摘要:
In the preparation of isoprene by reacting isobutene with formaldehyde to produce 4,4-dimethyl-m-dioxane in a first stage, and decomposing the dioxane to isoprene and formaldehyde in a second stage, formaldehyde in the effluent streams of either or both of said stages is recovered. The formaldehyde-containing liquids are distilled to separate high boilers; the overhead, which is formaldehyde-rich, is extracted with isobutene feed to the process, whereby the isobutene extracts low boilers from the formaldehyde-containing liquid; and the formaldehyde-containing liquid, having at some point after said distillation been treated with an alkaline material, is subjected to rectification to produce as head product, the recovered formaldehyde.
摘要:
Process for the preparation of cycloaliphatic hydrocarbons by gas phase hydrogenation of aromatic hydrocarbons in the presence of palladium catalyst, characterized in that palladium catalyst is used which contains the palladium applied to a support which comprises aluminium oxide of which at least 20% by weight, relative to the weight of the support, has been converted to lithium-aluminium spinel. The gas phase hydrogenation can be carried out at atmospheric pressure.
摘要:
A process for the production of an .omega.-formyl carboxylic acid ester, comprising reacting an enol ether of a cyclic ketone with hydrogen peroxide in the presence of at least one catalyst selected from the group consisting of a compound of boron or of a metal of the Fifth or Sixth Secondary Group of the Periodic Table. Advantageously the enol ether has the formula ##STR1## wherein R.sub.1 is alkyl of 1 to about 3 carbon atoms, cycloalkyl of 5 or 6 carbon atoms or phenyl optionally substituted by fluorine, chlorine, alkoxy of 1 to about 3 carbon atoms, cyano or phenyl,n is an integer of about 3 to 10, andR.sub.2 each independently is hydrogen, fluorine, chlorine, cyano, alkoxy of 1 to about 4 carbon atoms, alkyl of 1 to about 6 carbon atoms, cycloalkyl of 5 to 7 carbon atoms or phenyl optionally substituted by fluorine, chlorine, cyano, alkoxy of 1 to about 4 carbon atoms or alkyl of 1 to about 6 carbon atoms,And the catalyst comprises about 15 to 25 mole % based on the hydrogen peroxide of a boron oxide, a boric acid, a salt of a boric acid, a boron halogen compound, a complex boron compound or a boric acid ester of the formula ##STR2## wherein R.sub.4, R.sub.5 and R.sub.6 each independently is alkyl of 1 to about 6 carbon atoms optionally substituted by hydroxyl, fluorine, chlorine, alkoxy of 1 to about 3 carbon atoms or phenyl, cycloalkyl of 5 to 7 carbon atoms or phenyl optionally substituted by fluorine, chlorine or alkyl of 1 to about 3 carbon atoms,Or about 0.01 to 1 mole % of at least one acetate, benzoate, acetylacetonate or naphthenate of a metal of the Fifth or Sixth Group of the Periodic table.
摘要:
A process for the production of pyrocatechol and hydroquinone by the hydroxylation of phenol in the nucleus with hydrogen peroxide, wherein phenol is reacted at the start of the reaction with substantially anhydrous hydrogen peroxide and wherein the reaction is carried out in the presence of a strong acid.
摘要:
A process has been invented for the preparation of pyrocatechol and hydroquinone which comprises reacting a solution which is substantially anhydrous and free from hydrogen peroxide, of a percarboxylic acid in an inert, organic solvent, with phenol at temperatures from -10.degree. C. to 80.degree. C.The compounds obtained according to the invention are known, important industrial chemicals which are used in large amounts in the field of photography and of dyestuffs and plastics and in the field of scents and flavorings.
摘要:
A process for the production of pyrocatechol and hydroquinone by the hydroxylation of phenol in the nucleus with hydrogen peroxide, wherein phenol is reacted at the start of the reaction with substantially anhydrous hydrogen peroxide and wherein the reaction is carried out in the presence of a strong acid.
摘要:
A process for the production of ketazine corresponding to the general formula ##EQU1## in which: R.sub.1 and R.sub.2 are independently linear or branched alkyl radicals of from 1 to 8 carbon atoms or a phenyl radical, or taken together with the carbon atom to which they are attached represent a carbocyclic ring with 5 to 8 carbon atoms or a cyclic alkyl radical with 5 to 8 carbon atoms, comprising reacting ammonia, hydrogen peroxide and a ketone of the general formulaR.sub.1 - CO - R.sub.2in which R.sub.1 and R.sub.2 are as defined above, in the presence of hydrocyanic acid.
摘要翻译:对应于通式R 1 R 1的制备酮嗪的方法ANGLE C = N-N = C ANGLE R2R2其中:
摘要:
A process for the preparation of hexahydrophthalic acid anhydride which comprises hydrogenation .DELTA..sup.4 -tetrahydrophthalic acid anhydride in the liquid phase at a temperature of from 70.degree. to 150.degree. C. and at a pressure of from 30 to 200 bar in the presence of a catalyst selected from palladium, ruthenium, nickel or mixtures thereof arranged in a fixed bed, wherein the catalyst is applied to a carrier of alumina of which at least 20% by weight has been converted into lithium aluminium spinel and the liquid phase is a mixture of .DELTA..sup.4 -tetrahydrophthalic acid anhydride and hexahydrophthalic anhydride in a proportion by weight of from 1:1 to 1:100.
摘要:
2-Methylpropane-1,3-diol is prepared by reacting 2-methylenepropane-1,3-diol diacetate with a monohydric, lower aliphatic alcohol in the presence of a base. Thereafter the resulting 2-methylenepropane-1,3 diol is catalytically hydrogenated to form 2-methylpropane-1,3-diol.