Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Treatment with particular chemical
Patent
1995-02-06
1997-12-23
Beisner, William
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Treatment with particular chemical
162179, 252321, 252358, D21H 2112, B01D 1904
Patent
active
057003513
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to antifoams for the paper industry, based on an oil-in-water emulsion, in which the oil phase accounts for from 5 to 50% by weight of the emulsion and consists essentially of a mixture of esters of long-chain carboxylic acids and, if required, conventional hydrophobic compounds, such as alcohols of at least 12 carbon atoms, distillation residues which are obtainable in the preparation of alcohols having a relatively large number of carbon atoms by oxo synthesis or by the Ziegler process and which may be alkoxylated, and/or hydrocarbons having a boiling point above 200.degree. C. or fatty acids of 12 to 22 carbon atoms.
The prior unpublished European Patent Application No. 92113458.1 discloses antifoams for the paper industry, based on an oil-in-water emulsion, in which the oil phase accounts for from 5 to 50% by weight of the emulsion and contains least 22 carbon atoms and C.sub.1 -C.sub.36 -carboxylic acids, distillation residues which are obtainable in the preparation of alcohols having a relatively large number of carbon atoms by oxo synthesis or by the Ziegler process and which may be alkoxylated, a mixture of the stated compounds and/or monohydric to trihydric C.sub.1 -C.sub.18 -alcohol and, if required, acid of 12 to 22 carbon atoms at least 20% esterification of a polyglycerol mixture comprising condensation emulsions are efficient antifoams in papermaking even at above 35.degree. C., for example at from 50.degree. to 60.degree. C. In contrast, other known antifoams based on oil-in-water emulsions which are usually used in papermaking become less efficient when the temperature of the aqueous system to be defoamed increases to above 35.degree. C. At even higher temperatures, a more rapid decrease in the efficiency of the antifoams then occurs when the known oil-in-water emulsions are used. Since there is an increasing trend toward closed water circulations in the paper mills, the result is an increase in the temperature of the circulated water in papermaking, so that the efficiency of the antifoams used to date substantially decreases.
It is an object of the present invention to provide antifoams which are still sufficiently efficient even at relatively high temperatures for the water circulations in the paper mills.
We have found that this object is achieved, according to the invention, by antifoams for the paper industry, based on an oil-in-water emulsion, in which the oil phase accounts for from 5 to 50% by weight of the emulsion and consists essentially of the mixture of trihydric C.sub.1 -C.sub.22 -alcohols, of polyglycerols which contain at least 2 glycerol units with at least one C.sub.12 -C.sub.36 -fatty acid and glycols, the molecular weight of the polyalkylene glycols being up to 5,000 g/mol, and, if required, least 22 carbon atoms and C.sub.1 -C.sub.36 -carboxylic acids, distillation residues which are obtainable in the preparation of alcohols having a relatively large number of carbon atoms by oxo synthesis or by the Ziegler process and which may be alkoxylated, a mixture of the stated compounds and/or of 12 to 22 carbon atoms.
Fatty esters of C.sub.12 -C.sub.22 -carboxylic acids with a monohydric to trihydric C.sub.1 -C.sub.22 -alcohol are used as components (a) of the oil phase of the antifoam emulsion. The fatty acids on which the esters are based are, for example, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid and behenic acid. Palmitic acid or stearic acid is preferably used for the preparation of the esters. Monohydric C.sub.1 -C.sub.18 -alcohols, e.g. methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, hexanol, decanol, palmityl alcohol and stearyl alcohol, as well as dihydric alcohols, such as ethylene glycol, propylene glycol, 1,6-hexanediol or 1,4-butanediol, and trihydric alcohols, such as glycerol, may be used for the esterification of the stated carboxylic acids. The polyhydric alcohols may be completely or partially esterified. This class of compounds also includes the naturally occuring vegetable and ess
REFERENCES:
patent: 2346928 (1944-04-01), Lighthipe
patent: 2715614 (1955-08-01), Snook
patent: 2762780 (1956-09-01), Kulakow
patent: 3248289 (1966-04-01), Shinozaki et al.
patent: 3951853 (1976-04-01), Suwala
patent: 4009119 (1977-02-01), Poschmann et al.
patent: 4208301 (1980-06-01), Gammon
patent: 4221600 (1980-09-01), Alexander
patent: 4454113 (1984-06-01), Hemker
patent: 4664844 (1987-05-01), Bergold et al.
patent: 4895681 (1990-01-01), Herrmann et al.
patent: 4976888 (1990-12-01), De Clercq et al.
patent: 5326499 (1994-07-01), Wegner et al.
patent: 5429718 (1995-07-01), Morlino et al.
Chemical Abstract Acc #107:219850 of Melzer et al. DE 3601929 (Jul. 30, 1987).
Dralle-Voss Gabriele
Hohmann Andreas
Oppenlaender Knut
Schuhmacher Rudolf
Wegner Brigitte
BASF - Aktiengesellschaft
Beisner William
LandOfFree
Antifoams based on oil-in-water emulsions for the paper industry does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Antifoams based on oil-in-water emulsions for the paper industry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Antifoams based on oil-in-water emulsions for the paper industry will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1799613