Abstract: There is disclosed an improved process for preparing 1-hydroxy-3-oxa-1,2,4,5-pentane tetracarboxylic acid and 3,6-dioxa-1,2,4,5,7,8-octane hexacarboxylic acid wherein the unreacted starting acids are recovered in more desirable crystal habit. The acids are precipitated in salt form by lowering the pH of the reaction product to a range of from 4 to below 6 stepwise. The pH is lowered to above 6 in the first step and then relatively rapidly reduced to the desired level in the second step.
Type:
Grant
Filed:
August 24, 1988
Date of Patent:
August 21, 1990
Assignee:
Monsanto Company
Inventors:
Edward J. Griffith, Liou-Liang Horng, Mark E. Jason
Abstract: A method of disposing of wastes containing heavy metal compounds by neutralizing the wastes, oxidizing the neutralized wastes, then solidifying the oxidized wastes using conventional mineral binding agents such as Portland cement. This method is of particular interest in treating arsenic sulfide containing aqueous sludges produced in the manufacture of phosphoric acid.
Abstract: A method of forming condensed phosphates comprising reacting phosphate ions, such as generated from polyphosphate salts, and sulfamides, in an aqueous solution or suspension. An example of such a reaction is the reaction of tetrasodium tripolyphosphate and sulfamide in water to form sodium trimetaphosphate.
Abstract: A method for preparation of solid particulate polyacetal carboxylate. The method comprises agglomerating a solution comprising less than about 1% by weight methanol and between about 30% by weight and about 60% by weight polyacetal carboxylate onto a substrate to produce a free-flowing particulate solid. The solid comprises between about 30% by weight and about 55% by weight polyacetal carboxylate. The polyacetal carboxylate corresponds to the formula: ##STR1## where n is at least about 4 and represents the average chain length of the polyacetal carboxylate in the mixture, R.sub.1 and R.sub.2 are independently selected chemically stable groups that stabilize the polymer against rapid depolymerization in alkaline solution, and M is selected from the group consisting of alkali metals, ammonium, alkyl groups of 1 to about 4 carbon atoms, tetraalkyl ammonium groups, and alkanolamine groups having from 1 to about 4 carbon atoms in the alkyl chain.
Type:
Grant
Filed:
February 8, 1988
Date of Patent:
June 13, 1989
Assignee:
Monsanto Company
Inventors:
David A. Martin, Edward L. Ries, William Vanderlinde, Marvin J. Young
Abstract: An energy saving process for preparing N,N-diacetic acid aminomethylenephosphonic acid by reacting an alkali metal salt of iminodiacetic acid in aqueous strong mineral acid solution with phosphorous acid and formaldehyde and then adding sufficient water to dissolve the alkali metal salt formed during the reaction. The desired product is recovered as a precipitate from the solution.
Abstract: An energy saving process for preparing N,N-diacetic acid aminomethylenephosphonic acid by reacting an alkali metal salt of iminodiacetic acid in aqueous strong mineral acid solution with phosphorous acid and formaldehyde and then adding sufficient water to dissolve the alkali metal salt formed during the reaction. The desired product is recovered as a precipitate from the solution.
Abstract: Maleate polymers and derivatives of maleate polymers containing specified functional groups are effective scale inhibitors, for calcium phosphate scale.
Type:
Grant
Filed:
November 13, 1985
Date of Patent:
June 16, 1987
Assignee:
Monsanto Company
Inventors:
James P. Coleman, George Kvakovszky, David J. Sikora
Abstract: This disclosure relaes to arylsulfenyl derivatives of benzyl and aryl esters of N-phosphonomethylglycines. This disclosure further relates to herbicidal compositions containing arylsulfenyl derivatives of benzyl and aryl esters of N-phosphonomethylglycines, to the use thereof, and to herbicidal methods employing such compounds and compositions.
Abstract: A process for the preparation of a glyphosate product. An .alpha.-substituted N-phosphonomethylamino diacetic acid substrate is contacted in an aqueous medium with molecular oxygen in the presence of a catalyst for the oxidative cleavage of a substituent from the imino nitrogen of the substrate. Cleavage produces a glyphosate product, carbon dioxide, a higher aldehyde, or ketone. Novel intermediates and methods of preparation thereof are also disclosed.
Abstract: There is disclosed a process for the preparation of N-phosphonomethylglycine by dealkylation of N-alkyl-N-phosphonomethylglycine. The N-alkyl moiety contains an electron withdrawing group in the 2-position. Certain novel N-alkyl-N-phosphonomethylglycines are disclosed.
Abstract: Compounds of the formula ##STR1## wherein x is NH and wherein R.sub.1 is selected from branched-chain lower alkyl, alkoxyalkyl, alkylthioalkyl, cycloalkyl, and cycloalkanylalkyl radicals, R.sub.2 is a C.sub.1-4 alkyl radical and R.sub.3 represents a C.sub.1-4 fluoroalkyl radical are disclosed as herbicides.
Abstract: A process for the preparation of a glyphosate product. An .alpha.-substituted N-phosphonomethylamino diacetic acid substrate is contacted in an aqueous medium with molecular oxygen in the presence of a catalyst for the oxidative cleavage of a substituent from the imino nitrogen of the substrate. Cleavage produces a glyphosate product, carbon dioxide, a higher aldehyde, or ketone. Novel intermediates and methods of preparation thereof are also disclosed.
Abstract: Processes are described wherein formaldehyde or formic acid and similar materials are oxidized to produce carbon dioxide and water by contact with oxygen in the presence of a noble metal catalyst on a carbon support that is protected from poisonous amines by a polymer coating.
Type:
Grant
Filed:
February 11, 1985
Date of Patent:
April 1, 1986
Assignee:
Monsanto Company
Inventors:
Arnold Hershman, David E. Gross, Robert M. Friedman
Abstract: A process for preparing glyphosate and derivatives of related structure. A precursor primary or secondary amine, such as glycine, is condensed with a carbonyl compound, such as formylphosphonic acid or its acetals, and the condensation product is reduced to produce the desired product.
Abstract: This invention relates to a process for preparing sulfenyl chloride derivatives of N-phosphonomethylglycinonitriles which are useful as herbicides or as intermediates for the production of thiosulfenamide derivatives of N-phosphonomethylglycinonitriles which are useful as herbicides.
Abstract: A process for producing nitrilotriacetate salts from nitrilotriacetonitrile in which a mixture of substantially stoichiometric amounts of an alkali metal hydroxide and nitrilotriacetonitrile in water are partially hydrolyzed, followed by boiling to complete the reaction, followed by addition of a bleaching agent, and recovery of the product as a solution or in crystalline form.
Abstract: This invention relates to unsymmetrical aminosulfinamide derivatives of N-phosphonomethyl-glycine triesters which are useful as herbicides. This invention further relates to herbicidal compositions containing such derivatives and to herbicidal methods employing such compounds and compositions.
Abstract: This invention relates to a process for preparing sulfenyl chloride derivatives of N-phosphonomethylglycinonitriles which are useful as herbicides or as intermediates for the production of thiosulfenamide derivatives of N-phosphonomethylglycinonitriles which are useful as herbicides.