Method of continuously cleansing polyarylene sulfide
AssigneeKureha Corporation
InventorsMichihisa Miyahara, Norio Saitou, Mitsuhiro Matsuzaki
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Abstract
A polymerizate slurry obtained through a reaction of an alkali sulfide source and an aromatic dihalide compound in an organic polar solvent and comprising polyarylene sulfide particles, a by-produced alkali metal salt and the polar organic solvent, is continuously contacted countercurrently with a washing liquid, thereby continuously and efficiently recovering washed polyarylene sulfide particles. Furthermore, the by-produced alkali metal salt is removed, and the polar organic solvent is recovered, efficiently.
Claims12
A process for continuously washing polyarylene sulfide, comprising a washing step of subjecting a polymerizate slurry to continuous countercurrent contact with a washing liquid;
- said polymerizate slurry containing polyarylene sulfide particles, a by-produced alkali metal salt and a polar organic solvent and obtained through a reaction of an alkali sulfide source and an aromatic dihalide compound in the polar organic solvent;
- wherein the washing step includes a step of moving the polyarylene sulfide particles as an upward flow countercurrently contacting the washing liquid, and the process further includes a step of continuing the upward flow of the polyarylene sulfide particles to separate the washing liquid therefrom and recover the polyarylene sulfide particles.
A process for treating a slurry, comprising:
- subjecting a slurry comprising a dispersion liquid medium and at least two types of solid particles dispersed in the liquid medium to sequential washing steps including:
- a first washing step of washing the slurry by countercurrent contact with a first washing liquid which does not dissolve any of the solid particles but is miscible with the dispersion liquid medium, and
- a second washing step of bringing the washed at least two types of solid particles into contact with a second washing liquid which selectively dissolves a part of the at least two types of solid particles and is also miscible with the first washing liquid;
- wherein at least one of the first and second washing steps comprises a step of moving said at least two types of solid particles as an upward flow countercurrently contacting the washing liquid, and the process further includes a step of continuing the upward flow of the solid particles to separate the washing liquid therefrom the recover the solid particles.
Dependencies are inferred from the claim text.