Abstract: The invention relates to an apparatus and a process for the preparation of anhydrous or substantially anhydrous formic acid. This apparatus is constructed partly or entirely of substantially zirconium-free materials. The extractant employed is a liquid of the general formula I where the radicals R1 and R2 are alkyl, cycloalkyl, aryl or aralkyl groups, or R1 and R2 jointly, together with the N atom, form a heterocyclic 5- or 6-membered ring, and only one of the radicals is an aryl group, and where R3 is hydrogen or a C1–C4-alkyl group. The apparatus has a synthesis reactor (6), a hydrolysis reactor (1), three distillation devices (2,4,5) and an extraction device (3).

Abstract: A process for working up a liquid reaction discharge of the cationic polymerization of isobutene, which substantially comprises polyisobutene, unconverted isobutene and, if required, an inert diluent, is described. Problems with foam formation when the unconverted isobutene is being distilled off are avoided if the heated reaction discharge is let down into a flash container and/or not more than 900 m3/h of vapor are expelled per square meter of liquid surface and/or the resulting foam is destroyed, for example in a wet cyclone.

Abstract: A polyisobutene composition having a global maximum of the differential molecular weight distribution curve at a molecular weight Mmax of from 3 500 to 8 000 is described, which comprises at least one local maximum at a molecular weight of from 112 to 560. The isobutene oligomers present act as flow improvers and boiling assistants. They are added to higher molecular weight isobutene polymers, preferably before or in the course of a distillation, for removing unconverted isobutene and/or an inert diluent.

Abstract: A process for working up a liquid reaction discharge of the cationic polymerization of isobutene, which substantially comprises polyisobutene, unconverted isobutene and an inert diluent, in which the reaction discharge is heated and is let down into a flash container, is described, the reaction discharge separating, as a result of the flashing, into a polyisobutene-containing liquid phase and a gas phase containing the main amount of the isobutene contained in the reaction discharge and of the diluent.

Abstract: A process for the preparation of highly reactive polyisobutenes is described, in which isobutene is polymerized in the presence of a complex of boron trifluoride and at least one cocatalyst in a liquid organic phase at a reaction temperature of from ?60 to ?4° C. and water is added in two stages to the organic phase for catalyst deactivation and catalyst extraction.

Abstract: A description is given of a process for preparing methyl formate by reacting excess methanol with carbon monoxide under superatmospheric pressure and at elevated temperature in the presence of alkali metal methoxide or alkaline earth metal methoxide as catalyst in a pressure-rated reactor, in which the use of at least two reactor elements, preferably operated in countercurrent, at about 100° C. and a pressure of about 100 bar in combination with a solids-free desalting of the reaction product makes possible very economical, largely trouble-free production of methyl formate in any desired quality and with a very good production capacity. Furthermore, the process for solids-free desalting and apparatuses for carrying out this process are described.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid, in which firstly aqueous formic acid is prepared by hydrolysis of methyl formate and is freed from water in the subsequent work-up. The process has the special feature that steam, which is employed for the hydrolysis of methyl formate and for heating a distillation column serving for work-up, is also used as stripping steam for waste-water stripping. The stripped waste water is produced during work-up.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid, in which firstly aqueous formic acid is produced by hydrolysis of methyl formate, with the methanol content in the methyl formate having been reduced in advance. The process according to the invention has the special feature that—before the hydrolysis of the methyl formate—the methanol content of the methanol-containing methyl formate is reduced in a distillation column, this distillation column simultaneously being employed for other separation functions during work-up of the formic acid.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid in which, during the work-up, a compound of the general formula I where the radicals R1 and R2 are alkyl, cycloalkyl, aryl or aralkyl groups, or R1 and R2 jointly, together with the N atom, form a heterocyclic 5- or 6-membered ring, and only one of the radicals is an aryl group, and where R3 is hydrogen or a C1-C4-alkyl group, is employed simultaneously as extractant for formic acid and as antifoam for a distillation process.

Abstract: In a process for purification of ethylene oxide by distillation an aqueous mixture comprising ethylene oxide, formaldehyde and at least 5% by weight of water is introduced via a feed into a distillation apparatus comprising at least one distillation column, the mixture being introduced at a height above the bottom of at least 8 theoretical stages, the ethylene oxide is taken off at the top and in the bottom phase a mixture is obtained which contains less than 5% by weight of ethylene oxide.

Abstract: A polyisobutene composition having a global maximum of the differential molecular weight distribution curve at a molecular weight Mmax of from 3 500 to 8 000 is described, which comprises at least one local maximum at a molecular weight of from 112 to 560. The isobutene oligomers present act as flow improvers and boiling assistants. They are added to higher molecular weight isobutene polymers, preferably before or in the course of a distillation, for removing unconverted isobutene and/or an inert diluent.

Abstract: A process for working up a liquid reaction discharge of the cationic polymerization of isobutene, which substantially comprises polyisobutene, unconverted isobutene and, if required, an inert diluent, is described. Problems with foam formation when the unconverted isobutene is being distilled off are avoided if the heated reaction discharge is let down into a flash container and/or not more than 900 m3/h of vapor are expelled per square meter of liquid surface and/or the resulting foam is destroyed, for example in a wet cyclone.

Abstract: A process for working up a liquid reaction discharge of the cationic polymerization of isobutene, which substantially comprises polyisobutene, unconverted isobutene and an inert diluent, in which the reaction discharge is heated and is let down into a flash container, is described, the reaction discharge separating, as a result of the flashing, into a polyisobutene-containing liquid phase and a gas phase containing the main amount of the isobutene contained in the reaction discharge and of the diluent.

Abstract: The invention relates to a process for the preparation of anhydrous or substantially anhydrous formic acid. The process has the special feature that a liquid of the general formula I where the radicals R1 and R2 are alkyl, cycloalkyl, aryl or aralkyl groups, or R1 and R2 jointly, together with the N atom, form a heterocyclic 5- or 6-membered ring, and only one of the radicals is an aryl group, and where R3 is hydrogen or a C1-C4-alkyl group, employed as extractant is also employed as washing liquid for the offgases produced in the process.

Abstract: Connecting element (1) for connecting two components of a partition wall, comprising two clamping flanges (2,3) interconnected by a connecting rod (4). Said element has an asymmetric configuration due to the fact that the clamping flanges (2,3) have different cross sections. At least parts of the contour of the first clamping flange (2) are unrounded while at least certain parts of the contour of the second clamping flange (3) are rounded.

Abstract: The invention relates to an apparatus and a process for the preparation of anhydrous or substantially anhydrous formic acid. This apparatus is constructed partly or entirely of substantially zirconium-free materials.

Abstract: The invention relates to a process for the preparation of anhydrous or substantially anhydrous formic acid.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid, in which firstly aqueous formic acid is prepared by hydrolysis of methyl formate and is freed from water in the subsequent work-up. The process has the special feature that steam, which is employed for the hydrolysis of methyl formate and for heating a distillation column serving for work-up, is also used as stripping steam for waste-water stripping. The stripped waste water is produced during work-up.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid, in which firstly aqueous formic acid is produced by hydrolysis of methyl formate, with the methanol content in the methyl formate having been reduced in advance. The process according to the invention has the special feature that—before the hydrolysis of the methyl formate—the methanol content of the methanol-containing methyl formate is reduced in a distillation column, this distillation column simultaneously being employed for other separation functions during work-up of the formic acid.

Abstract: The invention relates to a process for obtaining anhydrous or substantially anhydrous formic acid in which, during the work-up, a compound of the general formula I 1