US3635677A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glycol detection in oil
Assignee: Citgo Petroleum Corp
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Filing: 1970-04-30
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Granted: 1972-01-18
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Expires: 1990-04-30
Abstract
Abstract A sample of engine oil is taken from a crankcase and introduced into an aqueous oxidizing solution. The mixture is shaken and allowed to separate into the oil and aqueous phases. A sample of the aqueous phase is then introduced onto a chromogenic aldehyde reagent adsorbed on a suitable supporting media. The sample and reagent are contacted and the presence or absence of glycol in the engine oil is observed by chromogenic determination. The method allows the observation of as little as several parts per million of glycol in oil.
Inventors
- 👤 Harry N Drake Jr
- 👤 Leo A Fabbro
- 👤 Ronald E Fanucci
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:46
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; G01N33/00; G01N33/26; G01N33/28; G01N33/2888; Y; Y10; Y10T; Y10T436/00; Y10T436/20; Y10T436/203332; Y10T436/25; Y10T436/25375; Y10T436/255
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
11 words
The method of claim 1 in which the oil is acidic.
Claim 2
Dependent Claim
16 words
The method of claim 2 in which the chromogenic aldehyde reagent is 3-methyl-2-benzothiazolinone hydrazone hydrOchloride monohydrate.
Claim 3
Dependent Claim
32 words
The method of claim 3 in which a. the oxidizer is selected from the group consisting of sodium periodate, potassium periodate, hydrogen peroxide, sodium perborate, ceric nitrate, ceric sulfate; and lead tetra-acetate.
Claim 4
Dependent Claim
29 words
The method of claim 4 in which the aldehyde reagent support media is selected from the group consisting of silica gel, anhydrous alumina, diatomaceous earth, firebrick and polymeric material.
Claim 5
Dependent Claim
47 words
The method of claim 4 in which: a. the oxidizer is about a 0.01 to 1.0 molar aqueous solution of sodium periodate; b. the aldehyde reagent support media is particulate polyethylene; and c. the chromogenic aldehyde reagent is prepared by adsorbing 3-methyl-2-benzothiazolinone hydrazone hydrochloride monohydrate on polyethylene.
Claim 6
Dependent Claim
51 words
The process of claim 6 in which: a. the oil sample and aqueous phase are mixed for about 1 to about 2 minutes; b. the aqueous phase and chromogenic aldehyde reagent are mixed for about 5 to about 10 seconds; and c. the color is allowed to develop for 15 minutes.
Claim 7
Dependent Claim
12 words
The process of claim 7 in which the glycol is ethylene glycol.
Claim 8
Dependent Claim
23 words
The process of claim 7 whereby the detection takes place in a syringe which contains the chromogenic aldehyde reagent MBTH on particulate polyethylene.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |