Jian S Qi

US Patent:

53368061, Aug 9, 1994

Filed:

Sep 20, 1993

Appl. No.:

8/122947

Inventors:

Jian S. Qi - Amherst NY

Assignee:

Occidental Chemical Corporation - Niagara Falls NY

International Classification:

C07C 5146
C07C 5143
C07C 5142

US Classification:

562494

Abstract:

Disclosed is a process for isolating and purifying 2,4,5-trifluorobenzoic acid from a solution in a decarboxylating solvent such as NMP. The solution is neutralized with a hydroxide. This results in the formation of a salt of the 2,4,5-trifluorobenzoic acid, which precipitates. The slurry is filtered to collect the precipitated salt and the precipitated salt is dissolved in water. The aqueous solution of the salt is then acidified which results in the reformation and precipitation of the 2,4,5-trifluorobenzoic acid.

US Patent:

56610378, Aug 26, 1997

Filed:

Jun 10, 1996

Appl. No.:

8/660993

Inventors:

Jian Steven Qi - Buffalo NY
David E. Albright - Niagara Falls NY
Garra C. Lester - Eden NY

International Classification:

G01N 2164

US Classification:

436128

Abstract:

Disclosed is a method of determining whether a solvent contains a tautomeric cyclic 1,2-dione. It is first determined whether the pH of the solvent is acidic (9), or neutral (5 to 9). If the pH is neutral, an acid or a base is added to make the pH acidic or basic, respectively. The UV absorbance at a first wavelength between about 230 nm and about 270 nm and at a second wavelength between about 280 and about 320 nm is determined. If the pH is acid, it is changed to basic and, if it is basic, it is changed to acidic. The UV absorbance at the first and second wavelengths is again determined. The presence of a tautomeric cyclic 1,2-dione is indicated if the absorbance at the first wavelength was greater when the solvent was acidic and the absorbance at the second wavelength was greater when the solvent was basic. The concentration of the tautomeric cyclic 1,2-dione can be determined by multiplying the change in absorbance by a constant.

US Patent:

53712790, Dec 6, 1994

Filed:

Mar 21, 1994

Appl. No.:

8/210853

Inventors:

Jian S. Qi - Amherst NY
Garra C. Lester - Eden NY

Assignee:

Occidental Chemical Corporation - Niagara Falls NY

International Classification:

C07C 6702

US Classification:

560263

Abstract:

Disclosed is a method of making a liquid ether acetate. After reacting acetic acid with the corresponding ether alcohol, the resulting mixture of ether acetate, water, acetic acid, and ether alcohol is, with no distillation, contacted with alumina. Particular ether acetates that can be treated include ethylene glycol monobutyl ether acetate and diethylene glycol monobutyl ether acetate. The treated acetates are more stable to hydrolysis after they have been passed over a bed of alumina.

US Patent:

56590733, Aug 19, 1997

Filed:

Jul 7, 1995

Appl. No.:

8/499459

Inventors:

Jian Steven Qi - Amherst NY

International Classification:

C07C 6724

US Classification:

560240

Abstract:

Disclosed is a method of making a glycol ether acetate. Acetic acid is reacted with a glycol ether at a molar ratio of about 1. 1 to about 2, in a mixture with a catalyst and an azeotropic agent which can be either butyl acetate or dibutyl ether. The mixture is heated to a temperature and pressure sufficient to vaporize an azeotrope of water and the azeotropic agent. In another embodiment of the invention, a glycol ether acetate is made by preparing a reaction mixture of acetic acid and a glycol ether in a molar ratio of about 1. 1 to about 1. 2, about 5 to about 25 wt % n-butanol, an additional amount of acetic acid stoichiometric with the amount of n-butanol, and a catalyst. The reaction mixture is heated to form a glycol ether acetate, water, and butyl acetate. The azeotrope, excess acetic acid, butyl acetate, and glycol ether are successively removed by distillation.

US Patent:

56273290, May 6, 1997

Filed:

Sep 13, 1995

Appl. No.:

8/527609

Inventors:

Chandrasekhar Krishnan - Grand Island NY
Jian S. Qi - Amherst NY
Joseph A. Incavo - Snyder NY
William L. Reuter - Niagara Falls NY
Vivek Jain - Grand Island NY

Assignee:

Occidental Chemical Corporation - Niagara Falls NY

International Classification:

G01N 1500
G01N 1300

US Classification:

73866

Abstract:

Disclosed is a method of determining a diffusion coefficient for a diffusant in a particulate. An inert gas is passed through a particulate containing the diffusant. A parameter that is proportional to the concentration of the diffusant in the inert gas is measured over a period of time and the slope of the linear portion of that relationship is determined and is multiplied by a constant.