Wood resin treatment. Thermal processing of wood. What does wood resin mean?
Author Chemical Encyclopedia b.b. I.L.KnunyantsWOOD RESIN, a complex mixture of organic compounds (molecular weight 60-8000), formed during the pyrolysis of wood. Distinguish between slops WOOD RESIN p. (they are released when the liquid pyrolyzate is separated), soluble (they are in the aqueous layer of the pyrolyzate in a dissolved state), extraction (organic solvents are extracted from the aqueous layer of the pyrolyzate). According to the method of thermodynamic processing of wood WOOD RESIN p. subdivided into pyrolysis (usually obtained in retorts), gas-generating and furnace (obtained in energy-chemical installations - generator furnaces); according to the type of processed wood - into coniferous, deciduous, mixed, as well as from bark. Settling resins are viscous dark brown liquids containing 45-65% phenols, higher fatty acids and high mol. phenolic acids, 10-15% volatile fatty acids (from C 2 to C 7) and 25-30% neutral substances. During the distillation of resins, 30-60% of wood-tar oils are formed, the bulk of which boils away at 180-330 ° C (contain 50-60% phenols, 20-30% neutral substances and 5-15% acids); non-volatile residue (30-50%) - wood pitch. Among the phenols of oils - 10-15% monoatomic, 20-40% diatomic (pyrocatechol, guaiacol and their alkyl derivatives) and 20-45% derivatives of trihydric phenols (mainly partial methyl esters of pyrogallol and its homologues). In resins from wood conifers contains less trihydric phenol derivatives and significantly more dihydric phenol derivatives than leaf wood resins. breeds. Neutral substances consist of cyclic aldehydes, ketones and alcohols, full ethers of phenols, hydrocarbons. Among the acids are acetic, propionic, butyric, isovaleric, caproic, enanthic, palmitic, etc. Peck contains 60-80% high mol. phenolic acids, as well as condensation products of phenols with aldehydes.
Soluble resins contain, counting on an anhydrous substance, 25-30% carbohydrates (levoglucosan and other hexose anhydrides), up to 30% hydroxy acid lactones, 10-20% volatile acids, 15-25% phenols and their derivatives, etc. By elemental composition are characterized by low C content (approx. 55% versus 75% for sludge resins) and high O content (38% versus 18%). Extraction resins contain at least 30% phenols.
D. s. used as softeners in the regeneration of rubber and as a binder for activated carbons. Saponification product WOOD RESIN c. alkali - an air-entraining and plasticizing additive in the preparation of cement mortars.
To isolate fractions of resin oils with various temperatures the boiling of the resin is dispersed. With periodic dispersal in a vacuum at the same time. 6-12% creosote oil and 20-30% wood-tar inhibitor are obtained by supplying acute superheated steam. With a continuous process in tube furnaces, the inhibitor yield increases by almost 2 times.
Wood-tar creosote oil (fraction 180-260 ° C) is used for antiseptic. impregnation of wood, antiseptic. processing of yuft leather at tanneries instead of toxic diphenyl oxide, for the manufacture of wood-resin phenolic creolin (a mixture of resin oils with an emulsifier - rosin soap), used in the form of an aqueous emulsion for the treatment of sheep and horses from scabies, as well as for disinfection.
The wood-tar inhibitor (fraction 240-310°C) is close to the best inhibitors of autoxidation and polymerization in terms of efficiency and solubility in hydrocarbons. The active principle is mainly dimethyl ethers of alkylpyrogallols and pyrocatechol derivatives. The inhibitor is used to prevent thermopolymerization of diolefins during their distillation, stabilization of butadiene,
isoprene and other SC monomers, as an antioxidant for gasoline (prevention of carbon deposits in engine cylinders), fuels and oils, to prevent coke formation during thermodynamic processing of petrochemical raw materials, etc.
Soluble resin is processed in the form of an aqueous solution (acidic water) containing 10-30% organic matter. The solution is evaporated to a density of 1.27-1.30 g / cm 3 and a non-phenolic casting binder is obtained, which is processed by heating to improve the quality milk of lime and alkali solution. By evaporation of acidic water, from which phenols were previously extracted, a phenol-free foundry binder is obtained. Fasteners are used as a binder in the manufacture of molds and cores for iron and steel casting, as well as components for improving technology. properties of foundry mixtures. When evaporating the soluble resin at the same time. by oxidizing it with air, WOOD RESIN s. cold curing, to-ruyu in combination with hardeners is used as a binder for cold-hardening core mixtures foundry.
On the basis of the phenolic part of the soluble (extraction) resin, a polyphenolic wood chemical viscosity reducer (PFLH) is synthesized. To do this, the resin is condensed with formaldehyde in an acidic medium at 80 °C. The formed novolac resin is washed hot water to separate neutral substances, dissolve in a 42% NaOH solution and treat with Na oxymethanesulfonate. The resulting alkaline solution is evaporated to a moisture content of not more than 7%, cooled and crushed into crumbs. PFLH is easily soluble in water and alkaline solutions. Its use in the drilling of oil and gas wells provides an improvement in the properties of clay flushing solutions, an increase in the rate of drilling of wells. Liquid PFLH is also used in foundries as an additive to clay-coal suspension, which significantly improves the properties of molding sands and the quality of castings, and reduces the laboriousness of cleaning operations. In ceramic industry, the addition of small amounts of PFLH to dry kaolin can help increase the fluidity of slips and improve the quality of porcelain and faience products.
Acidic water obtained by thermodynamic decomposition in furnaces-generators of spent wood chips from rosin-extraction plants with the addition of wood chips is distilled. Smoke preparations are prepared from the distillate, as well as from the stripped off residue, which are used for smoking meat and fish products. The same residue is used as a binder in the foundry.
Chemical encyclopedia. Volume 2 >> In the past, natural resin was a highly sought-after raw material, it was filled by several specialists - the self-righteous craftsmanship forgotten now was so unfortunate. Even the state economic plans in the so-called period of socialism pushed us to name the course and supply of natural resin. According to Sea Forest, natural resin is a mixture of solid or semi-solid ingredients consisting of carbon, hydrogen and oxygen and aromatic components formed in a water-sealed fabric, but only in organic solvents. They are oxidized by air in the air and harden or polymerize by spraying onto the surface and quickly dissolve the dense oil. In the forest, resin is in a liquid state, the core is hard - except for the blue one, where resin and resin are. Pine responds best to injury, and our ancestors knew this.
A complex mixture of org. compounds (mol. m. 60-8000), formed during the pyrolysis of wood. There are settling D. s. (are released during the separation of the liquid pyrolyzate), solutions (they are in the aqueous layer of the pyrolyzate in a dissolved state), extraction (extracted by organic solvents from the aqueous layer of the pyrolyzate). Thermal method. wood processing D. s. subdivided into pyrolysis (usually obtained in retorts), gas-generating and furnace (obtained in energy-chemical installations - generator furnaces); according to the type of processed wood - into coniferous, deciduous, mixed, as well as from bark. Settling resins are viscous dark brown liquids containing 45-65% phenols, higher fatty to-t and almighty. phenolic acids, 10-15% volatile fatty acids (from C 2 to C 7) and 25-30% neutral in-in. During the distillation of resins, 30-60% of wood-tar oils are formed, osn. the mass of to-rykh boils away at 180-330 ° C (contain 50-60% phenols, 20-30% neutral in-in and 5-15% to-t); non-volatile residue (30-50%) - wood pitch. Among the phenols of oils - 10-15% monohydric, 20-40% dihydric (pyrocatechol, guaiacol and their alkyl derivatives) and 20-45% derivatives of trihydric phenols (primarily partial methyl esters of pyrogallol and its homologues). Pine wood resins contain less trihydric phenol derivatives and significantly more dihydric phenol derivatives than leaf wood resins. breeds. Neutral in-va consist of cyclic. aldehydes, ketones and alcohols, full ethers of phenols, hydrocarbons. Among to-t - acetic, propionic, oily, isovaleric, caproic, enanthic, palmitic, etc. Peck contains 60-80% high mol. phenolic acids, as well as condensation products of phenols with aldehydes.
Soluble resins contain, counting on anhydrous content, 25-30% carbohydrates (levoglucosan and other hexose anhydrides), up to 30% hydroxy acid lactones, 10-20% volatile to-t, 15-25% phenols and their derivatives, etc. According to the elemental composition, they are characterized by a low content of C (approx. 55% versus 75% for settling resins) and a high content of O (38% versus 18%). Extraction resins contain at least 30% phenols.
D. s. used as softeners in the regeneration of rubber and as a binder for activated carbons. Saponification product D. s. alkali - an air-entraining and plasticizing additive in the preparation of cement solutions.
To isolate fractions of resin oils with decomp. boiling point of the resin is dispersed. With periodic distillation in vacuum at the same time. 6-12% creosote oil and 20-30% wood-tar inhibitor are obtained by supplying acute superheated steam. With a continuous process in tube furnaces, the inhibitor yield increases by almost 2 times.
Wood-tar creosote oil (fraction 180-260 ° C) is used for antiseptic. impregnation of wood, antiseptic. processing of yuft leather at tanneries instead of toxic diphenyl oxide, for the manufacture of wood-resin phenolic creolin (a mixture of resin oils with an emulsifier - rosin soap), used in the form of an aqueous emulsion for the treatment of sheep and horses from scabies, as well as for disinfection.
The wood-tar inhibitor (fraction 240-310°C) is close to the best inhibitors of autoxidation and polymerization in terms of efficiency and pH in hydrocarbons. Active beginning - ch. arr. dimethyl ethers of alkyl pyrogallols and pyrocatechol derivatives. The inhibitor is used to prevent thermopolymerization of diolefins during their distillation, stabilization of butadiene,
isoprene and other SC monomers, as an antioxidant for gasoline (prevention of carbon formation in engine cylinders), fuels and oils, to prevent coke formation during thermal. petrochemical processing. raw materials, etc.
R-rimuyu resin is processed in the form water solution(acidic water) containing 10-30% org. in-in. The solution is evaporated to dense. 1.27-1.30 g / cm 3 and get a foundry binder that is not free of phenol, to-ry, to improve quality, it is processed with a load. lime milk and solution of alkali. By evaporation of acidic water, from which phenols are previously extracted, a foundry binder is obtained without phenol. Fasteners are used as a binder in the manufacture of molds and cores for iron and steel casting, as well as components for improving technology. St. in foundry mixtures. When evacuating the p-rimoy resin at the same time. its oxidation by air receive D. of page. cold curing, which, in combination with hardeners, is used as a binder for cold-hardening core mixtures of foundry production.
On the basis of the phenolic part of the p-rim (extraction) resin, a polyphenolic wood chemical is synthesized. viscosity reducer (PFLH). To do this, the resin is condensed with formaldehyde in an acidic medium at 80 °C. The resulting novolac resin is washed with hot water to separate neutral substances, dissolved in 42% NaOH solution and treated with Na oxymethanesulfonate. The resulting alkaline solution is evaporated to a moisture content of not more than 7%, cooled and crushed into crumbs. PFLH is easily soluble in water and alkaline solutions. Its use in the drilling of oil and gas wells provides an improvement in the St-in clay flushing solutions, an increase in the rate of well penetration. Liquid PFLH is also used in foundries as an additive to clay-coal suspension, which significantly improves the properties of molding sands and the quality of castings, and reduces the complexity of cleaning operations. In ceramic industrial addition of small amounts of PFLH to dry kaolin can help increase the fluidity of slips and improve the quality of porcelain and faience products.
Acidic water obtained during thermic. decomposition in furnaces-generators of spent wood chips from rosin-extraction plants with the addition of wood chips, distilled. Smoke preparations are prepared from the distillate, as well as from the evaporated residue, which are used for smoking meat and fish products. The same residue is used as a binder in the foundry industry.
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Use literature for the article "WOOD RESIN":
Uvarov I. P., Gordon L. V., Wood resins, M., 1962; Kiprianov A.I., The process of distillation of wood resin in tube furnaces, M., 1970; Wood-tar and other inhibitors of chain processes, M., 1978; Technology and equipment of wood-chemical industries, 5th ed., M., 1988.
Yu. M. Goldshmidt.
The spruce model is slow but more durable than pine, it lasts for several years. In blue, liquid resin often accumulates in internal soil cracks in soils, so they only suffer from deep wells that kill the tribe's stem. There are no canisters of resin in the tree, and therefore its resin sometimes grew only from tribute to the tribe. Pardons and smells have been documented with us for centuries. The American way of working with resin is, of course.
This place of work, which provided a modest life for the peasants, completely forbade respected authority, and the punishment was filled with strong punishment. We find such records in old indications of the original forests of the Upper Saxon, but also common. Even sometimes a forest man, at that time a "hunter", a man who happened to be in the place of mischief, could literally shoot like a damn shame. However, many people continued to take action in this activity, risking both retribution and subsequent punishment.
Page "WOOD RESIN" prepared according to the materials of the chemical encyclopedia.