Abstract:
Process for the conversion of heavy feedstocks selected from heavy crude oils, distillation residues, heavy oils coming from catalytic treatment, thermal tars, oil sand bitumens, various kinds of coals and other high-boiling feedstocks of a hydrocarbon origin known as black oils, by the combined use of the following three process units: hydroconversion with catalysts in slurry phase (HT), distillation or flash (D), deasphalting (SDA), comprising the following steps: • mixing at least part of the heavy feedstock and/or at least most of the stream containing asphaltenes obtained in the deasphalting unit with a suitable hydrogenation catalyst and sending the mixture obtained to a hydrotreatment reactor (HT) into which hydrogen or a mixture of hydrogen and H 2 S is charged; • sending the stream containing the hydrotreatment reaction product and the catalyst in dispersed phase to one or more distillation or flash steps (D) whereby the different fractions coming from the hydrotreatment reaction are separated; • recycling at least part of the distillation residue (tar) or liquid leaving the flash unit, containing the catalyst in dispersed phase, rich in metal sulfides produced by demetallation of the feedstock and possibly coke, to the deasphalting zone (SDA) in the presence of solvents, optionally also fed with at least a fraction of the heavy feedstock, obtaining two streams, one consisting of deasphalted oil (DAO) and the other containing asphaltenes, characterized in that a fraction of the stream containing as phaltenes, coming from the deasphalting section (SDA), called flushing stream, is sent to a treatment section with a suitable solvent for the separation of the product into a solid fraction and a liquid fraction from which said solvent can be subsequently removed.
Abstract:
The present invention relates to the use of a silicon-based porous catalytic system for oligomerising light olefins said porous silicon-based catalytic system having an average pore diameter of between about 1 nm and about 5 nm and an acidity level of between about 150 µmol/g and about 650 µmol/g, and prepared from at least one hydrolysable silicon-based compound, or other source of silicon, and at least one non-ionic surface active agent.The invention also relates to a process for oligomerising light olefins using said silicon-based porous catalytic system, and to certain silicon-based porous catalytic systems.
Abstract:
In the processes for the synthesis of alkyl-tert-butyl ethers by reacting the isobutene contained in a C4 charge with a high butadiene content with aliphatic alcohols, to the purpose of preventing polymerization phenomena in the step of separation of alkyl-tert-butyl ether product from the other unreacted components, the initial C4 charge and/or the aliphatic alcohol are submitted to an oxygen removal step, to the purpose of removing all of dissolved free oxygen, down to a maximum residual content of 1-2 ppm.
Abstract:
Process for the psychrophile biological purification of waste waters with medium-low concentrations of polluting substances, consisting in a first anaerobic treatment with an expanded mud bed of U.A.S.B. type at a low flow rate, in a second, fluid-bed treatment on a fine support at a high flow rate, and in an end, aerobic treatment for the nitrification and the end oxydation of the various substances reduced in the previous treatments, then recycled to the upstream steps for the removal of possible nutrients, such as nitrogen and phosphorus.
Abstract:
The mutual condensation of aromatic and carbonylic compounds is carried out with zeolitic materials derived from silicalite by replacing a portion of silicon with B and Al, Al and Ti, Ti and Fe, and with ZSM-5, to yield diaryl-alkanes.
Abstract:
A tank furnace for the metallurgical treatment of non-ferrous metals, consisting of a refractory hearth in the form of an inverted arch disposed on perimetral plate assemblies which are able to move in order to compensate for hearth expansion, a containing belt formed of metal box elements, and walls and a crown of refractory material, said elements being separately supported by an external frame and being able to slide relative to each other due to thermal expansion.
Abstract:
In producing t-butyl alkyl ethers by etherifying with aliphatic alcohols isobutene in a hydrocarbon feedstock containing butadiene in addition to the isobutene, the increase in the pressure drop in the etherification reactor(s) that is due to the butadiene is eliminated by feeding the reactants from the bottom upwards. The reactors preferably contain an acidic ion-exchange resin catalyst.
Abstract:
An improved process is disclosed for preparing gases containing hydrogen and nitrogen and which is especially suitable for the synthesis of ammonia. Using natural gas or virgin naphtha as the starting materials, the reforming reaction with steam takes place in two serially arranged stages, the first of which occurs at an inlet temperature of from 400 DEG C. to 650 DEG C. and an exit temperature of from 650 DEG C. to 750 DEG C., a conversion of from 20% to 50% being effected, the second stage working at an exit temperature of from 750 DEG C. to 850 DEG C. and the conversion being increased up to 70%. Air reforming is carried out under conditions at which the exit temperature of the gas is between 920 DEG C. and 1050 DEG C. and the sensible heat of the effluent gases from the air reforming at such temperature condition is employed to activate the second steam reforming stage. Tube bundle heat-exchangers, the tubes of which are filled with an appropriate catalyst, are used.