Abstract: Disclosed is a method of making 5-formyl-2-furoic acid and furan-2,5-dicarboxylic acid. The method involves the use of 5-keto-aldonic acids as intermediates, as these can be subjected to ring formation by a cyclodehydration reaction under mild conditions. The 5-formyl-2-furoic acid or carboxylic derivative thereof is subjected to oxidation so as to form furan-2,5-dicarboxylic acid. The 5-keto-aldonic acid intermediates can be obtained by isomerization of uronic acids which can be obtained from sugar beet pulp, chicory pulp, fruit peals including orange peels, or non-terrestrial sources like seaweeds. A preferred source is sugar beet pulp.

Abstract: Disclosed is a method of making 5-formyl-2-furoic acid and furan-2,5-dicarboxylic acid. The method involves the use of 5-keto-aldonic acids as intermediates, as these can be subjected to ring formation by a cyclodehydration reaction under mild conditions. The 5-formyl-2-furoic acid or carboxylic derivative thereof is subjected to oxidation so as to form furan-2,5-dicarboxylic acid. The 5-keto-aldonic acid intermediates can be obtained by isomerization of uronic acids which can be obtained from sugar beet pulp, chicory pulp, fruit peals including orange peels, or non-terrestrial sources like seaweeds. A preferred source is sugar beet pulp.

Abstract: Disclosed is the oxidation of uronic acids, such as galacturonic acid, to the corresponding aldaric acids (characterized by the formula HOOC—(CHOH)n-COOH, with n being an integer of from 1 to 5) such as galactaric acids. The starting material comprising the uronic acid is subjected to oxygen under the influence of a supported gold catalyst and in the presence of a base. The oxidation occurs in good selectivity and yield, under unexpectedly mild conditions. A source of galacturonic acids is pectin, such as that derived from sugar beet pulp.

Abstract: Disclosed is the oxidation of uronic acids, such as galacturonic acid, to the corresponding aldaric acids (characterized by the formula HOOC—(CHOH)n-COOH, with n being an integer of from 1 to 5) such as galactaric acids. The starting material comprising the uronic acid is subjected to oxygen under the influence of a supported gold catalyst and in the presence of a base. The oxidation occurs in good selectivity and yield, under unexpectedly mild conditions. A source of galacturonic acids is pectin, such as that derived from sugar beet pulp.

Abstract: A next textile treatment where the present method can be used to remove contaminants from the textile concerns rewashing. As already observed above, after dyeing textile with reactive dyestuffs, a considerable amount of dyestuff, particularly hydrolyzed dyestuff, is left behind on the textile. Because the hydrolyzed dyestuff is not fast to washing, it should be removed to provide a textile with sufficient washing fastness. In a rewashing treatment of textile dyed with reactive dyestuff, the textile is first rinsed with water to remove alkali and salt. Thereupon, it is rewashed, with the fructan polycarboxylic acid being metered in the form of a 25-40% solution in an amount of 1-3 g/l of water. Rewashing preferably takes place at a temperature of 95-100° C. for a period of 10-30 minutes. After rewashing, the textile is again rinsed with water to remove residues of the hydrolyzed reactive dyestuff.

Abstract: Heavy metals including lead, copper, zinc, and cadmium, are effectively extracted from sludge mixtures by treatment of the mixture with carboxyl derivatives of fructans, having a degree of substitution of 0.2-3.0.

Abstract: Heavy metals can be effectively complexed with a derivative of a fructan, which derivative contains complexing groups chosen from --X--CY--ZM, --X--CY--ZM, --X--CY--S--S--CY--X--Q, --PY'(--Z'M).sub.2, --SO.sub.3 M and --NR--CH.sub.2 --COOM, where M is a metal or hydrogen, Q denotes the residue of an alcohol or polyol, R is hydrogen or carboxymethyl and X, Y, Y', Z and Z', independently of one another, are O, S or NH and at least one of X, Y and Z is S, with a degree of substitution of 0.1-2.5. The complexing groups are in particular xanthate, xanthide or dithiocarbamate groups.