Organic compounds -- part of the class 532-570 series – Organic compounds – Carbohydrates or derivatives
Patent
1996-07-31
1998-10-13
Knode, Marian C.
Organic compounds -- part of the class 532-570 series
Organic compounds
Carbohydrates or derivatives
510470, 510471, 536102, 536105, 536119, C07H 1302, C07H 100
Patent
active
058213600
DESCRIPTION:
BRIEF SUMMARY
THIS APPLICATION IS A 371 OF PCT/EP 95/00227 FILED ON 23 JAN. 1995.
FIELD OF THE INVENTION
This invention relates to a process for the production of polycarboxylates by selective oxidation of polysaccharides with nitrogen dioxide in a fluidized-bed.
RELATED ART
The production of polycarboxylates by oxidative treatment of polysaccharides, for example cellulose, starch and dextrins, is widely known, cf. for example Houben-Weyl "Methoden der organischen Chemie", Thieme-Verlag, Stuttgart (1987), Vol. E 20, Makromolekulare Stoffe, Sub-chapter "Polysaccharid-Derivate (Polysaccharide Derivatives)", by Dr. K. Engelskirchen, loc. cit., pages 2042 et seq., more especially pages 2124 et seq. (Oxidation Products of Cellulose) and pages 2166 et seq. (Oxidized Starches), and "Cellulose Chemistry and its Applications" (1983), John Wiley & Sons, Chichester, GB, more particularly T. P. Nevell, "Oxidation of Cellulose" (Chapter 10) and the extensive literature cited therein, loc. cit., pages 262 to 265.
Broadly speaking, it may be said that there are various oxidizing agents for the oxidation of polysaccharides, more especially polyglucosans synthesized solely from glucose. They include, for example, (atmospheric) oxygen, hydrogen peroxide, sodium hypochlorite or bromite, periodic acid or periodates, lead(IV) acetate, nitrogen dioxide and cerium(IV) salts. These oxidizing agents react very differently with the anhydroglucose units, cf. for example the formula schemes in Houben-Weyl, loc. cit. Pages 2124. For example, periodates or lead(IV) acetate promote C-C cleavage of the anhydroglucose rings. So-called 2,3-dialdehyde cellulose is obtained from cellulose, dialdehyde starch being similarly obtained from starch. It is also known that, where nitrogen dioxide is exposed to the action of cellulose, oxidation of the primary alcohol group to the carboxyl group is by far the predominant reaction. The oxidizing agent, generally present in equilibrium with dinitrogen tetroxide, may be used in gaseous form or in the form of a solution in an inert organic solvent, cf. also Houben-Weyl, loc. cit., page 2125 and the primary literature cited in this connection therein. Starting out from starch also, the primary alcohol group of the anhydroglucose units can be oxidized substantially selectively to the carboxyl group. Thus, the oxidation of starch with gaseous nitrogen dioxide or with nitrogen dioxide dissolved in water or in various organic solvents at room temperature and normal pressure is known from U.S. Pat. No. 2,472,590. Under these conditions, substantially complete conversion of the primary alcohol groups of the polysaccharides into carboxyl groups is only achieved after very long reaction times which, in some cases, can be as long as several days. In addition, large quantities of nitrogen dioxide, based on the polysaccharide to be oxidized, are required in the known processes.
Processes for the production of polycarboxylates by oxidation of polysaccharides with gaseous nitrogen dioxide, which may be carried out in the absence of suspending agents or solvents, are known from International patent application WO 93/16110. The same can also apply to a fluidized-bed process although this does involve the use of intensive mixers. The problem addressed by the present invention was to provide a fluidized-bed oxidation process for polysaccharides which would give oxidation products of consistent quality in a technically dependable manner because the polycarboxylates formed would be potentially suitable as builder or co-builder components for detergents. The same also applies to the salts of such polycarboxylates, more particularly their water-soluble salts, because the use of oxidized polysaccharide compounds for boosting the performance of detergents and/or cleaning compositions has basically been known for decades and has been repeatedly investigated, cf. for example Dutch patents NL 69 883 and NL 78 087. The replacement of phosphate-based builder systems by 6-carboxycellulose treated with Lewis acids is described in U.S. Pat.
REFERENCES:
patent: 2472590 (1949-06-01), Kenyon et al.
patent: 3740339 (1973-06-01), MacDonald
patent: 3790561 (1974-02-01), MacDonald
patent: 3967975 (1976-07-01), Idaszak
patent: 4021927 (1977-05-01), Idaszak
patent: 4820439 (1989-04-01), Rieck
patent: 5541316 (1996-07-01), Engelskirchen et al.
Houbel-Weyl "Methoden der organischen Chemie", Thieme-Verlag, Stuttgart (1987), vol. E 20, Makromolekulare Stoffe, Sub-chapter Polysaccharid-Derivate (Polysaccharide Derivatives), by Dr. K. Engelskirchen, loc. cit., p. 2042 et seq., more especially p. 2124 et seq. (Oxidation Products of Cellulose) and p. 2166 et seq. (Oxidized Starches).
Cellulose Chemistry and its Applications (1983), John Wiley & Sons, Chichester, GB, "Oxidation of Cellulose"(Chapter 101.) P. Nevell, and the extensive literature cited therein, loc. cit. pp. 262-265.
Beranek/Rose/Winterstein, Gundlagen der Wirbelschichttechnik, Krauskopf-Verlag, 1975, p. 72. (Figure only).
The Carbohydrates ed. by Ward Pigman. Academic Press, Inc., pp. 354-355, 1957.
Engelskirchen Konrad
Fischer Herbert
Juettner Werner
Moeller Thomas
Verholt Hans-Wilhelm
Henkel Kommanditgesellschaft auf Aktien
Jaeschke Wayne C.
Knode Marian C.
Lee Howard C.
Ortiz Daniel S.
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