摘要:
A binder-consolidated cellulose bead or lignocellulose bead (referred to as consolidated bead for short), obtainable by mixing of cellulose or lignocellulose beads with a binder and subsequent crosslinking of the binder.
摘要:
A catalyst for the hydrogenation of C4-dicarboxylic acids and/or their derivatives, preferably maleic anhydride, in the gas phase comprises from 5 to 100% by weight, preferably from 40 to 90% by weight, of copper oxide and from 0 to 95% by weight, preferably from 10 to 60% by weight, of one or more metals or compounds thereof selected from the group consisting of Al, Si, Zn, Pd, La, Ce, the elements of groups III A to VIII A and groups I A and II A as active composition applied in the form of a thin layer to an inert support material.
摘要:
In a process for preparing alcohols by catalytic hydrogenation of carbonyl compounds over a catalyst comprising rhenium on activated carbon, the catalyst used comprises rhenium (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5, platinum (calculated as metal) in a weight ratio to the activated carbon of from 0.0001 to 0.5 and, if appropriate, at least one further metal selected from among Zn, Cu, Ag, Au, Ni, Fe, Ru, Mn, Cr, Mo, W and V in a weight ratio to the activated carbon of from 0 to 0.25, and the activated carbon has been nonoxidatively pretreated. It is also possible to prepare ethers and lactones if the hydrogen pressure is not more than 25 bar. In this case, the activated carbon in the catalyst may also have been nonoxidatively pretreated.
摘要:
A process for the preparation of 1,6-hexanediol and 6-hydroxycaproic acid or esters thereof by catalytic hydrogenation of adipic acid, adipic acid monoesters or adipic acid diesters or streams of starting material which contain adipic acid or esters thereof as essential constituents, in which the bottom product obtained in the distillation of the hydrogenation product, following removal of the hexanediol and hydroxycaproic acid or esters thereof, and essentially comprises oligomeric esters of 6-hydroxycaproic acid, is recycled to the hydrogenation, and the resulting mixture of starting material and recycle stream is reacted at from 100 to 300°C., at from 10 to 300 bar in the liquid phase and at a molar ratio of carboxyl groups to be hydrogenated to hydrogen in the reactor of from 1:5 to 1:100 on hydrogenation catalysts is described.
摘要:
A process for preparing cyclopentanone and cyclopentene-1-carboxylic acid or an ester thereof of the formula I where R is hydrogen or an aliphatic radical having 1-6 carbon atoms or a cycloaliphatic, araliphatic or aromatic radical having 6-12 carbon atoms comprises heating a compound of the formula II X—(CH2)4—COOR II where X is formyl or hydroxymethyl and R is defined as above, and/or a compound which is converted into a compound of the formula II by reaction with water or alcohols ROH under the reaction conditions to from 200 to 450° C. in the gas or liquid phase in the presence of a heterogeneous oxidic catalyst.