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Solvent extraction of hydrocarbons with n-methyl-2-pyrrolidone

US 3,451,925 A · Inventors: NIXON JOHN I et al.

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

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  • Granted June 24, 1969. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by June 24, 1986.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMarch 13, 1967
GrantedJune 24, 1969
Term endedJune 24, 1986
Application number—
Classification (CPC)C10G21/00
Length5 pages

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Full published documentText and every drawing sheet as a PDF.USPTOFile historyStatus, office actions, notices, fee records and petitions.USPTO Patent CenterPatent Public Search recordSearchable full text and bibliographic data.USPTO

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