摘要:
A solid catalyst component for the (co)polymerization of α-olefins having general formula (I): ZrnMAlxClMgp (I) wherein: M represents titanium (Ti), vanadium (V), or mixtures thereof; n is a number ranging from 0.01 to 2; x is a number ranging from 0.1 to 4; y is a number ranging from 5 to 53; p is a number ranging from 0 to 15; obtained by means of a process comprising putting at least one zirconium arene in contact with at least one metal compound and, optionally, with at least one compound of magnesium. Said solid catalyst component can be advantageously used as a solid component in a catalyst for the (co)polymerization of α-olefins. Said catalyst can be advantageously used in a process for the (co)polymerization of α-olefins.
摘要:
The invention relates to a process for the production of ethylbenzene which comprises: a reaction step in which benzene is reacted with ethanol, or a mixture of ethanol and ethylene, at a pressure higher than atmospheric pressure, preferably in gaseous phase or in mixed gas-liquid phase, in the presence of a catalytic system containing a zeolite belonging to the BEA family, and a separation step of the product obtained. According to a preferred aspect, ethanol deriving from biomasses is used, in particular ethanol obtained from the fermentation of sugars deriving from biomasses.
摘要:
The present invention relates to a concentrated polymeric composition which comprises: a) vinyl aromatic polymers and/or copolymers in an amount ranging from 10% to 90% by weight, calculated with respect to the overall composition, with respect to the overall composition, b) at least one compound containing epoxy functional groups in an amount ranging from 0.01% to 5% by weight, calculated with respect to the overall composition, with respect to the overall composition, c) at least one infrared absorbing agent, in an amount ranging from 10% to 90% by weight, calculated with respect to the overall composition, with respect to the overall composition.
摘要:
The present invention relates to a process for the production of 1,3-butadiene which comprises the following phases: a) extracting, by means of extractive distillation, in an extraction section, an end-product containing 1,3-butadiene and a raffinate product, starting from mixtures of saturated and unsaturated compounds having from 2 to 10 carbon atoms in the chain; b) sending the raffinate product to a dehydrogenation section; c) dehydrogenating the raffinate product in the dehydrogenation section in the presence of a dehydrogenation catalyst and an inert product so as to form a reaction effluent containing 1,3-butadiene; d) recirculating the reaction effluent containing 1,3-butadiene directly to the extraction section after separating the incondensable compounds.
摘要:
A process for the preparation of a 1,3-butadiene and styrene copolymer comprising the following steps: a) anionically polymerizing a blend comprising from 5% by weight to 40% by weight of styrene and from 60% by weight to 95% by weight of 1,3-butadiene, with respect to the overall weight of the mixture, in the presence of at least one hydrocarbon solvent, of at least one lithium-based catalyst having the general formula LiR1 wherein R1 represents a linear or branched C3-C10 alkyl group, and of least one polar modifier; b) optionally, reacting the copolymer obtained in step (a) with at least one chain-end monomer selected from 1,3-butadiene, styrene and α-methylstyrene; c) reacting from 10% by weight to 70% by weight, preferably from 20% by weight to 50% by weight, of the lithium-terminated polymeric chains present in the copolymer obtained in step (a) or in step (b), with at least one coupling agent selected from liquid polyepoxides having at least three reactive sites capable of reacting with the carbon-lithium chain-ends; d) optionally, reacting the copolymer obtained in step (c) with at least one chain-end monomer selected from 1,3-butadiene, styrene and a-methylstyrene; e) reacting the linear polymeric chains remaining in the copolymer obtained in step (c) or in step (d), with at least one tin compound having the general formula XSn(R2)3 wherein X represents a halogen atom such as, for example, chlorine and R2 represents a linear or branched C1-C10 alkyl group.
摘要:
Process for the alkylation of aromatic hydrocarbons by means of olefins containing from 2 to 8 carbon atoms, which comprises feeding the hydrocarbon, olefin, and possibly water, to the head of a fixed-bed reactor, operating with a “trickle flow” regime, containing at least one layer of a catalyst comprising a medium- or large-pore zeolite.
摘要:
Process for the production in continuous or semi-continuous of phenol/acetone from cumene, via cumene hydroperoxide (CHP), which comprises: a. producing CHP in an air-lift reactor in which at least the upper and/or lower part of the downcomer has a flaring; b. cleaving the cumene hydroperoxide by means of acid treatment in a loop reactor comprising two heat exchangers connected in series and wherein the feedings of CHP and fresh acetone are in pairs and each pair is positioned up-stream of each exchanger.
摘要:
The device of the present invention allows the pressure of a certain fluid to be reduced without reductions in the cross sectional area or organs in movement. The pressure reduction is obtained by passing the fluid to be depressurized, in sequence, through a plurality of pairs of steps. In the first step of each pair, part of the pressure energy of the fluid is converted to gravitational potential; in the second step the gravitational potential is converted into thermal energy, so as to prevent the reconversion of the same into pressure energy.
摘要:
Process for the oxidation of alkylaromatic hydrocarbons to hydroperoxide catalyzed by N-hydroxy derivatives in the presence of a solvent which includes recovering the catalyst from the oxidation mixture by the possible removal of the solvent by distillation and/or cooling of the oxidation mixture, with the consequent precipitation and filtration of the N-hydroxy-derivative catalyst, and adsorption with non-basic adsorbing solids for the substantially complete recovery of the catalyst.
摘要:
Circuit and to a process for managing transients and process and product anomalies in a plant for production of granulated expandable polymers EPS or extruded polymers XPS, said circuit being placed e.g. in a granulation plant along which are positioned:
a mixing device suitable for mixing additives and expanding agent within a stream of molten polymer; a granulator or an extrusion device positioned downstream of said mixing device; a deviation valve suitable for molten polymers placed along the line connecting said mixing device to said granulator or to said extrusion device upstream of said granulator or extruder, said deviation valve being provided with at least one inlet (A), a Stand-by position (A→C) and a Run position (A→B),
said circuit further comprising a heating device downstream of said valve, a separation device downstream of said heating device suitable for physically separating the blowing agent from the polymer and any additives present therein, and a cooling device positioned between said separation device and said mixing device.