Boise Cascade Corporation

Cheng Fan Lo

William Montgomery Hearon

John F Witte

Phenol, ortho-cresol, meta- and para-cresols, guaiacol, vanillin, acetovanillone and other phenols are separated from alkaline pulping spent liquors by extracting the alkaline liquors with a lower aliphatic alcohol having from 2-5 carbon atoms inclusive, separating the solvent and aqueous phases, and thereafter separating the phenols from the solvent phase.

Separating phenols from alkaline pulping spent liquors

Dialdehyde cellulose is produced by reacting cellulose in aqueous medium with meta periodate ion used in a molar ratio of from 1.2 to 12 moles of meta periodate ion per mole of cellulose at a temperature of from 36.degree. to 60.degree. C. and a pH of between 2 and the conversion pH of water soluble meta periodate to water insoluble para periodate, and separating the dialdehyde cellulose product from the reaction mixture.

Process for the production of dialdehyde cellulose from cellulose

Di- and tricarboxy celluloses are hydrolyzed with sulfurous acid in an aqueous medium to a mixture of erythronic acid and glyoxylic acid, in the case of dicarboxy cellulose; to a mixture of meso tartaric acid and glyoxylic acid in the case of tricarboxy cellulose; and to a mixture of these three products, in the case of a feedstock comprising a mixture of di- and tricarboxy celluloses.

Hydrolyzing di- and tricarboxy celluloses with sulfurous acid

Mixtures of oxalic, meso tartaric, glyoxylic and erythronic acids derived particularly from the oxidation of cellulose derivatives are separated from aqueous solutions in which they are contained and from each other by stepwise precipitation with calcium ion at controlled pH. The oxalic acid is precipitated as calcium oxalate at a pH of 0.9 to 2.0; the tartaric acid as calcium meso tartrate at a pH of 2.8 to 4.4; and the glyoxylic acid, as calcium glyoxylate at a pH of 4.5 to 5.4. After each precipitation the water insoluble precipitate is separated from the aqueous mixture in which it is contained. The relatively soluble erythronic acid remains in solution as a free acid, or in the form of its calcium salt.

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Vancouver, WA, United States of America

Cheng Fan Lo