Robert J Grinstead

US Patent:

47552980, Jul 5, 1988

Filed:

Dec 4, 1986

Appl. No.:

6/937768

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

B01D 1300

US Classification:

210638

Abstract:

The present invention relates to a cyclic continuous process for the removal of boron ion from aqueous streams. An aqueous stream in contacted with an aqueous solution of a water-soluble organic polymeric chelant. The boron ion is absorbed and chelated. The separation of water and smaller molecules is accomplished by separation means such as ultrafiltration or dialysis. The concentrated aqueous solution is then treated with dilute aqueous mineral acid, followed by the released boron. The chelant is then recycled and reused. Preferred chelants are polymers having pendant N-alkylglucamine or derivative thereof or trihydroxyalkylamines or derivatives thereof. A preferred chelant is N-methylglucamine attached to a commercial FIBRABON 35 polymer using a -2-hydroxypropyl linkage. Additional preferred embodiments are those polymers having trihydroxymethyl amine in the pendant group attached to a FIBRABON 35 polymer backbone. The process is useful to remove toxic boron from agricultural water, industrial waters, waste-water sewage, oil well brine, and the like.

US Patent:

39807029, Sep 14, 1976

Filed:

Nov 4, 1975

Appl. No.:

5/628707

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

C07C 5148
C07C121407

US Classification:

260527R

Abstract:

Mono or dicarboxylic acids containing from two to four carbon atoms are extracted from dilute aqueous solutions with an organic liquid comprising one or more of the following extractants: dialkyl alkyl phosphonates, alkyl dialkyl phosphinates, trialkyl phosphine oxides, dialkyl alicyclic amidophosphates, dialkyl sulfoxides and tetralkyl ureas. An improved method for removing carboxylic acid contaminants from aqueous effluents or recycle streams is provided.

US Patent:

41234359, Oct 31, 1978

Filed:

Aug 25, 1977

Appl. No.:

5/827650

Inventors:

Robert R. Grinstead - Walnut Creek CA
Kenneth C. Jones - Walnut Creek CA
Wilmonte A. Nasutavicus - Lafayette CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

C07D26356

US Classification:

260307D

Abstract:

Nitro-substituted 2-(2-hydroxyphenyl)benzoxazoles of the formula ##STR1## wherein one of R. sup. 3 and R. sup. 4 is --NO. sub. 2 and the other is --H, --NO. sub. 2 or alkyl of 1 to 20 carbons and R. sup. 1 and R. sup. 2 independently are --H or alkyl of 1 to 20 carbons, with the proviso that R. sup. 1, R. sup. 2, R. sup. 3 and R. sup. 4 contain a total of at least 7 carbons, are acidic, oil soluble compounds having utility for extraction of copper from strongly acidic ore leaches. Excellent selectivity for copper over iron is exhibited by the subject compounds.

US Patent:

43828728, May 10, 1983

Filed:

Sep 8, 1980

Appl. No.:

6/184828

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Co. - Midland MI

International Classification:

C22B 300
C07F 1702
C01G 4900

US Classification:

252189

Abstract:

An extractant system comprising (a) a high molecular weight alkylaromatic sulfonic acid and (b) a chelating amine having a pKa of from about 3 to about 9 in a solvent which is essentially immiscible with water, said system being useful for the selective extraction of desired metals, e. g. , cobalt, nickel or copper ions from aqueous acidic ore leach liquors.

US Patent:

44513755, May 29, 1984

Filed:

Aug 25, 1983

Appl. No.:

6/526303

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

B01J 4104

US Classification:

210670

Abstract:

Resins bearing picolylamine moieties selectively adsorb iodide ions from acidic aqueous solutions. The iodide can be readily eluted from the resin with base. Particularly useful resins are obtained by reacting chloromethylated styrene-divinylbenzene copolymers with N-(2-hydroxyethyl)-2-picolylamine or bis-(2-picolyl)amine.

US Patent:

47786647, Oct 18, 1988

Filed:

Feb 18, 1987

Appl. No.:

7/015905

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

C01B 2100
C01B 1700
B01J 800

US Classification:

423235

Abstract:

The present invention relates to a cyclic continuous process and composition for the removal of NO and SO. sub. 2 from a variety of fluid streams. A fluid stream containing NO and SO. sub. 2 is contacted with an aqueous solution of water-soluble organic polymeric chelate containing a polyvalent metal, e. g. , Fe (II). The NO is catalytically absorbed and in the presence of SO. sub. 2, the imidodisulfonate is formed. Optionally, a reducing agent, such as sodium hydrogen sulfide, is added to maintain the polyvalent metal in the reduced state. The process next includes removal of the imidodisulfonate formed. The separation of water and low molecular weight materials and products, e. g. molecular weight below 500, usually occurs by ultrafiltration or dialysis, with recycle and re-use of the polyvalent metal chelate.

US Patent:

40988678, Jul 4, 1978

Filed:

Mar 25, 1977

Appl. No.:

5/781100

Inventors:

Robert R. Grinstead - Walnut Creek CA
Wilmonte A. Nasutavicus - Lafayette CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

B01D 1504
B01J 104

US Classification:

423 24

Abstract:

New chelate exchange resins capable of selective recovery of copper, nickel, and other valuable metals from an acidic aqueous leach liquor are prepared by reacting a crosslinked haloalkyl polymer matrix resin (I) with certain aminopyridines (II) to give a resin (III) ##STR1## with pendent methyleneaminopyridine groups attached to the matrix resin. Particularly useful resins are obtained by reacting chloromethylated styrene-divinylbenzene copolymer beads with an aminomethylpyridine, such as 2-picolylamine, N-methyl-2-picolylamine, N-(2-hydroxyethyl)-2-picolylamine, N-(2-methylaminoethyl)-2-picolylamine, or bis-(2-picolyl)amine. At a typical copper ore leach liquor pH of about 2, the picolylamine resins will absorb 15-30 mg copper/ml resin with a 5-10 fold selectivity for copper over ferric iron.

US Patent:

49100025, Mar 20, 1990

Filed:

May 8, 1989

Appl. No.:

7/348629

Inventors:

Robert R. Grinstead - Walnut Creek CA

Assignee:

The Dow Chemical Company - Midland MI

International Classification:

C01B 2100
C01B 1700

US Classification:

423235

Abstract:

The invention relates to a cyclic process for the removal of NO. sub. x and SO. sub. x from a gas stream containing NO. sub. x and SO. sub. x. The gas stream is scrubbed with an aqueous reaction solution containing an organic, water-soluble, polymeric chelate containing a polyvalent metal ion. The NO. sub. x is absorbed and in the presence of SO. sub. x, the imidodisulfonate is formed. The aqueous reaction solution containing chelate and imidodisulfonate is contacted with a first membrane separation means, wherein calcium oxide is added to the first permeate stream, resulting in the precipitation of calcium sulfite. The calcium sulfite is filtered from the first permeate stream, the first permeate stream combined with the first non-permeate stream, and the combined stream contacted with a second membrane separation means which removes a portion of the water and other low molecular weight materials, with recycle of the remaining non-permeate stream containing chelate to the scrubber. Water-soluble alkali is added to the process as needed.