Basf Aktiengesellschaft

Basf Se Corporation

Gerold Braun

Alfred Oftring

Thomas Greindl

Christos Vamvakaris

Friedrich Wirsing

Rolf Fikentscher

Jochen Wild

Armin Stamm

Juergen Detering

Birgit Potthoff-Karl

Guenter Oetter

Chung-Ji Tschang

Klaus Glaser

Arnulf Lauterbach

Rainer Rahm

Georg Schuh

Wolfgang Siegel

Johannes Perner

Kai-Uwe Baldenius

Klaus Mundinger

Dagmar Pascale Kunsmann-Keitel

Reinhold Kohlhaupt

Georg Krug

Werner Bochnitschek

Hans-Ulrich Jaeger

Ulrich Kaluza

Gunter Scherhag

Chung-Ji Ischang

Maxim Weber

Ingo M&uuml;nster

A process is proposed for the preparation of a crystalline L-MGDA trialkali metal salt by crystallization from an aqueous solution thereof which has been obtained by Strecker synthesis, starting from L-&#x3b1;-alanine, by reaction with formaldehyde and hydrocyanic acid to give L-&#x3b1;-alanine-N,N-diacetonitrile and subsequent alkaline saponification of the L-&#x3b1;-alanine-N,N-diacetonitrile to give the L-MGDA trialkali metal salt, wherein a temperature of 150&#xb0; C. is not exceeded during the alkaline saponification.

Process for the preparation of a crystalline L-MGDA trialkali metal salt

A process for preparing an aqueous solution of a methylglycine-N,N-diacetic acid trialkali metal salt at a high yield and purity by Strecker synthesis, the process including: reacting an aqueous solution containing &#x3b1;-alanine with formaldehyde and hydrocyanic acid, to obtain &#x3b1;-alanine-N,N-diacetonitrile in one reaction unit; and saponification of the &#x3b1;-alanine-N,N-diacetonitrile with a base, to obtain the methylglycine-N,N-diacetic acid trialkali metal salt, wherein the &#x3b1;-alanine is partially neutralized and the addition of formaldehyde and hydrocyanic acid are controlled such that a concentration of free hydrocyanic acid in the liquid reaction mixture at any time is limited such that secondary reactions that produce formaldehyde cyanohydrin, consecutive reactions of formaldehyde cyanohydrin, and the polymerization of hydrocyanic acid, only occur insofar as the specification requirements, such as nitrilotriacetic acid content and color, for methylglycine-N,N-diacetic acid trialkali metal salts are observed.

Process for the preparation of aqueous solutions of methylglycine-N,N-diacetic acid trialkali metal salts

Provided is a method for the production of aminodicarboxylic acid N,N-diacetic acids of formula (I), wherein X is independently hydrogen or an alkali metal and n is 1 or 2. Aminodicarboxylic acid-N,N-diacetic acids of high purity can be yielded. The method involves: a) reacting an aminodicarboxylic acid, with 0.8 to 1.2 mole equivalents of formaldehyde and with 0.8 to 1.2 mole equivalents of hydrocyanic acid; b) reacting the reaction products of a) with 0.8 to 1.2 mole equivalents of hydrocyanic acid and with 0.8 to 1.2 mole equivalents of formaldehyde; c) hydrolyzing in the reaction product obtained in b).

Method for the production of aminodicarboxylic acid-N,N-diacetic acids

The invention relates to a process for preparing low-by-product, light-color methylglycine-N,N-diacetic acid tri(alkali metal) salt by alkaline hydrolysis of methylglycinediacetonitrile (MGDN), comprising the steps in the sequence (a) to (f):

Method for producing methylglycine-N,N-diethanoic acid-trialkali metal salts with a low by-product content

The present invention relates to a process for preparing 3-cyano-3,5,5-trimethylcyclohexanone (isophoronenitrile) by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst to obtain a crude isophoronenitrile product, and subsequently distilling the crude isophoronenitrile product, with the addition before distillation of at least one specific sulfonic acid or specific carboxylic acid. In addition, the present invention relates to the use of a specific sulfonic acid or of a specific carboxylic acid as a neutralizing agent before distillation of a crude isophoronenitrile product which has been obtained by reacting isophorone with hydrogen cyanide in the presence of a base as a catalyst, in order to avoid precipitates in the neutralization of the base used as a catalyst with an acid.

Neutralization of isophorone nitrile synthesis products

The invention relates to a continuous process, carried out in two steps, for the cyanoalkylation of compounds having one or more NH functions by reaction thereof with carbonyl compounds and hydrocyanic acid, in which the first step is carried out without pressure at a temperature which is below the boiling point of the reaction mixture.

Continuous process for the cyanoalkylation of compounds having one or more NH functions

The present invention describes a process for preparing isophoronenitrile by adding HCN to isophorone. The catalyst used is CaO which has a BET surface area of >1.5 m /g. The use of such a catalyst achieves high yields and selectivities.

CaO-catalyzed preparation of isophoronenitrile

Method for producing long-chain glycine-N,N-diacetic acid derivatives

A process for preparing compounds of the formula IIb

Glycine-N,N-diacetic acid derivatives I ##STR1## where R is unsubstituted or substituted alkyl, alkenyl, alkoxylate groups, phenylalkyl, phenyl, a heterocyclic ring or a radical of the formula ##STR2## where A is an alkylene bridge or a chemical bond, and M is hydrogen, alkali metal, alkaline earth metal, ammonium or substituted ammonium in the appropriate stoichiometric amounts, are prepared by reacting

Preparation of glycine-N,N-diacetic acid derivatives

Glycine-N, N-diacetic acid derivatives are prepared by reacting corresponding 2-substituted glycines, 2-substituted glycinonitriles, doubled glycines, or precursors of the glycine derivatives with formaldehyde and alkali metal cyanide. The reaction is conducted in an aqueous medium at a pH of 8 to 14. From 0, 5 to 30% of the amount of alkali metal cyanide required for the reaction are added to the glycine derivatives or precursors thereof Subsequently, the remaining amount of alkali metal cyanide and the formaldehyde are simultaneously metered in over a period of from 0.5 to 12 hours.

Process for the preparation of glycine-N, N-diacetic acid derivatives

Pulverulent or water-free liquid detergents each essentially contain surfactants, builders, bleaching agents and effective amounts of compounds of the formula ##STR1## where R.sup.1 is for example C.sub.1 -C.sub.8 -alkyl, substituted or unsubstituted alkyl or C.sub.3 -C.sub.8 -alkenyl, and R.sup.2 and R.sup.3 are each for example H or C.sub.1 -C.sub.16 -alkyl, as bleach activators for peroxides.

Detergents that contain acyl derivatives of dihydroxydioxane as bleach

Specific sulfonamidocarboxylic acids in the form of the alkali metal or alkanolamine salts are used as corrosion inhibitors in aqueous systems.

Use of salts of sulfonamidocarboxylic acids as corrosion inhibitors in

Sulfatobetaines are prepared by reacting an addition compound of sulfur trioxide and a tertiary amine with an alkylene carbonate.

Preparation of sulfatobetaines

Sulfatobetaines are prepared by reacting an adduct of a base having a tertiary N atom and sulfur trioxide with an alkylene oxide in the presence of an alkylene carbonate as a solvent.

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Ludwigshafen, Germany

Gerold Braun