Patent · US Expired

Method and filtration apparatus for purifying solvents

US4889642A · kind A · utility

3Cited by
17References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 4, 1988
Grant dateDec 26, 1989
Priority date
Expiry dateAug 4, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D29/84
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method and filtration apparatus for purifying solvents. Impurities present in the solvent are separated out in the filtration apparatus via filtration using at least one filter, through which the solvent flows and upon which the impurities settle as a filter cake. At least prior to the removal of the impurities that form the filter cake from the filtration apparatus, solvent residues present in the filter cake and possibly also in the filter are recovered by evaporation. The solvent residues in the filtration apparatus are vaporized by the action of a hot, gaseous medium that is conveyed first through the filter and only then through the filter cake, i.e. the impurities, in the direction opposite to the direction in which the solvent flowed through the filtration apparatus during the filtration process.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.