Abstract: The invention relates to a pipe (13) for conveying a condensable gas or a gas comprising condensable components, comprising at least one portion (15) inclined relative to horizontal. A ring (17) is accommodated in the portion (15) inclined relative to horizontal, which ring is joined to the pipe (13) by a first end face (21) in a liquid-tight manner over its entire circumference and whose diameter decreases towards a second end face (25) opposite the first end face (21), such that a space (27) is formed between the ring (17) and the internal wall of the pipe (13), the ring (17) is positioned in such a way in the pipe (13) that liquid condensing on the pipe wall flows into the space (27) between ring (17) and internal wall of the pipe (13), and an outlet (19), through which the liquid may flow out, opens into the space (27) through the wall of the pipe (13). The invention further relates to a device for carrying out mass transfer processes and to use of the device.

Abstract: A process for preparing nitric acid by: catalytically oxidizing ammonia, to obtain a gas mixture containing NO and O2; cooling and condensing the gas mixture, thereby further oxidizing NO with O2, to obtain a gas stream containing NO2/N2O4 and an aqueous solution containing nitric acid; and countercurrently absorbing the NO2/N2O4 from the gas stream in an absorber with process water (H2O), to obtain nitric acid and an NOx-containing absorber offgas, wherein the water content of the nitric acid is regulated to a concentration in the range from 50 to 77.8% by weight and the NOx content of the absorber offgas to a concentration in the range from 20 to 500 ppm, by continuously measuring the water content of the process air supplied to the catalytic gas phase oxidation and, as a function of this, adjusting the amount of process water (Q-H2O) fed to the absorber.

Abstract: What is proposed is a process for preparing nitric acid with a concentration in the range from 50 to 77.8% by weight by catalytic gas phase oxidation of ammonia (1) with a superstoichiometric proportion of process air (2) to obtain a gas mixture (3) comprising NO and O2, cooling/condensation of the gas mixture (3) comprising NO and O2, in the course of which NO is oxidized further by O2 to NO2/N2O4 to obtain an aqueous solution (4) comprising nitric acid and a gas stream (5) comprising NO2/N2O4 and countercurrent absorption of the NO2/N2O4 from the gas stream (5) comprising NO2/N2O4 in process water (H2O) in an absorber (A) to obtain the nitric acid (7) with a concentration in the range from 50 to 77.8% by weight and an NOx comprising absorber offgas (6), wherein the water content of the nitric acid (7) is regulated to a concentration in the range from 50 to 77.

Abstract: A method is provided for the intrinsically safe handling of 3-chloropropyne in the presence of a diluent with a boiling point ranging from ?50° C. (223 K) to 200° C. (473 K) under atmospheric pressure, wherein the concentration of 3-chloropropyne in the liquid phase and in the gas phase is kept below the concentrations capable of deflagration by means of the type and amount of the diluent, the temperature and the total system pressure, together with the use of a 3-chloropropyne prepared, stored or transported in this way in the synthesis of dyestuffs, pharmaceutical and agricultural active ingredients, electroplating auxiliaries, disinfectants, steroids and growth hormones.

Abstract: The invention relates to a method for producing the tautomeric form (I) of 2,4,6-trianilino-p-(carbo-2?-ethylhexyl-1?-oxy)-1,3,5-triazine by the crystallization of a tautoner mixture in the presence of one or more solvents selected from the group consisting of aliphatic alcohol having 2 8 C-atoms made of aliphatic alcohol, aliphatic carboxylic acid alkyl esters having a total of between 3–10 C-atoms, aromatic carboxylic acid alkyl esters having a total of between 8–12 C-atoms, aliphatic carboxylic acid esters having a total of between 3 9 C-atoms, carboxylic acid nitriles having a total of between 2–8 C-atoms, dialkylketones having a total of between 3–6 C-atoms and aliphatic sulphones having a total of between 3–6 C-atoms. The solvent or solvent mixture can additionally contain up to 30 wt % of a hydrocarbon (I) acts as a light protecting agent in cosmetic preparations.

Abstract: Process for the preparation of the tautomeric form I of 2,4,6-trianilino-p-(carbo-2?-ethylhexyl-1?-oxy)-1,3,5-triazine by crystallization from a tautomer mixture in the presence of one or more solvents chosen from the group consisting of aliphatic alcohols having 2 to 8 carbon atoms, aliphatic carboxylic alkyl esters having a total of 3 to 10 carbon atoms, aromatic carboxylic alkyl esters having a total of 8 to 12 carbon atoms, aliphatic carbonic esters having a total of 3 to 9 carbon atoms, carbonitriles having a total of 2 to 8 carbon atoms, dialkyl ketones having a total of 3 to 6 carbon atoms and aliphatic sulfones having a total of 3 to 6 carbon atoms, where the solvent or the solvent mixture may additionally comprise up to 30% by weight of a hydrocarbon. I is used as light protection agent in cosmetic preparations.

Abstract: A process for preparing &bgr;-alkoxynitriles by reacting &agr;,&bgr;-unsaturated nitriles with monohydric, dihydric or trihydric alcohols in the presence of basic catalysts at from −20 to +200° C. comprises using a diazabicycloalkene catalyst of the formula I where from 1 to 4 hydrogen atoms may be independently replaced by the radicals R1 to R4, in which case R1, R2, R3, R4 are each C1-20-alkyl, C6-20-aryl or C7-20-arylalkyl, and n and m are each an integer from 1 to 6.

Abstract: The invention relates to a method for producing acid chlorides by converting carboxylic acids with carbon oxychlorides or thionyl chloride in the presence of a catalyst adduct of an N,N-disubstituted formamide of general formula (I) and carbon oxychloride or thionyl chloride. In the formula, R1 and R2, independently from one another, mean C1- to C4-alkyl or R1 and R2 together mean a C4- or C5-alkylene chain. According to the inventive method, hydrogen chloride is added during and/or after the conversion.

Abstract: A method is provided for the intrinsically safe handling of 3-chloropropyne in the presence of a diluent with a boiling point ranging from −50° C. (223 K) to 200° C. (473 K) under atmospheric pressure, wherein the concentration of 3-chloropropyne in the liquid phase and in the gas phase is kept below the concentrations capable of deflagration by means of the type and amount of the diluent, the temperature and the total system pressure, together with the use of a 3-chloropropyne prepared, stored or transported in this way in the synthesis of dyestuffs, pharmaceutical and agricultural active ingredients, electroplating auxiliaries, disinfectants, steroids and growth hormones.

Abstract: The invention relates to a method for producing o-choromethyl benzenecarbonyl chlorides of formula (I), wherein R1-R4 can be the same or different and stand for hydrogen, C1-C4-alkyl, halogen or trifluoromnethyl, by converting benzocondensed lactones of formula (II), wherein R1-R4 have the aforementioned meaning, with gaseous or liquid phosgene and the dimers or trimers thereof.

Abstract: Process for the purification of carbonyl chlorides which have been prepared by reacting carboxylic acids with phosgene or thionyl chloride in the presence of a catalyst adduct, in which the carbonyl chlorides are treated with a hydrohalide of carboxamides of the formula (I) in which R1 is hydrogen or C1- to C3-alkyl; R2 and R3 independently of one another are C1- to C4-alkyl, or R2 and R3 together are a C4- or C5-alkylene chain, and the carbonyl chloride purified in this way is isolated by separation off from the carboxamide hydrohalide phase.

Abstract: The present invention relates to a process for the preparation of aliphatic, cycloaliphatic, araliphatic and aromatic mono- and oligoisocyanates by phosgenation of the corresponding primary amines at atmospheric pressure, which comprises a) introducing a catalytic amount of a monoisocyanate (isocyanate a) into an inert solvent together with phosgene; b) adding the primary amine, and c) reacting the resulting reaction mixture with phosgene.

Abstract: A process for the preparation of chlorocarboxylic chlorides of formula (I) 1

Abstract: A process for preparing chlorocarbonyl chlorides of the formula (I) 1

Abstract: A process for the preparation of aldehydes or aldehydes and alcohols by hydroformylation of olefins containing more than 3 carbon atoms, comprising a hydroformylation stage, in which the olefin is hydroformylated under a pressure of form 50 to 1000 bar and at a temperature of from 50° to 180° C. by means of a rhodium catalyst dissolved in a homogenous reaction medium and a catalyst recovery stage comprising extraction of the rhodium catalyst with an aqueous solution of chelating agent, isolation of alcohols and/or aldehyde from the extracted hydroformylation product steam, precarbonylation of the aqueous rhodium-containing extract in the presence of carbon monoxide, synthesis gas as, or a gas mixture containing carbon monoxide under a pressure of from 50 to 1000 bar and at a temperature of from 50° to 180° C.

Abstract: In a process for preparing a bicyclic amidine by reacting a lactone and a diamine with elimination of water, water formed by elimination is removed from the reaction mixture during the reaction. A diazabicycloalkene, a process for its preparation and its use are also described.

Abstract: Halides are removed from halide-containing nitrile mixtures by(a) thermally treating the halide-containing nitrile mixture,(b) subsequently adding a base to the thermally treated nitrile mixture and(c) subsequently separating off the base from the nitrile mixture.Amines are prepared by(A) reacting alkyl halides with metal cyanides in an at least two-phase reaction medium in the presence of halide-containing phase-transfer catalysts to give alkanenitriles,(B) separating off the resulting halide-containing alkanenitrile mixture phase and(C) further treating the halide-containing alkanenitrile mixture phase, as described in the stages(a)-(c) removing halides from halide-containing nitrile mixtures and(d) hydrogenating nitrites obtained in stage (c) to give amines, in the presence of suspended or fixed-bed catalysts.

Abstract: In the process for preparing N-ethyldiisopropylamine by reacting acetaldehyde with diisopropylamine and hydrogen at elevated temperature and under pressure in the presence of a hydrogenation catalyst, the catalyst comprises an oxidic support material selected from the group consisting of zirconium dioxide, titanium dioxide, aluminum oxide, silicon dioxide, zinc oxide, magnesium oxide, cerium dioxide, clays and zeolites or mixtures thereof.

Abstract: A process for the preparation of aldehydes or aldehydes and alcohols by hydroformylation of olefins containing more than 3 carbon atoms comprising a hydroformylation stage, in which the olefin is hydroformylated under a pressure of from 50 to 1000 bar and at a temperature of from 50.degree. to 180.degree. C.

Abstract: A fuel or lubricant composition containing polyisobutene amines and which contains at least one secondary polyisobutene amine of the formula I, ##STR1## in which R denotes a polyisobutene radical containing from 6 to 45 isobutylene units, up to 20% of the isobutylene units being replaceable by n-butylene units, provided that the amount of the secondary polyisobutene amine is larger than the amount of any corresponding primary or tertiary polyisobutene amine which may also be present.