摘要:
Methacrolein is removed from a gaseous mixture by absorption by means of an aqueous solution which contains from 60 to 90% by weight of methacrylic acid.
摘要:
A process for obtaining pure 1,3-butadiene from crude 1,3-butadiene by distillation is carried out in a dividing wall column in which a dividing wall is located in the longitudinal direction of the column to form an upper common column region, a lower common column region, a feed section and an offtake section.
摘要:
A process for the single-stage preparation of polytetrahydrofuran and/or tetrahydrofuran copolymers having a mean molecular weight of from 650 to 5000 dalton by polymerization of tetrahydrofuran over a heterogeneous acid catalyst in the presence of at least one telogen and/or comonomer selected from the group consisting of alpha,omega-diols, water, polytetrahydrofuran having a molecular weight of from 200 to 700 dalton and cyclic ethers comprises a) separating off the catalyst and/or downstream products of the catalyst suspended and/or dissolved in the output from the polymerization, b) fractionating the resulting catalyst-free output from the polymerization in at least one distillation step to give a distillation residue comprising the polymerization product and at least one tetrahydrofuran fraction and returning at least part of the tetrahydrofuran fraction to the polymerization and c) separating low molecular weight polytetrahydrofuran and/or tetrahydrofuran copolymers having a mean molecular weight of from 200 to 700 dalton from the distillation residue from work-up step b) and isolating polytetrahydrofuran and/or tetrahydrofuran copolymers having a mean molecular weight of from 650 to 5000 dalton.
摘要:
A process for recovering crude 1,3-butadiene from a C4 fraction by extractive distillation using a selective solvent in a dividing wall column (TK) in which a dividing wall (T) is arranged in the longitudinal direction of the column to form a first subregion (A), a second subregion (B) and a lower common column region (C) and which is preceded by an extractive scrubbing column (K) is proposed.
摘要翻译:通过在分隔壁(T)中分离壁(T)纵向配置的分隔壁塔(TK)中的选择性溶剂进行萃取蒸馏,从C 4 H 4馏分中回收粗1,3-丁二烯的方法, 提出了列的方向以形成第一子区域(A),第二子区域(B)和下共同列区域(C),并且之前是抽取洗涤列(K)。
摘要:
The invention relates to a catalyst which contains a catalytically active quantity of at least one oxygen-containing molybdenum and/or wolfram compound on an oxidic support material and which has been calcinated at temperatures of 400 to 900° C. after the precursor compound of the catalytically active compounds have been applied to the support material or to a support material precursor. The transport pores for this catalyst each have a diameter of >25 nm and a volume of at least 50 mm3/g. The catalyst contains x μmol (wolfram and/or molybdenum)/m2 molybdenum and/or wolfram, with 10.1
摘要翻译:本发明涉及一种催化剂,其在氧化载体材料上含有至少一种含氧钼和/或钨化合物的催化活性量,并且在400-900℃的温度下煅烧之后, 催化活性化合物已经施加到载体材料或载体材料前体上。 该催化剂的输送孔各自具有> 25nm的直径和至少50mm 3 / g的体积。 该催化剂含有xmumol(钨和/或钼)/ m 2钼和/或钨,相对于成品催化剂为10.1