The invention relates to a process for preparing an ester by alkoxycarbonylation of a C2 to C20 hydrocarbon having at least one multiple bond, preferably having at least one olefinic double bond, in which the homogeneous catalyst system used is separated from the product mixture by means of membrane separation and recycled into the reaction zone. In a development of the present invention, the ester thus formed is converted into another ester by transesterification.

The invention relates to a process for preparing an ester by alkoxycarbonylation of a C2 to C20 hydrocarbon having at least one multiple bond, preferably having at least one olefinic double bond, in which the homogeneous catalyst system used is separated from the product mixture by means of membrane separation and recycled into the reaction zone. In a development of the present invention, the ester thus formed is converted into another ester by transesterification.

The invention relates to a process for the chromatographic purification of a starting stream containing ammonium sulfate and 2-hydroxy-2-methylpropionic acid, comprising: passage of the starting stream through a bed of stationary phase; elution of a raffinate enriched in ammonium sulfate and depleted in 2-hydroxy-2-methylpropionic acid; and elution of an extract enriched in 2-hydroxy-2-methylpropionic acid and depleted in ammonium sulfate.

The invention relates to a process for the chromatographic purification of a starting stream containing ammonium sulfate and 2-hydroxy-2-methylpropionic acid, comprising: passage of the starting stream through a bed of stationary phase; elution of a raffinate enriched in ammonium sulfate and depleted in 2-hydroxy-2-methylpropionic acid; and elution of an extract enriched in 2-hydroxy-2-methylpropionic acid and depleted in ammonium sulfate.

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

This invention relates to the field of contaminated plastic waste decomposition. More specifically, the invention comprises methods and systems to decompose contaminated plastic waste and transform it into value-added products.

The present invention provides a method for preparing an ester-based material, the method including a step in which in a batch reactor, under a catalyst, at least one polycarboxylic acid selected from the group consisting of a terephthalic acid, a phthalic acid, an isophthalic acid, a cyclohexane dicarboxylic acid, a cyclohexane tricarboxylic acid, a trimellitic acid, and citric acid reacts with at least one mono-alcohol having 3 to 12 alkyl carbon atoms, wherein pressure in the reactor is configured such that the pressure at the early stage is 0.3 barg to 1.0 barg and the pressure at the latter stage is 0 barg to 0.5 barg, the pressure at the early stage being greater than the pressure at the latter stage, and the early and latter stages are divided based on any one of the time points when reaction conversion rate is 30% to 90%.

The present invention provides a method for preparing an ester-based material, the method including a step in which in a batch reactor, under a catalyst, at least one polycarboxylic acid selected from the group consisting of a terephthalic acid, a phthalic acid, an isophthalic acid, a cyclohexane dicarboxylic acid, a cyclohexane tricarboxylic acid, a trimellitic acid, and citric acid reacts with at least one mono-alcohol having 3 to 12 alkyl carbon atoms, wherein pressure in the reactor is configured such that the pressure at the early stage is 0.3 barg to 1.0 barg and the pressure at the latter stage is 0 barg to 0.5 barg, the pressure at the early stage being greater than the pressure at the latter stage, and the early and latter stages are divided based on any one of the time points when reaction conversion rate is 30% to 90%.

The present disclosure relates to a method and a system for manufacturing an ester-based composition which are characterized in sequentially operating a plurality of batch reactors, and since an ester-based composition is semi-continuously manufactured, the productivity is high and the stability of a batch reactor is secured.

The present disclosure relates to a method and a system for manufacturing an ester-based composition which are characterized in sequentially operating a plurality of batch reactors, and since an ester-based composition is semi-continuously manufactured, the productivity is high and the stability of a batch reactor is secured.