Abstract: The mechanical and thermal properties of aluminum oxide, such as .gamma. alumina, adapted for use as a catalyst or catalyst carrier are improved through a treatment thereof with a silicon compound such as an alkyl orthosilicate in which the aluminum oxide is impregnated with the silicon compound or a solution thereof in a compatible organic solvent whose boiling point is lower than the boiling point of the silicon compound. The impregnated aluminum oxide is dried at a temperature in the range from above the boiling point of the silicon compound to 500.degree. C and is then subjected to controlled oxidation.

Abstract: The mechanical and thermal properties of aluminum oxide, such as .gamma. alumina, adapted for use as a catalyst or catalyst carrier are improved through a treatment thereof with a silicon compound containing hydrolyzable radicals, such as methyl orthosilicate, in which the aluminum compound is impregnated with the silicon compound or a solution thereof in a compatible organic solvent whose boiling point is lower than the boiling point of the silicon compound. The impregnated aluminum oxide is slowly brought to the boiling temperature of the silicon compound in an inert atmosphere so as to cause silicon compound to react with the aluminum oxide and to distill off reaction products and excess silicon compound. The hydrolyzable groups bound to the silicon compound on the aluminum oxide are then reacted with water and distilled off.

Abstract: Urea is produced through an integrated, isobaric process in which raw ammonia synthesis gas, consisting essentially of H.sub.2, N.sub.2 and sufficient CO.sub.2 to produce the urea and compressed to a pressure slightly above the urea synthesis pressure, is decarbonated in a vertical film heat exchanger where it is contacted with a thin aqueous film containing NH.sub.3 with which the CO.sub.2 reacts to produce a concentrated carbamate solution that is withdrawn from the bottom of the exchanger and fed to a urea reactor. The compressed, unreacted synthesis gas containing traces of CO and saturated with NH.sub.3 is withdrawn from the upper part of the heat exchanger, NH.sub.3 is separated therefrom and recycled to the heat exchanger, and the balance of the unreacted synthesis gas is subjected to methanation to eliminate any CO and CO.sub.2 therein.

Abstract: Improved integrated process for simultaneous synthesis of ammonia and urea. Improved yields of urea in purified form are obtained by a simple process which curtails the addition of external water to the process. Two carbon dioxide absorbers are employed. A concentrated ammonium carbonate solution is utilized in the primary carbon dioxide absorber. A secondary carbon dioxide absorber is downstream in series to the first or primary carbon dioxide absorber. An ammonical solution of ammonium carbonate is utilized in the secondary carbon dioxide absorber.

Abstract: A multi-stage process for the solvent extraction of butadiene from a mixed feed stock containing butadiene, C-4 saturated and olefinic hydrocarbons and acetylenic compounds is disclosed wherein the feed stock is contacted with N-formyl morpholine and C-4 saturated and olefinic hydrocarbons are separated therefrom in a first stage and, in a second stage, the solvent and acetylenic compounds present in the feed stock are respectively separated from one another.

Abstract: Nicotinamide 6-(2-hydroxy-3-carboxy-propylamino) purine dinucleotide is prepared by reacting nicotinamide-adenine-dinucleotide with 3,4 epoxybutanoic acid in the presence of perchloric acid to prepare an intermediate wherein the adenine nucleus is alkylated in the N.sub.1 position. That intermediate is subjected to chemical reduction of the nicotinamide ring, followed by rearrangement to yield the end product wherein the amino group in position 6 of the adenine ring is alkylated.

Abstract: A chelated compound of uranium (IV) or thorium is prepared by reacting an anhydrous halide of uranium (IV) or thorium with a chelating agent such as acetylacetone in the presence of an anhydrous solvent and gaseous ammonia in the temperature range of 10 to 60.degree. C.

Abstract: A method is disclosed for preparing tertiary olefins starting from the corresponding tertiary ethers, the improvement consisting in contacting the ether with a catalyst composed by active alumina modified by reaction with a silicon compound selected among those corresponding to the general formula: ##STR1## wherein X,Y,Z and W can be --R, --OR, --Cl, --Br, --SiH.sub.3 , --COOR, --Sih.sub.n O.sub.m, R being hydrogen, an alkyl, cycloalkyl, aryl, aralkyl or alkyl-cycloalkyl radical of from 1 to 30 carbon atoms, n and m being integers comprised between 1 and 3. The advantages afforded by the invention are mainly the nearly quantitative yields and the high purity of the end products.

Abstract: A dioldione represented by the formula: ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, the same or different, represent alkyl, cycloalkyl, arylalkyl, aryl or hydrogen, is prepared by reacting a compound represented by the formula: ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 have the above meanings, with an oxidizing mixture consisting of osmium tetroxide and an alkali or alkali-earth metal chlorate.

Abstract: A thio-derivative of vanadium having the formula: Vcp.sub.2 (SR).sub.n, wherein cp is cyclopentadienyl, R is an alkyl, aryl or cycloalkyl radical and n is 1 or 2, is prepared by reacting vanadium di-cyclopentadiene with a disulphide represented by the formula: S.sub.2 R.sub.2, wherein R has the meaning given above, in the presence of an inert solvent and in the temperature range of from room temperature to the boiling point of the solvent.

Abstract: A plastic material such as a polyethylene which is adapted for use in packaging is rendered photodegradable under the direct action of sunlight by mixing therewith an amount, up to 3% by weight, of an additive consisting of 1.2.4.5 tetramethylbenzene.

Abstract: A new uranium allyl compound, represented by the formula: ##EQU1## WHEREIN R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5, which may be the same or different, are members of the group consisting of H, alkyl radicals containing from 1 to 10 C atoms, aryl radicals containing from 6 to 10 C atoms, cycloalkyl radicals containing from 4 to 10 C atoms, and alkyl aryl radicals containing from 7 to 10 C atoms, the dotted line linking the three carbon atoms indicates possible delocalization of the valence electrons of the double bond, X is an anion selected from Cl.sup.-, Br.sup.- and I.sup.- and n is an integer ranging from 1 to 3. The members of that group of compounds are useful, respectively, as catalysts in the stereospecific polymerization of diolefins and may be prepared by reacting a compound represented by the formula: ##EQU2## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 and the dotted line have the significance given above, with a compound represented by the formulae HX or X.sub.

Abstract: A process is described whereby aluminum chlorohydroxide having a controlled chlorine content is prepared by subjecting a mineral containing aluminum oxide or hydroxide (e.g. bayerite, gibbsite, diaspore, boehmite or alumina bayer) is subjected to a preliminary etching with hydrochloric acid at a temperature in the range from 110.degree. to 150.degree. C, the solution so obtained is neutralized with ammonia and the desired aluminum chlorohydroxide (e.g. Al.sub.2 (OH).sub.5 Cl) is crystallized out.

Abstract: A new catalyst, useful in the homo-, co- and ter-polymerization of monomers of the episulphide, vinylic, lactonic, dimethylketene and aldehyde type, is prepared by reacting a metal selected from groups IA, IIA or IIIA of the periodic system, or a hydride, alkyl or amino derivative thereof (e.g. LiBut) with a compound (e.g. ##EQU1## containing at least two groups selected from SO and SO.sub.2 and constituted by one or more repeating units represented by the formula:R -- (X - (R').sub.m).sub.n --Y -- R"wherein, X and Y, which may be the same or different are chosen from SO and SO.sub.2 ; R and R" are chosen from methyl, alkyl containing 2-10 C atoms, cycloalkyl, aryl, aralkyl, alkylcycloalkyl and bivalent radicals adapted to react together to form a closed ring: R' is chosen from arylenic, cycloalkylenic, alkyl-arylenic, alkyl-cycloalkylenic bivalent radical and a methylenic chain containing from 1 to 20 C atoms; m is 0 or 1; and n is 1, 2 or 3.

Abstract: An additive, adapted to improve the viscosity index of a mineral or synthetic lubricating oil, is prepared from polymeric material of very high viscosity boiling above 175.degree.C, and obtained through polymerization of normal alpha-olefines having the general formula R--CH = CH.sub.2, wherein R is an alkyl radical containing from 2 to 16 carbon atoms, in the presence of a TiCl.sub.4 /polyiminoalane catalyst, in a substantially inert atmosphere which may contain hydrogen up to a manometer pressure of 1 kg/cm.sup.2, by distilling said polymeric material so that the fraction boiling at a temperature below 350.degree.C at atmospheric pressure is removed therefrom, and catalytically hydrogenating the balance thereof to produce the desired end product.

Abstract: A process for producing urea from CO.sub.2 and NH.sub.3 in which the CO.sub.2 and NH.sub.3 are reacted in a reactor, the reaction product is passed into a first stage decomposer maintained at the same pressure as the reactor, the reaction product is contacted in the first stage decomposer with NH.sub.3 to form a urea solution substantially free of CO.sub.2, said urea solution substantially free of CO.sub.2 is passed from the first stage decomposer to a second stage decomposer also maintained at the same pressure as the reactor and is contacted in said second stage decomposer with a stream of inert gas and an aqueous solution of substantially pure urea is withdrawn from the second reactor.

Abstract: A method is disclosed for eliminating carbon from nuclear fuel elements in the reprocessing thereof in a closed system wherein such carbon is caused to combine with hydrogen to form methane in an attack zone, and the methane is then caused to flow from the attack zone to a regeneration zone where it is cracked into carbon and hydrogen.

Abstract: A catalyst useful in the ammoxidation or oxidation of olefins consisting of a mixture of uranium oxide and tellurium oxide wherein the Te/U atomic ratio is in the range from 2 to 5. Also disclosed is a catalyst as defined above which is supported on a carrier.

Abstract: A novel process for making polymers degradable by the direct action of sunlight is disclosed. The process is based on the addition to the polymer of a compound having the formula: ##EQU1## in which R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different and are selected from the group consisting of aromatic radicals with the proviso that one or two of them may be selected from the group consisting of hydrogen, alkyl, cycloalkyl and arylalkyl.

Abstract: A diolefin (isoprene or butadiene) is separated from a mixture thereof with other hydrocarbons by feeding the mixture to an extractive distillation column at a point intermediate its ends and also feeding to that column, at a point adjacent its upper end, an imidazole derivative, such as N-methyl imidazole, which is a solvent for the diolefin, withdrawing substantially all of the other hydrocarbons from the upper end of the column and withdrawing the solvent, substantially all of the diolefin and the balance of the other hydrocarbons as bottom product from that first extractive distillation column. That bottom product is then fed to a second extractive distillation column, the diolefin is withdrawn from its upper end in substantially pure form, the balance of the other hydrocarbons are withdrawn in vapor phase and the solvent is withdrawn from the lower end of the second extractive distillation column for recycle to the first and second extractive distillation columns.