Cellulose destruction by electron-beam-induced heating

An efficient method for producing furfural and other furan derivatives from cellulose was proposed. Radiolytic destruction of cotton cellulose, sulfate and sulfite pine celluloses, and carboxymethylcellulose was studied under electron-beam-induced distillation conditions. The yield of the liquid distillate from cellulose of various origin was about 60%. Furfural and its derivatives with the molecular weight up to 140 were the predominant products. Grinding and preheating of cellulose increase the fraction of furan derivatives in the condensate. The liquid products are partially transformed into high-molecular-weight compounds that are distilled with difficulty and that are involved in the formation of wood charcoal in the yield of about 20%.     

Phase distribution of the products of radiation and postradiation distillation of cellulose

A comparison of the postradiation dry distillation of cellulose and its distillation in the mode of electron-beam radiation heating has shown that irradiation reduces the yield of char and water. Preirradiation of cellulose at doses of 0.2–2.2 MGy stimulates a monotonic increase in the proportion of total organic products in the condensate distilled off during postradiation dry distillation, reducing the proportion of water by one third. Effective distillation of cellulose in the radiation heating mode is observed at a dose rate above ∼1 kGy/s. The condensate distilled off at 1.5–2.5 kGy/s is composed of organic compounds by ∼90% and is characterized by a high density (up to 1.33 g/cm³) and a high refractive index (up to 1.4690).     

Boiling-induced changes in the mechanism of diglyme radiolysis

Boiling intensifies the radiolytic conversion of diglyme since it stimulates the cleavage of the C–O bonds in the excited molecules and the primary radical cations, enhances the radical exchange reactions, and weakens the diglyme regeneration reactions.

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Reduction of 4,4'-Dinitrostilbene-2,2'-disulfonic Acid with Hydrogen on Raney Nickel

Reduction of 4,4'-dinitrostilbene-2,2'-disulfonic acid with hydrogen in aqueous solution on Raney nickel yields a trisazo compound identical to Direct Yellow K dye.     

Influence of Irradiation and Postradiation Storage on the Adhesion of Polyolefins

High Energy Chemistry - The radiolytic surface oxidation of polyethylene and polypropylene in air and in three-phase dispersed systems including water or an aqueous formic acid solution has been...     

Effect of fast electrons on the aggregative stability of aqueous starch solutions

Electron-beam irradiation in air significantly affects the optical absorption and turbidity of aqueous suspensions and hydrogels of starch due to a change in their aggregative stability. The predominant effect of irradiation consists in an increase in the transparency of solutions and the sedimentation of starch. A maximum susceptibility of the starch dispersions and hydrogels to irradiation has been observed at doses below 3 kGy. The effect weakened with the use of a multienergy electron beam because of the appearance of an excess negative charge in micelles, which prevents their coagulation.     

Protein kinase from cotton seeds

A Ca²⁺-dependent protein kinase C, active at pH 6.5–8.0 has been found in cotton seeds for the first time. The localization of the enzyme in the seeds has been established and some of its properties are described (stability in various media, capacity for performing the phosphorylation of various substrates, activation by calcium ions). Highly active preparations of cottonseed protein kinase C have been isolated by biospecific chromatography.Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 255–259, March–April, 1989.     

Formation of furans upon electron-beam heating of cellulose

Similarity between cotton cellulose and sulfate and sulfite pine celluloses in degradation during electron-beam distillation has been shown. The yield of the distillate liquid slightly depends on the type of cellulose and makes up ∼60 wt %. The product liquid contains organic compounds with molecular masses of 32 to 128, of which furfural and its derivatives prevail. Electron-beam distillation can be used as an effective method for the manufacturing of furfural and other furan derivatives from cellulose (along with the traditional pentosan conversion processes). It has been shown that grinding and preheating of cellulose lead to an increase in the proportion of furfural and other furans in the condensates.     

Effect of absorbed dose on the postradiation dry distillation of cellulose and lignin

The postradiation dry distillation of cellulose and lignin has been studied. During the course of irradiation to 3 MGy, the weights of samples remained almost unchanged. The overpoints of lignin and cellulose irradiated at 2.2 MGy decrease by ～80° and ～100°, respectively. A third of the condensate from cellulose and almost a half that from lignin were distilled off at lower temperatures. Thermally unstable compounds are formed in cellulose; these compounds are predominantly converted into furans upon subsequent heating. The distillation of irradiated lignin affords a smaller amount of tar, but it is richer in methoxyphenols. The aqueous organic fraction distilled off has a higher concentration of soluble organic compounds.