US2971813A - Treatment of montan wax with chromic acid and simultaneous formation of chromic tanning mash - Google Patents
Treatment of montan wax with chromic acid and simultaneous formation of chromic tanning mash Download PDFInfo
- Publication number
- US2971813A US2971813A US688140A US68814057A US2971813A US 2971813 A US2971813 A US 2971813A US 688140 A US688140 A US 688140A US 68814057 A US68814057 A US 68814057A US 2971813 A US2971813 A US 2971813A
- Authority
- US
- United States
- Prior art keywords
- montan wax
- mash
- wax
- chromic
- tanning
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 title claims description 13
- 239000012170 montan wax Substances 0.000 title description 37
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 title description 9
- 230000015572 biosynthetic process Effects 0.000 title description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 21
- 229910017604 nitric acid Inorganic materials 0.000 claims description 21
- 239000011541 reaction mixture Substances 0.000 claims description 16
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 7
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 239000007800 oxidant agent Substances 0.000 claims description 6
- 230000000630 rising effect Effects 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 3
- 238000001694 spray drying Methods 0.000 claims description 2
- 239000001993 wax Substances 0.000 description 25
- 235000006085 Vigna mungo var mungo Nutrition 0.000 description 19
- 240000005616 Vigna mungo var. mungo Species 0.000 description 19
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 6
- SOCTUWSJJQCPFX-UHFFFAOYSA-N dichromate(2-) Chemical compound [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O SOCTUWSJJQCPFX-UHFFFAOYSA-N 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- KIEOKOFEPABQKJ-UHFFFAOYSA-N sodium dichromate Chemical compound [Na+].[Na+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KIEOKOFEPABQKJ-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 150000001340 alkali metals Chemical class 0.000 description 2
- 235000014113 dietary fatty acids Nutrition 0.000 description 2
- 239000000194 fatty acid Substances 0.000 description 2
- 229930195729 fatty acid Natural products 0.000 description 2
- 150000004665 fatty acids Chemical class 0.000 description 2
- 239000010985 leather Substances 0.000 description 2
- 229920000136 polysorbate Polymers 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 238000004061 bleaching Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000032050 esterification Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
- C14C3/00—Tanning; Compositions for tanning
- C14C3/02—Chemical tanning
- C14C3/04—Mineral tanning
- C14C3/06—Mineral tanning using chromium compounds
Definitions
- the method leading to most valuable products is that which consists in treating the wax at an elevated temperature with a mixture of sulphuric acid and chromic acid or sodium bichromate or patassium bichromate and -in combining subsequently the fatty acids obtained in the oxidized wax, with, dependently on the desired properties of the final products, alcohols or amines, eventually with the partial conversion of the fatty acids into salts of the alkali metal or earth alkali metal group.
- chromic acid or of bichromates for the oxidation of wax exhibits the great advantage that the oxidized product obtains, without losing the hardness characterizing montan wax, besides the light colour, a high acid number which is of essential importance when further working the wax.
- the disadvantage of this method consists in that a relatively great quantity of compounds of the six valent chrome must be used e.g. to one part of montan wax about 3.5 parts of sodium bichromate are used.
- bituminous substances used, among others, waxes e.g. montan waxes, one part of said bituminous substance passing into the mash, while the remaining part oxidizes to the improved waxes.
- waxes e.g. montan waxes
- This proceeding is described in the Polish Patent No. 33,690 and constitutes a very advantageous solution of a cheap parallel production of improved waxes especially 'for the reason that the obtained mash exhibits better tanning properties than mashes normally prepared in tanneries.
- the quantity of bichromate which is required for a suitable oxidation of the wax is decreased up to about one third, a light-coloured, almost white product of a great hardness and of a high acid number being obtained, said number qualifying the same, after the wax has been submitted to esterification, as a wax of the highest quality.
- the proceeding according to the present invention consists in that disresined or not disresined wax is preliminarily treated with nitric acid of a concentration of 46-50%, at a temperature not exceedng C. and no longer than one hour.
- This preliminary treatment of the wax with nitric acid is most advantageously achieved according to the method of bleaching wax as stated in the Polish.
- Patent No. 39,139 in which the nitric acid is caused to act upon the wax suspended therein, the wax having previously been crumbled so that the reaction revealing itself by the increase of the temperature, takesplace spontaneously without any supply of heat from. without.
- Keeping the temperature without exceeding 80 is obtained according to the invention, by suitably choosing, dependently on the quantity and on thequality of the montan wax, the concentration of the nitric acid within the above mentioned limits of 40-50%.
- the preliminary treatment of the wax with nitric acid . is interrupted latest after an hour by pouring cold water on the mixture. Subsequently the wax is cleansed with water and thereupon it is oxidized by means of bichromate or chromic acid, without having been previously dried, 1 kg. of sodium bichromate being used to 1 kg. of montan wax of the start.
- the montan wax preliminarily treated with nitric acid is oxidized most advantageously as stated in the Polish Patent No. 33,690 according to which, in addition to improved wax, chromic mash for tanning leather is obtained.
- the quantity of the obtained mash is in this case not so great when compared with the quantity of the obtained improved wax.
- a method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about be- 7 tween 10-50%, so as to cause an exothermic reaction be tween said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above about 80 C.; coo ing said reaction mixture so as to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said reaction mixture; and subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
- a method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 40-50%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed 16- action mixture; allowing said mixture to react for a period of about one hour while preventing the tempera- "ture thereof from rising above about 80 C.; thereafter introducing cold water into said reaction mixture so as to cool the same sutficieutly to substantially terminate said reaction; separating the thus treated montan wax fromthe remainder of said reaction mixture; and subjecting said separated montanwax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
- a method for improving montan wax comprising 'the steps of dispersing montan wax in an aqueous soluducing cold water into said reaction mixture so as to cool the same'sufiiciently to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said "reaction mixture; washing said separated montan wax with water so as to remove residual "aqueous nitric acid'therefrom; and subjecting said sepa rated and washed montan wax to the action of an aqueous solution of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
- Amethod for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 40-50%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above 80 C.; cooling said reaction mixture .4 so as to substantia ly terminate said reaction; separating the thus treated montan wax from the remainder ot said reaction mixture; subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates, so as to improve the quality of said montan wax and simultaneously to form a chromic tanningmash; and separating the thus treated'montan wax from said tanning mash.
- a method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 4050%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above about C.; cooling said reaction mixture so as to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said reaction mixture; subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates, so as to improve the quality of said montan wax and simultaneously to form a chromic tanning mash; separating the thus treated montan wax from said tanning mash; and spray drying the thus separated tanning mash so as to transform the same into a powdery dry substance.
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Treatment And Processing Of Natural Fur Or Leather (AREA)
Description
P A 2,971,813 Patented Feb 14, 19.61
TREATMENT OF MONTAN WAX WITH CHROMIC ACID AND SIMULTANEOUS FORMATION OF CHROMIC TANNING MASH Antoni Sentek, Swierczewskiego-street 149, m.104, Warsaw, Poland No Drawing. Filed Oct. 4, 1957, Ser. No. 688,140
Claims priority, application Poland Oct. 16, 1956 5 Claims. (Cl. 8-94.26)
Among the known methods of improving montan wax, the method leading to most valuable products is that which consists in treating the wax at an elevated temperature with a mixture of sulphuric acid and chromic acid or sodium bichromate or patassium bichromate and -in combining subsequently the fatty acids obtained in the oxidized wax, with, dependently on the desired properties of the final products, alcohols or amines, eventually with the partial conversion of the fatty acids into salts of the alkali metal or earth alkali metal group.
The use of chromic acid or of bichromates for the oxidation of wax exhibits the great advantage that the oxidized product obtains, without losing the hardness characterizing montan wax, besides the light colour, a high acid number which is of essential importance when further working the wax.
The disadvantage of this method consists in that a relatively great quantity of compounds of the six valent chrome must be used e.g. to one part of montan wax about 3.5 parts of sodium bichromate are used.
It is true, that according to known methods the waste compounds of the trivalent chrome are in known manners reoxidized to the compounds of the six valent chrome, but such an oxidation is expensive and connected with considerable chrome losses.
The method of obtaining a chrome mash for tanning to leather, in which for reducing the six valent chrome compounds and for introducing the required substances into the mash, bituminous substances are used, is also known. When applying this method, as bituminous substances are used, among others, waxes e.g. montan waxes, one part of said bituminous substance passing into the mash, while the remaining part oxidizes to the improved waxes. This proceeding is described in the Polish Patent No. 33,690 and constitutes a very advantageous solution of a cheap parallel production of improved waxes especially 'for the reason that the obtained mash exhibits better tanning properties than mashes normally prepared in tanneries. The demand for improved waxes being very brisk, the quantities of the obtained mash may, however, be, for contrivance reasons, too considerable and burdensome to the wax-producer, whereby the problem of reducing the proportional quantity of tanning mash and the use of bichromate remained actual also in this case.
Trials have been made for solving this problem by preliminarily treating the wax with nitric acid, the results were however unsatisfactory. On treating the wax with nitric acid having a concentration of above 30,% and oxidizing the same subsequently with a dim nished quantity of bichromate, soft and mucilaginous products were obtained.
On treating preliminarily disresined wax with nitric acid having a concentration of below 30%, after its subsequent oxidation by means of a diminished quantity of bichromate, light-coloured and hard wax was obtained, but the time of the preliminary treatment of the wax with nitric acid was too long and took 6-10 hours at a temperature of 95-100 C.
In the proceeding according to the present invention, the quantity of bichromate which is required for a suitable oxidation of the wax, is decreased up to about one third, a light-coloured, almost white product of a great hardness and of a high acid number being obtained, said number qualifying the same, after the wax has been submitted to esterification, as a wax of the highest quality.
The proceeding according to the present invention consists in that disresined or not disresined wax is preliminarily treated with nitric acid of a concentration of 46-50%, at a temperature not exceedng C. and no longer than one hour. This preliminary treatment of the wax with nitric acid is most advantageously achieved according to the method of bleaching wax as stated in the Polish. Patent No. 39,139, in which the nitric acid is caused to act upon the wax suspended therein, the wax having previously been crumbled so that the reaction revealing itself by the increase of the temperature, takesplace spontaneously without any supply of heat from. without. Keeping the temperature without exceeding 80 is obtained according to the invention, by suitably choosing, dependently on the quantity and on thequality of the montan wax, the concentration of the nitric acid within the above mentioned limits of 40-50%.
The preliminary treatment of the wax with nitric acid .is interrupted latest after an hour by pouring cold water on the mixture. Subsequently the wax is cleansed with water and thereupon it is oxidized by means of bichromate or chromic acid, without having been previously dried, 1 kg. of sodium bichromate being used to 1 kg. of montan wax of the start.
Owing to its bituminous origin, the montan wax preliminarily treated with nitric acid is oxidized most advantageously as stated in the Polish Patent No. 33,690 according to which, in addition to improved wax, chromic mash for tanning leather is obtained. The quantity of the obtained mash is in this case not so great when compared with the quantity of the obtained improved wax.
The difiiculties connected with the transport of the liquid mash and the inconveniences arising in consequence of the necessity of producing a standard mash of a constant specific weight are overcome according to the invention by the fact that the liquid mash is converted into a powdery dry substance by intensively spraying the liquid mash in a drying chamber through which heated air-is simultaneously passed. One obtains a product which is well soluble in water, is easily transportable and which admits the preparation of mashes of any desired concentration.
I claim:
1. A method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about be- 7 tween 10-50%, so as to cause an exothermic reaction be tween said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above about 80 C.; coo ing said reaction mixture so as to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said reaction mixture; and subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
2. A method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 40-50%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed 16- action mixture; allowing said mixture to react for a period of about one hour while preventing the tempera- "ture thereof from rising above about 80 C.; thereafter introducing cold water into said reaction mixture so as to cool the same sutficieutly to substantially terminate said reaction; separating the thus treated montan wax fromthe remainder of said reaction mixture; and subjecting said separated montanwax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
3. A method for improving montan wax comprising 'the steps of dispersing montan wax in an aqueous soluducing cold water into said reaction mixture so as to cool the same'sufiiciently to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said "reaction mixture; washing said separated montan wax with water so as to remove residual "aqueous nitric acid'therefrom; and subjecting said sepa rated and washed montan wax to the action of an aqueous solution of an oxidizing agent selected from the group consisting of chromic acid and bichromates.
4. Amethod for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 40-50%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above 80 C.; cooling said reaction mixture .4 so as to substantia ly terminate said reaction; separating the thus treated montan wax from the remainder ot said reaction mixture; subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates, so as to improve the quality of said montan wax and simultaneously to form a chromic tanningmash; and separating the thus treated'montan wax from said tanning mash.
5. A method for improving montan wax comprising the steps of dispersing montan wax in an aqueous solution of nitric acid having a concentration of about between 4050%, so as to cause an exothermic reaction between said montan wax and said aqueous nitric acid, thereby raising the temperature of the thus formed reaction mixture; allowing said mixture to react for a period up to one hour while preventing the temperature thereof from rising above about C.; cooling said reaction mixture so as to substantially terminate said reaction; separating the thus treated montan wax from the remainder of said reaction mixture; subjecting said separated montan wax to the action of an oxidizing agent selected from the group consisting of chromic acid and bichromates, so as to improve the quality of said montan wax and simultaneously to form a chromic tanning mash; separating the thus treated montan wax from said tanning mash; and spray drying the thus separated tanning mash so as to transform the same into a powdery dry substance.
References Cited in the file of this patent UNITED STATES PATENTS 1,092,629 Barmstedt Apr. 7, 1 914 FOREIGN PATENTS 33,690 Poland Feb. 15, 1950 39,139 Poland Apr. 30, 1956 305,552 Great Britain Feb. 5, 19 29
Claims (1)
- 5. A METHOD FOR IMPROVING MONTAN WAX COMPRISING THE STEPS OF DISPERSING MONTAN WAX IN AN AQUEOUS SOLUTION OF NITRIC ACID HAVING A CONCENTRATION OF ABOUT BETWEEN 40-50%, SO AS TO CAUSE AN EXOTHERMIC REACTION BETWEEN SAID MONTAN WAX AND SAID AQUEOUS NITRIC ACID, THEREBY RAISING THE TEMPERATURE OF THE THUS FORMED REACTION MIXTURE; ALLOWING SAID MIXTURE TO REACT FROM A PERIOD UP TO ONE HOUR WHILE PREVENTING THE TEMPERATURE THEREOF FROM RISING ABOVE ABOUT 80*C.; COOLING SAID REACTION MIXTURE SO AS TO SUBSTANTIALLY TERMINATE SAID REACTION; SEPARATING THE THUS TREATED MONTAN WAX FROM THE REMAINDER OF SAID REACTION MIXTURE; SUBJECTING SAID SEPARATED MONTAN WAX TO THE ACTION OF AN OXIDIZING AGENT SELECTED FROM THE GROUP CONSISTING OF CHROMIC ACID AND BICHROMATES, SO AS TO IMPROVE THE QUALITY OF SAID MONTAN WAX AND SIMULTANEOUSLY TO FORM A CHROMIC TANNING MASH; SEPARATING THE THUS TREATED MONTAN WAX FROM SAID TANNING MASH; AND SPRAY DRYING THE THUS SEPARATED TANNING MASH SO AS TO TRANSFORM THE SAME INTO A POWDERY DRY SUBSTANCE.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PL2971813X | 1956-10-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2971813A true US2971813A (en) | 1961-02-14 |
Family
ID=20059222
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US688140A Expired - Lifetime US2971813A (en) | 1956-10-16 | 1957-10-04 | Treatment of montan wax with chromic acid and simultaneous formation of chromic tanning mash |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2971813A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3232695A (en) * | 1966-02-01 | Process for dyetng materials based on polyamedes and composithons therefor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1092629A (en) * | 1914-03-02 | 1914-04-07 | Wachs Und Cerosinwerke Zu Hamburg J Schlickum & Co | Process for refining and decolorizing mineral wax. |
| GB305552A (en) * | 1927-09-05 | 1929-02-05 | Ig Farbenindustrie Ag | Improvements in the manufacture and production of valuable products from montan wax |
-
1957
- 1957-10-04 US US688140A patent/US2971813A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1092629A (en) * | 1914-03-02 | 1914-04-07 | Wachs Und Cerosinwerke Zu Hamburg J Schlickum & Co | Process for refining and decolorizing mineral wax. |
| GB305552A (en) * | 1927-09-05 | 1929-02-05 | Ig Farbenindustrie Ag | Improvements in the manufacture and production of valuable products from montan wax |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3232695A (en) * | 1966-02-01 | Process for dyetng materials based on polyamedes and composithons therefor |
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