A modular extraction column. End blocks respectively have a flange on one side. A body block includes a plurality of column modules stacked on each other and coupled to the flanges of the end blocks in a surface contact manner. Each column module includes first and second module flanges provided on opposite ends and an accommodating portion provided in an inner portion to have a predetermined area. The column modules are coupled to each other such that the first module flange of one column module faces the second module flange of an adjacent column module. An inner structure is received in the accommodating portions of the plurality of column modules to distribute a fluid. The end blocks and the body block communicate with each other. The accommodating portion of each of the column modules has a quadrangular cross-section in a direction perpendicular to a longitudinal direction thereof.

The present disclosure relates to an improved sieve tray assembly for a liquid-liquid treating column. The tray is a modular design with inlet and outlet downcomer assemblies that are mounted flush to or raised above the sieve deck upper surface. The raised downcomer assemblies provide increased surface area for light liquid upflow perforations and enhanced liquid-liquid contacting capacity and efficiency.

In an improved fiber-film type contactor/separator an enhanced coalescing zone is provided by the presence of a disengagement device connected to a shroud that contains a bundle of high surface area vertical hanging fibers, where the enhanced coalescing zone diverts a portion of an admixture of immiscible liquids to flow radially in a path not parallel to the vertical axis of the hanging fibers whereby the diverted portion of liquids contacts a coalescing surface to cause at least one of the liquids to coalesce into droplets. The immiscible liquids are allowed to settle into separate phase layers and first and second outlets selectively remove the higher density liquid from the lower density liquid.

A method for producing an aromatic bisimide includes reacting a dialkali metal salt of a dihydroxy aromatic compound with a reactive substituted phthalimide under conditions effective to form a product mixture, introducing the product mixture to a liquid-liquid extraction column including an aqueous alkali metal hydroxide solution, and recovering from the liquid-liquid extraction column a purified aromatic bisimide having less than 500 ppm of residual dialkali metal salt of the dihydroxy aromatic compound, the corresponding dihydroxy aromatic compound, the corresponding mono-substituted salt of the dihydroxy aromatic compound, or a combination including at least one of the foregoing. A method for the manufacture of a polyetherimide from an aromatic bisimide prepared by the above method is also disclosed. A polyetherimide having less than 100 ppb of residual bisphenol A and an article made therefrom are also described.

The invention involves an integrated process in which a hydrocarbon feedstock is treated with a caustic (alkaline) extraction to remove sulfides, disulfides, and mercaptans. These extracted materials are further treated, and are then used to activate hydrotreating catalysts.

The present invention relates to a method of recovering (meth)acrylic acid and an apparatus used for the recovery method. The recovery method according to the present invention discharges each (meth)acrylic acid aqueous solution of different concentrations at a (meth)acrylic acid absorption tower, and uses an extraction solvent of a specific ratio in the step of extracting (meth)acrylic acid, thus enabling the operation of a continuous process of recovering (meth)acrylic acid that can secure a high (meth)acrylic acid recovery rate, and can simultaneously significantly reduce purification energy cost.

The present invention describes a liquid-liquid extraction column with perforated plates and overflows, the plates also being equipped with an additional friction element which makes it possible to increase the thickness of the layer of coalesced matter and to guarantee a counter-current flow of the continuous and dispersed phases.

A method for separating an alkyl aromatic hydrocarbon, the method having a step of adding a first diluent and an extractant having a superacid to a mixture comprising the alkyl aromatic hydrocarbon and one or more isomers thereof to carry out an acid-base extraction to thereby form a complex of the alkyl aromatic hydrocarbon with the superacid, and thereafter separating the complex from the mixture, and a step of adding an eliminating agent having a relative basicity in a range of 0.06 to 10 with respect to the alkyl aromatic hydrocarbon and a second diluent to the complex, and carrying out complex exchange of the alkyl aromatic hydrocarbon for the eliminating agent to thereby separate the alkyl aromatic hydrocarbon from the complex.

The present invention relates to process and apparatus for removing aldehydes from acetone. More specifically, the present invention relates to a process and apparatus for removing aldehydes from acetone by reacting the aldehydes with caustic in an acetone column and washing the organic phase with a plurality of water streams.

A reaction column comprises a plurality of cells each of which has a lower cell portion and an upper cell portion. The cells are arranged sequentially, from an uppermost cell to a lowermost cell. The fuel inlet is configured to direct fluid through the reaction column from a lower cell portion of the lowermost cell to an upper cell portion of the uppermost cell, and out of the fuel outlet. The reagent inlet is configured to direct reagent through the reaction column from the upper cell portion of the uppermost cell to the lower cell portion of the lowermost cell. The plurality of cells may be vertically or horizontally positioned, as well as inclined and the like. Systems and methods are likewise disclosed.