Patent US4430240A successfully refreshed from Google Patents.
US4430240A
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De-icing chemicals and their preparation from polysaccharide sources
Assignee: STATE OF SOUTH DAKOTA AS REPRESENTED BY DEPARTMENT OF TRANSPORATION
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Filing: 1982-01-12
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Granted: 1984-02-07
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Expires: 2002-01-12
Abstract
Abstract De-icing chemicals intended primarily for de-icing pavement such as roads,ridges, and runways are prepared from polysaccharide sources (e.g. waste products such as sawdust) by reaction at elevated pressure and temperature with alkaline earth metal oxides or hydroxides in the presence of water. The de-icing chemicals are impure mixtures of alkaline earth metal salts of acetic acid, lactic acid and glycolic acid with the mixture being substantially free of alkaline earth metal salts of oxalic acid and formic acid. The de-icing chemicals are intended to be a substitute for the inorganic chloride salts (e.g. sodium chloride) commonly used for de-icing highways.
Inventors
- 👤 Robert L. Sandvig
- 👤 William A. Klemm
- 👤 Jack R. Gaines
- 👤 Robert W. Looyenga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:26
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/18; C09K3/185
Claims Analysis
Total Claims: 52
Claim 1
Independent Claim
51 words
The method of de-icing which comprises contacting an iced surface with a de-icing chemical, said chemical consisting essentially of a mixture of alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid with the mixture being substantially free of alkaline earth metal salts of oxalic acid or formic acid.
Claim 2
Independent Claim
51 words
The method of de-icing which comprises contacting an iced surface with a de-icing chemical, said chemical consisting essentially of a mixture of alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid with the mixture being substantially free of alkaline earth metal salts of oxalic acid or formic acid.
Claim 3
Dependent Claim
13 words
Methods of claim 1 in which the de-icing chemical is a particulate solid.
Claim 4
Dependent Claim
12 words
Methods of claim 1 in which the de-icing chemical is a liquid.
Claim 5
Dependent Claim
12 words
Methods of claim 3 in which the alkaline earth metal is calcium.
Claim 6
Dependent Claim
44 words
A mixture of chemicals useful as a de-icing chemical, said mixture consisting essentially of the alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid with the mixture being substantially free of alkaline earth metal salts of oxalic acid or formic acid.
Claim 7
Dependent Claim
44 words
A mixture of chemicals useful as a de-icing chemical, said mixture consisting essentially of the alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid with the mixture being substantially free of alkaline earth metal salts of oxalic acid or formic acid.
Claim 8
Dependent Claim
15 words
Mixtures of chemicals according to claim 5 in which the alkaline earth metal is calcium.
Claim 9
Dependent Claim
101 words
The process of producing a mixture of chemicals which is useful as a de-icer, said process comprising the following steps: (a) reacting a polysaccharide raw material with a treating agent selected from the group consisting of alkaline earth metal oxides and hydroxides; said reaction occuring under aqueous conditions and at superatmospheric pressure; thereby producing a crude reaction product; (b) separating and recovering from said reaction product a mixture of chemicals that contains alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid; said mixture being substantially free of the alkaline earth metal salts of formic acid and oxalic acid.
Claim 10
Dependent Claim
101 words
The process of producing a mixture of chemicals which is useful as a de-icer, said process comprising the following steps: (a) reacting a polysaccharide raw material with a treating agent selected from the group consisting of alkaline earth metal oxides and hydroxides; said reaction occuring under aqueous conditions and at superatmospheric pressure; thereby producing a crude reaction product; (b) separating and recovering from said reaction product a mixture of chemicals that contains alkaline earth metal salts of acetic acid, lactic acid, and glycolic acid; said mixture being substantially free of the alkaline earth metal salts of formic acid and oxalic acid.
Claim 11
Dependent Claim
16 words
The process of claim 7 in which the source of polysaccharide is a solid, cellulosic material.
Claim 12
Dependent Claim
14 words
The process of claim 7 in which the source of polysaccharide is wood particles.
Claim 13
Dependent Claim
14 words
The process of claim 7 in which the source of polysaccharide is waste paper.
Claim 14
Dependent Claim
13 words
The process of claim 9 in which the alkaline earth metal is calcium.
Claim 15
Dependent Claim
13 words
The process of claim 11 in which the alkaline earth metal is magnesium.
Claim 16
Dependent Claim
41 words
The process of claim 12 in which the reaction product is cooled from a reaction temperature to a temperature below 150° C. by releasing the pressure on the rection system to cause flash evaporation of volatile components of the reaction mixture.
Claim 17
Dependent Claim
158 words
The process of producing a mixture of chemicals which is useful as a de-icer, said process comprising the following steps: (a) pre-soaking a cellulosic raw material in water for at least four hours; (b) mixing the wet cellulosic material with a treating agent selected from the group consisting of alkaline earth metal oxides and hydroxides; (c) heating the wet mixture in a closed system to a reaction temperature; (d) reacting the wet mixture to form a reaction mixture; (e) reducing the temperature of the reaction mixture; (f) removing volatile by-products of the reaction from the reaction mixture; (g) separating the reaction mixture into a liquid phase and a solid phase; (h) recovering from the liquid phase a mixture of chemicals, said mixture being characterized by the presence of alkaline earth salts of acetic acid, lactic acid and glycolic acid and being further characterized by the substantial absence of the alkaline earth salts of oxalic acid and formic acid.
Claim 18
Dependent Claim
158 words
The process of producing a mixture of chemicals which is useful as a de-icer, said process comprising the following steps: (a) pre-soaking a cellulosic raw material in water for at least four hours; (b) mixing the wet cellulosic material with a treating agent selected from the group consisting of alkaline earth metal oxides and hydroxides; (c) heating the wet mixture in a closed system to a reaction temperature; (d) reacting the wet mixture to form a reaction mixture; (e) reducing the temperature of the reaction mixture; (f) removing volatile by-products of the reaction from the reaction mixture; (g) separating the reaction mixture into a liquid phase and a solid phase; (h) recovering from the liquid phase a mixture of chemicals, said mixture being characterized by the presence of alkaline earth salts of acetic acid, lactic acid and glycolic acid and being further characterized by the substantial absence of the alkaline earth salts of oxalic acid and formic acid.
Claim 19
Dependent Claim
17 words
The process of claim 14 in which the source of cellulose is a solid, cellulosic waste product.
Claim 20
Dependent Claim
14 words
The process of claim 14 in which the source of cellulose is wood particles.
Claim 21
Dependent Claim
14 words
The process of claim 14 in which the source of cellulose is waste paper.
Claim 22
Dependent Claim
13 words
The process of claim 16 in which the alkaline earth metal is calcium.
Claim 23
Dependent Claim
25 words
The process of claim 18 in which the amount of water present is sufficient to provide a solids content of 5 to 50 weight percent.
Claim 24
Dependent Claim
44 words
The process of claim 19 in which the reaction product is cooled from a reaction temperature above 150° C. to a temperature below 150° C. by releasing the pressure on the reaction system to cause flash evaporation of volatile components of the reaction mixture.
Claim 25
Dependent Claim
8 words
Product produced by the process of claim 7.
Claim 26
Dependent Claim
8 words
Product produced by the process of claim 8.
Claim 27
Dependent Claim
8 words
Product produced by the process of claim 9.
Claim 28
Dependent Claim
8 words
Product produced by the process of claim 10.
Claim 29
Dependent Claim
8 words
Product produced by the process of claim 11.
Claim 30
Dependent Claim
8 words
Product produced by the process of claim 12.
Claim 31
Dependent Claim
8 words
Product produced by the process of claim 13.
Claim 32
Dependent Claim
8 words
Product produced by the process of claim 14.
Claim 33
Dependent Claim
8 words
Product produced by the process of claim 15.
Claim 34
Dependent Claim
8 words
Product produced by the process of claim 16.
Claim 35
Dependent Claim
8 words
Product produced by the process of claim 17.
Claim 36
Dependent Claim
8 words
Product produced by the process of claim 18.
Claim 37
Dependent Claim
8 words
Product produced by the process of claim 19.
Claim 38
Dependent Claim
8 words
Product produced by the process of claim 20.
Claim 39
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 21.
Claim 40
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 22.
Claim 41
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 23.
Claim 42
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 24.
Claim 43
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 25.
Claim 44
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 26.
Claim 45
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 27.
Claim 46
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 28.
Claim 47
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 29.
Claim 48
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 30.
Claim 49
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 31.
Claim 50
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 32.
Claim 51
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 33.
Claim 52
Dependent Claim
15 words
The method of de-icing which comprises contacting an iced surface with product of claim 34.
References Cited (Backward Citations)
US4351669A
Cited
US4377488A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-06 | 1987-08-08 | 1988-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-06 | 1991-08-08 | 1992-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-06 | 1995-08-08 | 1996-02-07 | $7700.00 | Window Closed / Lapsed |