US4251218A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of adjusting pH
Assignee: Bank of America Illinois
•
Filing: 1978-08-07
•
Granted: 1981-02-17
•
Expires: 1998-08-07
Abstract
Abstract In a potentiometric system for measuring low levels of ion activity, a method of adjusting the pH in a sample stream by the passive addition of low molecular weight acid or base reagent, without dilution of the sample stream, and without introduction of any interfering, reactive or test ions into the sample stream. A membrane is provided, permeable to the acid or base reagent used to adjust sample stream pH, and impermeable to ionic species. The membrane is placed between a reagent reservoir and the sample stream. Constant flow of the sample stream by the membrane maintains the reagent partial pressure differential between the reservoir and the stream, causing diffusion of reagent through the membrane into said stream.
Inventors
- 👤 Albert A. Diggens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:17
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/40; Y; Y10; Y10T; Y10T436/00; Y10T436/25
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
108 words
A method of raising the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight base reagent; and diffusing a low molecular weight base reagent through the membrane and into the stream by contacting the other side of said membrane with said base reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 2
Independent Claim
108 words
A method of raising the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight base reagent; and diffusing a low molecular weight base reagent through the membrane and into the stream by contacting the other side of said membrane with said base reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein the base reagent is ammonia.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein the base reagent is piperidine.
Claim 5
Dependent Claim
11 words
The method of claim 1 wherein the base reagent is dimethylamine.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein the membrane is composed of silicone rubber.
Claim 7
Dependent Claim
15 words
The method of claim 1 wherein the membrane is composed of silicone rubber polycarbonate copolymer.
Claim 8
Dependent Claim
13 words
The method of claim 1 wherein the membrane is composed of microporous teflon.
Claim 9
Dependent Claim
13 words
The method of claim 1 wherein the membrane is composed of microporous polypropylene.
Claim 10
Independent Claim
118 words
A method of raising the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight base reagent; and diffusing a low molecular weight base reagent selected from the group consisting of ammonia, piperidine and dimethylamine, through the membrane and into the stream by contacting the other side of said membrane with said base reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 11
Independent Claim
118 words
A method of raising the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight base reagent; and diffusing a low molecular weight base reagent selected from the group consisting of ammonia, piperidine and dimethylamine, through the membrane and into the stream by contacting the other side of said membrane with said base reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 12
Independent Claim
109 words
A method of lowering the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is p permeable to a low molecular weight acid reagent; and diffusing a low molecular weight acid reagent through the membrane and into the stream by contacting the other side of said membrane with said acid reagent, whereby the pH of the stream is lowered without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 13
Independent Claim
109 words
A method of lowering the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is p permeable to a low molecular weight acid reagent; and diffusing a low molecular weight acid reagent through the membrane and into the stream by contacting the other side of said membrane with said acid reagent, whereby the pH of the stream is lowered without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 14
Dependent Claim
12 words
The method of claim 10 wherein the acid reagent is acetic acid.
Claim 15
Dependent Claim
12 words
The method of claim 10 wherein the acid reagent is proprionic acid.
Claim 16
Dependent Claim
12 words
The method of claim 10 wherein the acid reagent is hydrochloric acid.
Claim 17
Dependent Claim
13 words
The method of claim 10 wherein the acid reagent is hydrogen iodide, HI.
Claim 18
Dependent Claim
17 words
The method of claim 10 wherein the acid reagent is formic acid, CH 2 O 2 .
Claim 19
Dependent Claim
13 words
The method of claim 10 wherein the membrane is composed of silicone rubber.
Claim 20
Dependent Claim
14 words
The method of claim 10 wherein the membrane is composed of silicone polycarbonate copolymer.
Claim 21
Dependent Claim
13 words
The method of claim 10 wherein the membrane is composed of microporous teflon.
Claim 22
Dependent Claim
13 words
The method of claim 10 wherein the membrane is composed of microporous polypropylene.
Claim 23
Independent Claim
125 words
A method of lowering the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight acid reagent; and diffusing a low molecular weight acid reagent selected from the group consisting of acetic acid, proprionic acid, hydrochloric acid, hydrogen, iodide, and formic acid, through the membrane and into the stream by contacting the other side of said membrane with said acid reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
Claim 24
Independent Claim
125 words
A method of lowering the pH of a sample stream without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream, comprising: continuously passing a sample stream over one side of an inert ion-impermeable non-wetting membrane that is permeable to a low molecular weight acid reagent; and diffusing a low molecular weight acid reagent selected from the group consisting of acetic acid, proprionic acid, hydrochloric acid, hydrogen, iodide, and formic acid, through the membrane and into the stream by contacting the other side of said membrane with said acid reagent, whereby the pH of the stream is raised without dilution of the sample stream and without introducing any interfering, reactive, or test ions into the sample stream.
References Cited (Backward Citations)
US3367850A
Cited
US3495943A
Cited
US3545931A
Cited
US3689222A
Cited
US3864087A
Cited
US3935096A
Cited
US3996123A
Cited
US3923461A
Cited
US4025308A
Cited
US4131428A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |