Liquid purification or separation – Processes – Making an insoluble substance or accreting suspended...
Patent
1992-12-15
1994-12-13
Hruskoci, Peter A.
Liquid purification or separation
Processes
Making an insoluble substance or accreting suspended...
209 5, 210732, 210778, C02F 154
Patent
active
053727274
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to use of alkyl and/or alkenyl polyalkylene glycol ethers as auxiliaries in the filtration and/or dewatering of mineral and coal suspensions.
Background of the Invention
Suspensions often accumulate in the dressing of ores and have to be dewatered before further processing or disposal. This applies, for example, to mineral concentrates which are obtained by concentration processes, for example by flotation or magnetic separation, and also to coal and tailings from the flotation of coal. For economic reasons, it is desirable that the filtration rate in the subsequent dewatering of the suspensions be as high as possible and that the residual water content of the filter cake be as low possible. Particular difficulties are encountered in the filtration of ores and coals which have a large fine-grain component.
Related Art
It is known that surfactants, such as for example dialkyl sulfosuccinates [U.S. Pat. No. 2,266,954] or alkylphenol polyglycol ethers [Erzmetall 30, 292 (1977)], are suitable as auxiliaries for the dewatering of coal suspensions by virtue of their surface active properties. Where surfactants of the type mentioned are used for the filtration of mineral suspensions, vigorous foaming occurs in the often circulated process water, impeding other concentration processes.
In addition, organic polyelectrolytes, for example polyacrylamides or starch derivatives, may also be used for improving the filtration of mineral and coal suspensions. Although auxiliaries such as these often produce an increase in the filtration rate, the residual water content of the mineral concentrates remains unchanged or is even increased in relation to filtration without filtration aids.
The problem addressed by the present invention was to provide new filtration auxiliaries which could be used without any of the disadvantages mentioned above.
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to the use of alkyl and/or alkenyl polyalkylene glycol ethers corresponding to formula (I) ##STR1## in which R.sup.1 is a linear or branched C.sub.6-22 alkyl and/or alkenyl radical, R.sup.2 is a linear or branched C.sub.1-8 alkyl radical or a benzyl radical, R.sup.3 is hydrogen or a methyl radical and n is a number of 1 to 30, as auxiliaries in the filtration and/or dewatering of mineral and coal suspensions.
The invention is based on the observation that the use of terminated polyglycol ethers of the type mentioned has a beneficial effect on the filtration rate and the residual water content of mineral suspensions and involves very little foaming.
DETAILED DESCRIPTION OF THE INVENTION
Alkyl and/or alkenyl polyalkylene glycol ethers which have particularly advantageous properties in the context of the invention contain 12 to 18 carbon atoms in the substituent R.sup.1 and 4 to 7 carbon atoms in the substituent R.sup.2 and have a value for n of 2 to 10 and preferably 5 to 7 ethylene oxide units.
Alkyl and/or alkenyl polyalkylene glycol ethers are known compounds which may be obtained by conventional methods of preparative organic chemistry. One process for their preparation comprises, for example, reacting adducts of alkylene oxide and primary alcohols with an alkyl or aralkyl halide under the conditions of Williamson's ether synthesis [Fat. Sci. Technol., 89 106 (1987)].
Typical examples of primary alcohols containing 6 to 22 carbon atoms as starting materials for the production of the alkyl and/or alkenyl polyalkylene glycol ethers are caproic alcohol, caprylic alcohol, captic alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol, palmitoleyl alcohol, stearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, gadoleyl alcohol, arachidyl alcohol, behenyl alcohol or erucyl alcohol. In addition, these alcohols may also be present as technical mixtures of the type obtained, for example, by high-pressure hydrogenation of methyl ester fractions based on vegetable and animal raw materials or by hydrogenation of aldehyde cuts from Roelen's oxo synthesis. Te
REFERENCES:
patent: 2266954 (1941-12-01), Bonnet et al.
patent: 4097390 (1978-06-01), Wang et al.
patent: 4156649 (1979-05-01), Quinn et al.
patent: 4385903 (1983-05-01), Moriyama et al.
patent: 4990264 (1991-02-01), Fuller et al.
patent: 5215669 (1993-06-01), Koester et al.
Erzmetall, Band 30, Nr. 7/8, 1977, R. Niessen.
Fat Science Technology, Band 89, Nr. 3, 1987.
R. Piorr et al.: "Low Foaming Biodegradable Nonionic Surfactants", pp. 106-111.
Koeppl Dieter
Koester Rita
Speckmann Horst
von Rybinski Wolfgang
Henkel Kommanditgesellschaft auf Aktien
Hruskoci Peter A.
Jaeschke Wayne C.
Ortiz Daniel S.
Szoke Ernest G.
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