摘要:
2-Cyclododecyl-propanol [sic], which is in demand as musk scent, is prepared in an advantageous industrial process by reacting cyclododecene with an excess of propionic acid or of a propionic acid derivative in the presence of catalytic amounts of a free-radical initiator, and subsequently catalytically hydrogenating the 2-cyclododecylpropionic acid which is formed or the corresponding 2-cyclododecylpropionic acid derivatives.
摘要:
A process for hydrogenating a benzenepolycarboxylic acid or a derivative thereof or a mixture of two or more thereof by bringing the benzenepolycarboxylic acid or the derivative thereof or the mixture of two or more thereof into contact with a hydrogen-containing gas is carried out in the presence of a catalyst which comprises as active metal at least one metal of transition group VIII of the Periodic Table alone or together with at least one metal of transition group I or VII of the periodic table applied to a support which contains macropores with the proviso that if dimethyl terephthalate is hydrogenated, the hydrogenation using a catalyst which comprises as active metal ruthenium either alone or together with at least one metal of transition group I, VII or VIII of the Periodic Table applied to a support, where the support has a mean pore diameter of at least 50 nm and a BET surface area of at most 30 m2/g and the amount of the active metal is from 0.01 to 30% by weight, based on the total weight of the catalyst, and the ratio of the surface areas of the active metal and the catalyst support is less than 0.05, and/or a catalyst which comprises as active metal ruthenium either alone or together with at least one metal of transition group I, VII or VIII of the Periodic Table in an amount of from 0.01 to 30% by weight, based on the total weight of the catalyst, applied to a support, where from 10 to 50% of the pore volume of the support is formed by macropores having a pore diameter in the range from 50 nm to 10,000 nm and from 50 to 90% of the pore volume of the support is formed by mesopores having a pore diameter in the range from 2 to 50 nm, where the sum of the pore volumes adds up to 100%, is excluded, and novel hydrogenation products, obtainable by hydrogenating benzenepolycarboxylic acid (derivatives) as well as their use as plasticizers in plastics.
摘要:
A process for preparing 1,4-butanediol by continuous catalytic hydrogenation of 1,4-butynediol comprises reacting 1,4-butynediol with hydrogen in the liquid continuous phase in the presence of a heterogeneous hydrogenation catalyst at from 20 to 300° C., a pressure of from 1 to 200 bar and values of the liquid-side volumetric mass transfer coefficient kLa of from 0.1 s−1 to 1 s−1 a) using a catalyst suspended in the reaction medium, where if a packed bubble column is employed this is operated in the upflow mode and at a ratio of gas leaving the reaction vessel to gas fed to the reaction vessel of from 0.99:1 to 0.4:1, or b) passing the liquid and gas in cocurrent in an upward direction through a fixed-bed reactor operated in the gas-circulation mode while maintaining a ratio of the gas fed to the reaction vessel to gas leaving the reaction vessel of from 0.99:1 to 0.4:1.
摘要:
In a process for preparing aliphatic alcohols by hydrogenating aliphatic carboxylic acids or anhydrides or esters thereof or lactones in the presence of a catalyst comprising Pt and Re, in the form of the metal or an oxide in each case, the catalyst further comprises at least one further element from the groups 5 to 12 and 14 and the lanthanides of the Periodic Table of the Elements in the form of the metal or an oxide.
摘要:
A process for hydrogenating polyenes, especially 1,5,9-cyclododecatriene, to the corresponding monoenes, especially cyclododecene, using homogeneous ruthenium catalysts comprises hydrogenating in the presence of a carboxylic acid, advantageously a C1-C20 monocarboxylic acid, a C2-C6 dicarboxylic acid, cyclohexylcarboxylic acid, benzoic acid, terephthalic acid, phthalic acid or phenylacetic acid, especially acetic acid, propionic acid, succinic acid or adipic acid or a C12-C20 fatty acid. The homogeneous ruthenium catalyst is advantageously generated in situ prior to the hydrogenation. The in situ generation is carried out in the additional presence of CO or formaldehyde and the hydrogenation in the additional presence of triphenylphosphine.
摘要:
A process for preparing tetrahydrofuran, which comprises reacting 1,4-butenediol diethers of the formulae I and/or II RO—CH2—CH═CH—CH2—OR I RO—CH2—CH2═CH—CH2—OR II, where the R radicals can be identical or different and are C1-C15-alkyl or cycloalkyl radicals, C6-C12-aryl radicals or C7-C15-aralkyl radicals, with water and hydrogen at from 20 to 300° C. under from 1 to 300 bar in the presence of catalysts or catalyst combinations which comprise components which are both capable of hydrogenation and have acidic or basic centers and a novel process for preparing 1,4-butanediol diethers of the formula I by metathesis are described.
摘要:
A process for preparing cyclopentyl formates of the formula (II) ##STR1## by reacting cyclopentenes of the formula (I) ##STR2## where R.sup.1, R.sup.2 and R.sup.3, independently of one another, are hydrogen atoms or C.sub.1-8 -alkyl,with formic acid in the presence of an acid catalyst.
摘要:
A process for the preparation of .gamma.-butyrolactone, in which 2,5-dihydrofuran or 2,3-dihydrofuran or a mixture of these two dihydrofurans is caused to react in the gas phase in the presence of water and in the presence or absence of additional hydrogen at elevated temperature over a hydrogenating catalyst.
摘要:
A process for the preparation of polyoxyalkylene glycols or polyoxyalkylene glycol copolymers from polyoxyalkylene glycol formates or the formates of polyoxyalkylene glycol copolymers comprises reacting the formates of polyoxyalkylene glycols or of polyoxyalkylene glycol copolymers in the liquid phase in the presence of a heterogeneous catalyst which contains, as catalytically active component, rhenium and/or at least one element from sub-group VIII of the Periodic Table of the Elements.
摘要:
The process relates to a process for preparing delta-valerolactone (VLO) in the gas phase by catalytic dehydrogenation over at least two different catalysts.