Patent US5376293A successfully refreshed from Google Patents.
US5376293A
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Deicer
Assignee: South Dakota Department of Transportation
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Filing: 1993-09-09
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Granted: 1994-12-27
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Expires: 2013-09-09
Abstract
Abstract Improved deicer compositions containing crystalline double salts formed from mixtures of relatively low molecular weight carboxylic acids (for example, mixtures of formic acid and acetic acid) are provided. The deicer compositions are generally prepared by neutralizing an aqueous mixture containing at least two carboxylic acids or salts thereof, adjusting the pH to between about 7 and about 10, and drying the aqueous mixture to obtain a double salt crystalline product. Double salts containing sodium cations and double salts containing sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium provide effective deicing compositions which are environmentally safer than conventional deicing compositions.
Inventors
- 👤 Daniel P. Johnston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:26
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/18; C09K3/185
Claims Analysis
Total Claims: 54
Claim 1
Independent Claim
190 words
A deicing composition comprising a crystalline double salt formed by (1) neutralizing an aqueous mixture of at least two organic carboxylic acids containing from 1 to 3 carbon atoms or salts thereof with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the aqueous mixture of at least two carboxylic acids contains formic acid and acetic acid, or salts thereof, such that the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 2
Dependent Claim
190 words
A deicing composition comprising a crystalline double salt formed by (1) neutralizing an aqueous mixture of at least two organic carboxylic acids containing from 1 to 3 carbon atoms or salts thereof with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the aqueous mixture of at least two carboxylic acids contains formic acid and acetic acid, or salts thereof, such that the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 3
Dependent Claim
64 words
A deicing composition as defined in claim 1, wherein the aqueous mixture of at least two carboxylic acids contains an additional organic carboxylic acid selected from the group consisting of glycolic acid, lactic acid, salts thereof, and mixtures thereof and wherein the deicing composition has ice penetration capacity at least equivalent to sodium chloride and an eutectic temperature of less than about -20° C.
Claim 4
Dependent Claim
26 words
A deicing composition as defined in claim 1, wherein the neutralization agent is selected from the group consisting of sodium carbonate, sodium hydroxide, and mixtures thereof.
Claim 5
Dependent Claim
38 words
A deicing composition as defined in claim 3, wherein the neutralization agent further contains at least one additional material selected from the group consisting of potassium hydroxide, potassium carbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, and calcium hydroxide.
Claim 6
Dependent Claim
30 words
A deicing composition am defined in claim 3, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 7
Dependent Claim
30 words
A deicing composition as defined in claim 4, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 8
Dependent Claim
24 words
A deicing composition as defined in claim 5, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 9
Dependent Claim
24 words
A deicing composition as defined in claim 6, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 10
Dependent Claim
21 words
A deicing composition as defined in claim 1, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 11
Dependent Claim
21 words
A deicing composition as defined in claim 5, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 12
Dependent Claim
21 words
A deicing composition as defined in claim 6, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 13
Independent Claim
192 words
A method for deicing ice- or snow-covered structures, said method comprising applying an effective amount of a deicing composition to the structure to be deiced, wherein the deicing composition comprises a crystalline double salt formed by (1) neutralizing an aqueous mixture containing acetic acid and formic acid, or salts thereof, with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the molar ratio of acetic acid to formic acid, or salts thereof, in the aqueous mixture is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 14
Independent Claim
192 words
A method for deicing ice- or snow-covered structures, said method comprising applying an effective amount of a deicing composition to the structure to be deiced, wherein the deicing composition comprises a crystalline double salt formed by (1) neutralizing an aqueous mixture containing acetic acid and formic acid, or salts thereof, with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the molar ratio of acetic acid to formic acid, or salts thereof, in the aqueous mixture is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 15
Dependent Claim
49 words
A deicing method as defined in claim 12, wherein the deicing composition has ice penetration capacity at least equivalent to sodium chloride and an eutectic temperature of less than about -20° C., and wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 16
Dependent Claim
26 words
A deicing method as defined in claim 13, wherein the neutralization agent is selected from the group consisting of sodium carbonate, sodium hydroxide, and mixtures thereof.
Claim 17
Dependent Claim
38 words
A deicing method as defined in claim 14, wherein the neutralization agent further contains at least one additional material selected from the group consisting of potassium hydroxide, potassium carbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, and calcium hydroxide.
Claim 18
Dependent Claim
30 words
A deicing method as defined in claim 14, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 19
Dependent Claim
30 words
A deicing method as defined in claim 15, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 20
Dependent Claim
24 words
A deicing method as defined in claim 16, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 21
Dependent Claim
24 words
A deicing method as defined in claim 17, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 22
Dependent Claim
21 words
A deicing method as defined in claim 16, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 23
Dependent Claim
21 words
A deicing method as defined in claim 17, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 24
Dependent Claim
23 words
A deicing composition comprising a crystalline sodium double salt of general formula Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-).n(H.sub.2 O), where n equals 0 to 5.
Claim 25
Dependent Claim
23 words
A deicing composition comprising a crystalline sodium double salt of general formula Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-).n(H.sub.2 O), where n equals 0 to 5.
Claim 26
Dependent Claim
24 words
A deicing composition as defined in claim 22, wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 27
Dependent Claim
24 words
A deicing composition as defined in claim 23, wherein the average particle size of the crystalline double salt is about 2 to 9 mm.
Claim 28
Independent Claim
235 words
A method for treating structures selected from the group consisting of highways, bridges, and sidewalks whereby the strength of the bond between the surface of the structure and later accumulated ice or snow on the surface is reduced, said method comprising applying an effective anti-icing amount of a composition to the surface of the structure to be treated, wherein the composition comprises a crystalline double salt or an aqueous solution thereof, wherein the crystalline double salt is formed by (1) neutralizing an aqueous mixture containing formic acid and acetic acid, or salts thereof, with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the molar ratio of acetic acid to formic acid, or salts thereof, in the aqueous mixture is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 29
Independent Claim
235 words
A method for treating structures selected from the group consisting of highways, bridges, and sidewalks whereby the strength of the bond between the surface of the structure and later accumulated ice or snow on the surface is reduced, said method comprising applying an effective anti-icing amount of a composition to the surface of the structure to be treated, wherein the composition comprises a crystalline double salt or an aqueous solution thereof, wherein the crystalline double salt is formed by (1) neutralizing an aqueous mixture containing formic acid and acetic acid, or salts thereof, with a neutralizing agent, wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, (2) adjusting the pH of the neutralized aqueous mixture to about 7 to 10 with a pH adjusting agent, wherein said pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the crystalline double salt, wherein the molar ratio of acetic acid to formic acid, or salts thereof, in the aqueous mixture is in the range of about 1:4 to 4:1 and wherein said double salt contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium.
Claim 30
Dependent Claim
48 words
A method as defined in claim 25, wherein the deicing composition has ice penetration capacity at least equivalent to sodium chloride and an eutectic temperature of less than about -20° C., and wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 31
Dependent Claim
25 words
A method as defined in claim 26, wherein the neutralization agent is selected from the group consisting of sodium carbonate, sodium hydroxide, and mixtures thereof.
Claim 32
Dependent Claim
37 words
A method as defined in claim 27, wherein the neutralization agent further contains at least one additional material selected from the group consisting of potassium hydroxide, potassium carbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, and calcium hydroxide.
Claim 33
Dependent Claim
29 words
A method as defined in claim 27, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 34
Dependent Claim
29 words
A method as defined in claim 28, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 35
Dependent Claim
23 words
A method as defined in claim 29, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 36
Dependent Claim
23 words
A method as defined in claim 30, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is about 1:1.
Claim 37
Dependent Claim
20 words
A method as defined in claim 29, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 38
Dependent Claim
20 words
A method as defined in claim 30, wherein the pH of the neutralized aqueous mixture is adjusted to about 9.
Claim 39
Dependent Claim
25 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)K.sup.+ (HCOO.sup.-)K.sup.+ (CH.sub.3 COO.sup.-).n(H.sub.2 O), where n equals 0 to 5.
Claim 40
Dependent Claim
25 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)K.sup.+ (HCOO.sup.-)K.sup.+ (CH.sub.3 COO.sup.-).n(H.sub.2 O), where n equals 0 to 5.
Claim 41
Dependent Claim
24 words
A deicing composition as defined in claim 35, wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 42
Dependent Claim
26 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)Ca.sup.+2 (HCOO.sup.-).sub.2 Ca.sup.+2 (CH.sub.3 COO.sup.-).sub.2.n(H.sub.2 O), where n equals 0 to 5.
Claim 43
Dependent Claim
26 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)Ca.sup.+2 (HCOO.sup.-).sub.2 Ca.sup.+2 (CH.sub.3 COO.sup.-).sub.2.n(H.sub.2 O), where n equals 0 to 5.
Claim 44
Dependent Claim
24 words
A deicing composition as defined in claim 37, wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 45
Dependent Claim
26 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)Mg.sup.+2 (HCOO.sup.-).sub.2 Mg.sup.+2 (CH.sub.3 COO.sup.-).sub.2.n(H.sub.2 O), where n equals 0 to 5.
Claim 46
Dependent Claim
26 words
A deicing composition comprising a crystalline double salt of general formula: Na.sup.+ (HCOO.sup.-)Na.sup.+ (CH.sub.3 COO.sup.-)Mg.sup.+2 (HCOO.sup.-).sub.2 Mg.sup.+2 (CH.sub.3 COO.sup.-).sub.2.n(H.sub.2 O), where n equals 0 to 5.
Claim 47
Dependent Claim
24 words
A deicing composition as defined in claim 39, wherein the average particle size of the crystalline double salt is about 1 to 12.5 mm.
Claim 48
Dependent Claim
130 words
A deicing composition formed by (1) neutralizing with a neutralization agent wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, an aqueous mixture containing formic acid and acetic acid, or salts thereof, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:4 to 4:1, (2) adjusting the pH of the neutralized aqueous mixture no about 7 to 10 with a pH adjusting agent, wherein the pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the deicing composition.
Claim 49
Dependent Claim
130 words
A deicing composition formed by (1) neutralizing with a neutralization agent wherein said neutralizing agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium and magnesium, an aqueous mixture containing formic acid and acetic acid, or salts thereof, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:4 to 4:1, (2) adjusting the pH of the neutralized aqueous mixture no about 7 to 10 with a pH adjusting agent, wherein the pH adjusting agent contains sodium cations or sodium cations and at least one cation selected from the group consisting of potassium, calcium, and magnesium, and (3) removing the water from the pH-adjusted aqueous mixture to obtain the deicing composition.
Claim 50
Dependent Claim
64 words
A deicing composition as defined in claim 41, wherein the aqueous mixture containing formic acid and acetic acid contains an additional organic carboxylic acid selected from the group consisting of glycolic acid, lactic acid, salts thereof, and mixtures thereof and wherein the deicing composition has ice penetration capacity at least equivalent to sodium chloride and an eutectic temperature of less than about -20° C.
Claim 51
Dependent Claim
26 words
A deicing composition as defined in claim 41, wherein the neutralization agent is selected from the group consisting of sodium carbonate, sodium hydroxide, and mixtures thereof.
Claim 52
Dependent Claim
38 words
A deicing composition as defined in claim 43, wherein the neutralization agent further contains at least one additional material selected from the group consisting of potassium hydroxide, potassium carbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, and calcium hydroxide.
Claim 53
Dependent Claim
30 words
A deicing composition as defined in claim 43, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
Claim 54
Dependent Claim
30 words
A deicing composition as defined in claim 44, wherein the molar ratio of acetic acid to formic acid, or salts thereof, is in the range of about 1:2 to 2:1.
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