摘要:
The invention relates to a process for preparing an alcoholic solution of an alkali metal alkoxide from alkali metal hydroxide and alcohol in a reaction column, the alcohol and the alkali metal hydroxide being conducted in countercurrent, which is characterized in that a reflux ratio of at least is established in the reaction column.
摘要:
Alkali metal salt of formula (I): MOYXR1 (I), and its solution can be prepared in high yields, particularly high space-time yields, and with high purities by reacting an alcohol of the formula (Ia): HOYXR1 (Ia), in a solvent mixture with an alkali metal salt of formula (II): MOR2 (II), or by reacting the alcohol (Ia) in a solvent mixture with an alkali metal hydroxide. Part of the liberated alcohol of formula (IIa): HOR2 (IIa) or a part of the liberated water is distilled from the solvent mixture, initially, without addition of an entrainer. Subsequently, a remainder of the liberated alcohol of formula (IIa) or the liberated water is distilled from the solvent mixture with the aid of at least one organic solvent as entrainer. In formula (I) and in formula (II), M is Li, Na, K, Rb or Cs. In formula (I) and in formula (Ia): Y is (C1-C8)-alkylene, X is O, S or NR1, and R1 is H, (C1-C8)-alkyl, (C2-C8)-alkenyl, (C2-C8)-alkynyl, (C3-C8)-cycloalkyl, (C6-C18)-aryl, (C7-C19)-aralkyl, (C3-C18)-heteroaryl, (C4-C19)-heteroaralkyl, ((C1-C8)-alkyl)1-3-(C3-C8)-cycloalkyl, ((C1-C8)-alkyl)1-3-(C6-C18)-aryl or ((C1-C8)-alkyl)1-3-(C3-C18)-heteoraryl. In formula (II) and in formula (IIa), R2 is methyl, ethyl, propyl, isopropyl, sec-butyl, isobutyl or tert-butyl.
摘要:
An unsaturated, cyclic orthoester is prepared by reacting an unsaturated carboxylic acid with glycidol, thereby obtaining a reaction mixture; and adding an orthoester to the reaction mixture, thereby obtaining said unsaturated, cyclic orthoester.
摘要:
The invention relates to a process for preparing an alcoholic solution of an alkali metal alkoxide from alkali metal hydroxide and alcohol in a reaction column, the alcohol and the alkali metal hydroxide being conducted in countercurrent, which is characterized in that a reflux ratio of at least 0.05 is established in the reaction column.
摘要:
Provided is a composition comprising an alkali metal glycerate or an alkaline earth metal glycerate and glycerol, and a method for preparing the same. Also provided are methods for removing a fatty acid from a fatty acid-comprising glyceride or a fatty acid alkyl ester (deacidifying) or drying a glyceride or fatty acid alkyl ester, involving contacting a mixture of the fatty acid and the fatty acid-comprising glyceride or the fatty acid alkyl ester, or mixing the glyceride or fatty acid alkyl ester, with the composition.
摘要:
A method to transesterify triglycerides in the presence of a catalyst system comprising a transesterification catalyst selected from the group of the alkali metal and alkaline earth metal alkoxides and the alkali metal hydroxides, and at least one activator other than the transesterification catalyst, selected from the group comprising salt compounds, titanates and non-salt compounds having a density of at least 0.9 g/ml, is provided. Additionally provided is a method to prepare biodiesel by transesterification of a natural fat.
摘要:
An unsaturated, cyclic orthoester is prepared by reacting an unsaturated carboxylic acid with glycidol, thereby obtaining a reaction mixture; and adding an orthoester to the reaction mixture, thereby obtaining said unsaturated, cyclic orthoester.
摘要:
2-Chloro-1,1,1-trialkoxyethane of formula (II): wherein R1 to R3, which may be the same or different, are alkyl, or any two of the alkyl groups taken together form a cyclic group, is prepared by reacting 1,1,1-trialkoxyethane with gaseous or liquid chlorine in the presence of alcohol solvent in an amount ranging from 0.1% to 20 wt %, based on the amount of 1,1,1-trialkoxyethane reactant.
摘要:
The invention relates to a catalyst system composed of metallocenes comprising substituents containing fluorine, a method for producing said system and its use for the polymerization of olefins.
摘要:
The present invention relates to a transition metal compound of the formula I L.sub.n (X.sub.m A.sub.t R.sup.1.sub.q).sub.s MY.sub.r (I), where M is a metal atom of group IIIb, IVb, Vb or VIb of the Periodic Table of the Elements, L are identical or different and are each a .pi.-ligand or an electron donor, n is 1, 2, 3 or 4, Y are identical or different and are each a hydrogen atom, a halogen atom or an 1-dentate C.sub.1 -C.sub.40 -group, where l is 1, 2, 3 or 4, r is 0, 1, 2, 3, 4 or 5, and at least one of the radicals L bears at least one group X.sub.m A.sub.t R.sup.1.sub.q, where X are identical or different and are each a hetero atom or a C.sub.1 -C.sub.40 -group, m is 0 or 1, A is an atom of group IIIa, Va or VIa of the Periodic Table of the Elements, t is 1, R.sup.1 are identical or different and are each a C.sub.1 -C.sub.40 -group, q is 1, 2, 3, 4 or 5 and s is an integer from 1 to 20. The transition metal compound of the invention is suitable as a catalyst component for olefin polymerization.