Abstract: The present invention relates to a method for producing a C4-C10 alkyl (meth)acrylate, by direct esterification of (meth)acrylic acid by the corresponding alcohol, the reaction water being removed in the form of an azeotrope with the esterification alcohol from a distillation column mounted over the esterification reactor comprising a cationic resin as a catalyst. Said method is characterized in that the molar ratio of alcohol to acid at the inlet of the reactor is between 1.4 and 3, and in that the crude reaction mixture circulates in a recirculation loop joining the reactor and the water removal column, at a recirculation rate of between 6 and 25, expressed by the mass ratio between the flow fed into the loop and the flow sent to a purification treatment.

Abstract: The subject matter of the present invention is an improvement in the continuous production of methyl (meth)acrylate or of ethyl (meth)acrylate by direct esterification of (meth)acrylic acid with methanol or ethanol, under reaction conditions for which the acid is in excess relative to the alcohol, in particular with an acid/alcohol molar ratio of between 1.0 and 4, and under a pressure ranging from atmospheric pressure to 5 bar. The process of the invention makes it possible to minimize the formation of ethyl ethoxypropionate during the esterification reaction, and results in an improvement in the material balance, simplification of the purification train for the desired ester, and optimization of the energy balance.

Abstract: The present invention relates to methods by which the thermal dissociation of Michael adducts present in a stream of crude acrylic acid, called “crude ester grade”, and the esterification reaction of acrylic acid present in the stream of crude acrylic acid, or generated in situ by thermal dissociation, with a light alcohol, are carried out simultaneously.

Abstract: The invention relates to a liquid-liquid extraction process, comprising: the provision of a main input liquid stream, comprising at least one compound of interest and an excess compound; the provision of a liquid scrubbing stream; the extraction of the excess compound from the main input liquid stream by contact with the liquid scrubbing stream, making it possible to collect a main output liquid stream, depleted in excess compound with respect to the main input liquid stream; in which: the main input liquid stream and the liquid scrubbing stream exhibit a difference in density of less than or equal to 50 kg/m3 and also an interfacial tension of less than or equal to 3 dyn/cm; and the extraction stage is carried out in a packed contactor with a ratio by weight as input liquid scrubbing stream/main liquid stream ranging from 0.3 to 0.5.

Abstract: An adjustable radiofrequency filter in planar technology comprises at least one dielectric substrate and n resonators R1, R2, . . . Ri, . . . Rj, . . . Rk, . . . Rn integrated into the substrate, and each resonator comprises, on a principal plane PL of the substrate, a succession of segments t1, t2, . . . tq, . . . tp of planar transmission lines each having two ends, p being the number of segments of planar transmission lines of the resonator Ri considered, p being equal to or greater than 2, q being the rank of the segment, an end of a segment tq of a resonator Ri being opposite and separated by a distance d from an end of the next segment t(q+1) of the same resonator Ri, the opposite ends of the successive segments of a resonator Rq being linked by an electrical link which locally raises the characteristic impedance of the resonator Ri considered.

Abstract: An adjustable radiofrequency filter in planar technology comprises at least one dielectric substrate and n resonators R1, R2, . . . Ri, . . . Rj, . . . Rk, . . . Rn integrated into the substrate, and each resonator comprises, on a principal plane PL of the substrate, a succession of segments t1, t2, . . . tq, . . . tp of planar transmission lines each having two ends, p being the number of segments of planar transmission lines of the resonator Ri considered, p being equal to or greater than 2, q being the rank of the segment, an end of a segment tq of a resonator Ri being opposite and separated by a distance d from an end of the next segment t(q+1) of the same resonator Ri, the opposite ends of the successive segments of a resonator Rq being linked by an electrical link which locally raises the characteristic impedance of the resonator Ri considered.