SUBSTANCE: invention relates to an improved method for synthesis of 2,6-di-(3,3',5,5'-di-tert.-butyl-4,4'-oxybenzyl)-cyclohexane-1-one used as a stabilizing agent of polyolefins and low-unsaturated carbon=chain rubbers. Method involves interaction of cyclohexanone with N,N-dimethyl-(3,5-di-tert.-butyl-4-oxybenzyl)amine in the ratio = (1-1.2):2, respectively, and process is carried out at temperature 125-145°C up to ceasing isolation of dimethylamine. Method provides simplifying technology and preparing the end product with the yield 61-85.4%.
SUBSTANCE: invention relates to catalytic decomposition of organic hydroperoxides representing important compounds on organic synthesis. Decomposition of cycloalkyl hydroperoxides comprising from 6 to 12 carbon atoms results to formation a mixture of corresponding alcohols and ketones. Process is carried out in the presence of a solvent (alkane, halogen-containing hydrocarbon) at temperature from 20°C to 200°C. Catalyst comprises ruthenium as a catalytically active metal added to a solid carrier chosen from the following group: carbon prepared by pyrolysis of acetylene and metal oxides chosen from the group comprising zirconium, aluminum, lanthanum and manganese. The amount of catalyst expressed as the mole percents of ruthenium to the amount of moles of hydroperoxide to be decomposed is from 0.0001% to 20%. Preferably, the catalyst comprises one additional rare-earth element as a component of alloy. The carrier represents, as a rule, metal oxide with high specific surface above 10 m2/g but preferably, above 100 m2/g that is resistant against oxidation. The hydroperoxide concentration is in the range from 1 to 80 wt.-% with respect to the solution mass. Preferably, hydroperoxide represents cyclohexyl, cyclododecyl, tetraline, ethyl benzene or pinane hydroperoxide and hydrocarbon used in preparing the parent hydroperoxide is used as a solvent. Invention provides the development of the modified catalyst enhancing conversion and selectivity in decomposition of hydroperoxides.
SUBSTANCE: method involves a step for oxidising cyclohexane to obtain cyclohexyl hydroperoxide, a step for catalytic decomposition of cyclohexyl hydroperoxide on a heterogeneous catalyst to obtain a mixture of cyclohexanol and cyclohexanone and a step for distilling cyclohexane, carried out at high temperature and pressure. Said steps form a single circulation loop in which the reaction mixture is circulated through transfer of cyclohexane vapour from the boiler of the distillation apparatus into an oxidation reactor, as well as due to subsequent spontaneous overflow under gravitational forces of the liquid reaction mixture from the oxidation reactor to a decomposition reactor and then into the boiler of the distillation apparatus. The cyclohexane oxidation reactor lies over the cyclohexyl hydroperoxide decomposition reactor which is on the same level as or below the level of the boiler of the distillation apparatus. Conversion of cyclohexane in the oxidation zone is not more than 1.0 mol % and conversion of cyclohexyl hydroperoxide in the decomposition zone is not less than 90.0 mol %.
SUBSTANCE: invention relates to catalyst for dehydration of cyclohexanol to cyclohexane and to method of its production. Proposed catalyst comprises the following components in wt %: calcium carbonate - 16.4-37.0, graphite - 1.0-3.0, and zinc oxide making the rest. Proposed method comprises preparing reaction mix of previously mentioned composition containing sources of zinc oxide and calcium carbonate, moulding, drying, and calcinating. Note here that said mix comprises the following components in wt %: calcium carbonate - 12.4-29.8, carboxymethylcellulose or methylcellulose - 0.1-1.0, and base zinc carbonate making the rest, while graphite is added into amounts sufficient for production of said catalyst.
EFFECT: method increases overall selectivity of converting cyclohexane to cyclohexanone and cyclohexanol and also considerably reduces formation of by-products.
SUBSTANCE: invention relates to a method of preparing a mixture of cyclohexanol and cyclohexanone which are intermediate products in production of polyamides nylon-6 and nylon-6.6. The method is realised at high temperature and high pressure and involves the following successive cycles: oxidation of cyclohexane - decomposition of cyclohexylhydroperoxide, wherein oxidation of cyclohexane and decomposition of cyclohexylhydroperoxide are carried out in separate series-connected reactors without intermediate separation of the aqueous phase, whereby in each separate cycle, cyclohexane is oxidised with air or an oxygen-containing gas in liquid phase in the absence of a catalyst until conversion of cyclohexane of not more than 1.5 mol %, and the cyclohexylhydroperoxide formed during oxidation of cyclohexane is decomposed on a heterogeneous catalyst in a separate reactor until conversion of not less than 90 mol %.
Arctander suggests other uses: “It finds its way more into fragrances rich in woody notes, including those employing newer derivatives of Cyclohexanol, etc.
Practically, if the cyclohexanol content of KA oil is higher than cyclohexanone, it is more likely(economical) to be converted into adipic acid, and the reverse case, caprolactam production is more likely.
This also makes cyclohexane the most stable of the cycloalkanes and therefore will produce the least amount of heat when burned compared to the other cycloalkanes.
If cyclohexane is mono-substituted with a large substituent, then the substituent will most likely be found attached in an equatorial position, as this is the slightly more stable conformation.
SUBSTANCE: invention relates to a method of producing cyclohexanone from cyclohexane, involving the following stages: oxidation of cyclohexane to hydroperoxide of cycohexyl with oxygen in the absence of a catalyst, purification of the reaction medium by washing with water, decomposition of hydroperoxide of cycohexyl to cyclohexanol and cyclohexanone in the presence of a catalyst, extraction of the cyclohexanol/cyclohexanone mixture for separating unreacted cyclohexane and separation of products with boiling point higher than that of the cyclohexanol/cyclohexanone mixture, dehydrogenating cyclohexanol contained in the cyclohexanol/cyclohexanone mixture, in the presence of a dehydrogenation catalyst, distillation of the obtained mixture so as to obtain first run (F1) at the first stage, containing compounds with boiling point lower than that of cyclohexanone, and a last run (Q1) and distillation of the last run (Q1) to obtain a first run (F2) at the second stage, formed from cyclohexanone, and a last run (Q2).