A process for separating or removing permanganate reducing compounds (PRC's) from a first mixture containing at least one PRC, methyl iodide, and water comprises the steps of: feeding the first mixture to a feed port of a distillation column, and distilling and separating the first mixture into an upper stream and a lower stream, wherein the distillation of the first mixture forms a second mixture at an upper position than the feed port, and the process further comprises the steps of: withdrawing the second mixture as the upper stream, and withdrawing the lower stream from a lower position than the feed port.

The present invention discloses a gas distribution structure for a distillation column. Pressure drop adjusting column tray assemblies are arranged in a left mass transfer region and a right mass transfer region along a column height direction. The gas distribution structure includes column trays, gas-rising pipes, downcomers and cover hoods, wherein a gas flow meter is arranged in a pipe of any gas rising pipe; a feeding port and a liquid collecting port are formed in a column wall; a liquid flow meter, an adjusting valve and a circulation pump are arranged on a circulation pipeline between each liquid collecting port and each feeding port; technological parameters are transmitted to a control system; and the circulation pumps and the adjusting valves are controlled by the control system

A method for producing a stream of propylene and associated facility are described. The method includes: an introduction of a feed cut rich in C4 and/or C5 hydrocarbons, and at least one cut rich in ethylene into a metathesis reactor; an introduction of a metathesis product in a deethylenizer; a production of an overhead stream rich in ethylene and a feed stream; an introduction of the feed stream into a depropylenizer and recovery of a bottom stream containing C4+ hydrocarbons; a recovery, from an overhead stream of the depropylenizer, of the propylene stream; a lateral withdrawal of a recycle stream and return of the recycle stream to the metathesis reactor; a lateral draw-off, in the depropylenizer, of a purge rich in C4 paraffinic hydrocarbons and/or rich in isobutene.

A method for producing a stream of propylene and associated facility are described. The method includes: an introduction of a feed cut rich in C4 and/or C5 hydrocarbons, and at least one cut rich in ethylene into a metathesis reactor; an introduction of a metathesis product in a deethylenizer; a production of an overhead stream rich in ethylene and a feed stream; an introduction of the feed stream into a depropylenizer and recovery of a bottom stream containing C4+ hydrocarbons; a recovery, from an overhead stream of the depropylenizer, of the propylene stream; a lateral withdrawal of a recycle stream and return of the recycle stream to the metathesis reactor; a lateral draw-off, in the depropylenizer, of a purge rich in C4 paraffinic hydrocarbons and/or rich in isobutene.

A distillation apparatus is capable of regenerating spent NMP from an on-site process for lithium ion battery electrodes. The distillation apparatus has a raw material tank, a side-cut distillation column, and a product tank. The distillation column has a top portion where a liquid to be treated is separated into a high-concentration NMP and water containing light-boiling components, a bottom portion where refluxed liquid in the distillation column is further distilled to separate the refluxed liquid into a high-purity NMP and the high-concentration NMP containing high-boiling components, and a mid-stage portion from which the high-purity NMP is withdrawn as side-cut vapor. The distillation column has, at a rear stage, a condenser for condensing the high-purity NMP withdrawn as the side-cut vapor, and a flow controller for regulating an amount of a liquid of the high-purity NMP withdrawn from the condenser to the product tank.

An apparatus and process doubles the number of trays in a single fractionation column. A dividing wall is used to isolate a first side from a second side and fractionation on trays on each side is independent of the other. A transition vapor stream is ducted from a top of a first side to the bottom of the second side, and a transition liquid stream is ducted from a bottom of the second side to the top of the first side.

An apparatus for separating a feed stream into product streams. The apparatus includes an upper section, a middle section, and a lower section. The middle section has a dividing wall separating it into two portions. A liquid barrier blocks the flow of liquid from the upper section into the middle section and allows vapor to flow from the middle section to the upper section. A vapor and liquid barrier blocks both the flow of both vapor from the lower section to the middle section and the flow of liquid from the middle section to the lower section. Vapor conduits allow vapor to flow from the lower section to each of the middle portions in varying amounts. Also processes for separating a feed stream.

A process for separating or removing permanganate reducing compounds (PRC's) from a first mixture containing at least one PRC, methyl iodide, and water comprises the steps of: feeding the first mixture to a feed port of a distillation column, and distilling and separating the first mixture into an upper stream and a lower stream, wherein the distillation of the first mixture forms a second mixture at an upper position than the feed port, and the process further comprises the steps of: withdrawing the second mixture as the upper stream, and withdrawing the lower stream from a lower position than the feed port.

The present invention provides a distillation apparatus for NMP which is capable of regenerating a spent NMP recovered from a process for production of an electrode for lithium ion batteries on-site, in which the NMP can be purified in a simple and safe manner irrespective of variation in concentration of water in the raw material or throughput, and a recovery rate of the NMP can be further enhanced. The distillation apparatus for NMP according to the present invention comprises a raw material tank 41, a distillation column 1 and a product tank 42, in which the distillation column 1 is a side-cut type distillation column that comprises a top portion in which a liquid to be treated is separated into a high-concentration NMP and water comprising light-boiling components, a bottom portion in which a refluxed liquid in the distillation column is further subjected to distillation to separate the refluxed liquid into a high-purity NMP and the high-concentration NMP comprising high-boiling components, and a mid-stage portion from which the high-purity NMP is withdrawn as a side-cut vapor, and the distillation column is further provided at a rear stage thereof, with a condenser for condensing the high-purity NMP withdrawn as the side-cut vapor, and a flow control means for regulating an amount of a liquid of the high-purity NMP withdrawn from the condenser to the product tank.

By using the distillation device of the present application, energy loss occurring in a purification process of a solution including a waste stripper and a stripped photoresist resin used in a stripping process of a photoresist can be minimized and the installation cost of the distillation device can be reduced compared to the case in which dual distillation columns are used, thereby increasing the economic feasibility of a process.