Abstract: The invention relates to the manufacture of alkyl acrylates by direct esterification of acrylic acid with the corresponding alcohol. In particular, the invention relates to the use of a cracker in combination with a topping column equipped with a side draw-off allowing a stream rich in acidic impurities such as ?-hydroxypropionic acid and ?-acryloxypropionic acid to be drawn off during distillation of the crude reaction mixture, so as to produce an acrylic ester meeting purity standards compatible with its use for preparing acrylic polymers.

Abstract: The invention relates to the production of (meth)acrylic esters according to a process by direct esterification, and in particular to the purification of a crude reaction mixture comprising a C4-C12 (meth)acrylic ester using a dividing wall column employed in a particular configuration. The dividing wall column is equipped with a separating wall creating separation zones in the column, the wall not being joined to the upper dome of the column in the top part and being joined to the bottom of the column in the bottom part. The process according to the invention guarantees a product of very high purity, independently of the back-cracking reactions of the heavy by-products liable to arise during the purification of the product sought.

Abstract: The invention relates to the production of (meth)acrylic esters according to a process by direct esterification, and in particular to the purification of a crude reaction mixture comprising a C4-C12 (meth)acrylic ester using a dividing wall column employed in a particular configuration. The dividing wall column is equipped with a separating wall creating separation zones in the column, the wall not being joined to the upper dome of the column in the top part and being joined to the bottom of the column in the bottom part. The process according to the invention guarantees a product of very high purity, independently of the back-cracking reactions of the heavy by-products liable to arise during the purification of the product sought.

Abstract: The subject of the present invention is a process for the synthesis of C1-C10 alkyl (meth)acrylates, by direct esterification of the (meth)acrylic acid by the corresponding alcohol, the reaction being carried out in a fixed bed membrane reactor under conditions in which the water generated by the reaction is eliminated from the reaction mixture as it is formed. The process according to the invention may operate under conditions for which the reagents are not in excess, thereby minimizing the size and energy of the equipment for separation/recycling of the streams generated during the purification of the reaction medium.

Abstract: The invention relates to a method for producing alkyl (meth)acrylate comprising a linear or branched alkyl chain comprising 4 to 10 carbon atoms, by direct esterification of (meth)acrylic acid with a linear or branched alcohol comprising 4 to 10 carbon atoms in the presence of a catalyst, leading to formation of a reaction mixture comprising the desired ester, unreacted acid and alcohol, light by-products, and heavy by-products. The mixture undergoes purification treatment by separation means to obtain purified alkyl (meth)acrylate. The purification treatment comprises a step of membrane separation dehydration applied to at least one of the following: the stream subjected to the final distillation leading to the recovery of the purified (meth)acrylic ester, the aqueous stream originating from the settling out of the reaction mixture, or the stream resulting from the distillation of the light by-products present in the reaction mixture.

Abstract: The subject of the present invention is a process for the synthesis of C1-C10 alkyl (meth)acrylates, by direct esterification of the (meth)acrylic acid by the corresponding alcohol, the reaction being carried out in a fixed bed membrane reactor under conditions in which the water generated by the reaction is eliminated from the reaction mixture as it is formed. The process according to the invention may operate under conditions for which the reagents are not in excess, thereby minimizing the size and energy of the equipment for separation/recycling of the streams generated during the purification of the reaction medium.

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 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 present invention relates to the production of (meth)acrylic esters, and more particularly the production of C4-C10 alkyl (meth)acrylates comprising the step of membrane separation dehydration of at least one stream generated during the purification of alkyl (meth)acrylate.

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.