Lee, Mei-Sui Chen, Yann Jyh Huang, Hung Shu Sun
Abstract: This invention is directed to a process for producing cyclic ethers by liquid phase reaction, which comprises using a crystalline aluminosilicate zeolite as the catalyst, and subjecting an alkanediol to cyclodehydration at a temperature less than the boiling point of the alkanediol to obtain the corresponding cyclic ether.
Type:
Grant
Filed:
April 28, 1998
Date of Patent:
June 29, 1999
Assignee:
Dairen Chemical Corporation
Inventors:
Shien Chang Chen, Cheng Chang Chu, Fu Shen Lin, June Yen Chou, Ming Hui Chu
Abstract: The present invention relates to a modified Raney nickel catalyst which can serves as hydrogenation catalyst for hydroxy aldehydes, such as 4-hydroxy-butanal, and 2-methyl-3-hydroxypropanal and hydroxy cyclic ethers such as 2-hydroxy-tetrahydrofuran. Further, a process for preparing diols by using the modified Raney nickel catalyst is provided.
Type:
Grant
Filed:
April 15, 1996
Date of Patent:
March 30, 1999
Assignee:
Dairen Chemical Corporation
Inventors:
Shien Chang Chen, C. C. Chu, F. S. Lin, J. Y. Chou, C. C. Huang
Abstract: A process for the preparation of tertiary olefins by decomposition of a tertiary alkyl ether in the vapor phase in the presence of a catalyst, wherein the catalyst used is a composition of: (i) 5 to 95 percent by weight of a crystalline aluminosilicate zeolite having a silica-to-alumina mole ratio of at least about 5 and a Constraint Index of about 1 to about 12, and (ii) 95 to 5 percent by weight of a binder selected from amorphous silica, alumina, silica-alumina and mixtures thereof.
Type:
Grant
Filed:
December 9, 1991
Date of Patent:
July 13, 1993
Assignee:
Dairen Chemical Corporation
Inventors:
S. C. Chen, C. C. Chu, F. S. Lin, Liang Sheu, Shing Y. Wang
Abstract: A process for the preparation of methyl formate by the vapor phase dehydrogenation of methanol in the presence of a catalyst composed of copper oxide, a chromium oxide and a sodium compound is described.
Abstract: A process is disclosed for the preparation of high purity carbon monoxide by heating methyl formate in the presence of a catalyst of a precious metal compound with or without a promoter of alkali or alkaline earth metal compound.
Abstract: An improved method of catalytic gaseous chemical synthesis of pyridine by reaction of ammonia and a carbonyl compound, preferably with added hydrogen, is described herein. The process employs as the catalyst a crystalline aluminosilicate zeolite which has been ion exchanged with a Group VIII metal of the Periodic Table. The preferred metal is palladium. Suitably, the Group VIII metal is present in an amount of about 0.01% to 5% by weight of the catalyst, preferably 0.1% to 2%. The crystalline aluminosilicate zeolite catalyst suitably has a silica to alumina mole rate of at least 15, preferably 30 to 200, and optimally, about 120 to 150. The process of the invention provides a high and selective yield of pyridine over a prolonged reaction period, and affords facile restorability of the catalyst.
Type:
Grant
Filed:
June 6, 1988
Date of Patent:
September 12, 1989
Assignee:
Dairen Chemical Corporation
Inventors:
Wan J. Cheng, Fu S. Lin, Yuh L. Jong, Fu J. Huang