Patent · US Expired

Processes for the manufacture of enriched pitches and carbon fibers

US4996037A · kind A · utility

10Cited by
7References
20Claims
0Family size

Inventors

Key dates

Filing dateMar 12, 1986
Grant dateFeb 26, 1991
Priority date
Expiry dateMar 12, 2006

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD01F9/155
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

There are provided improved processes for the manufacture of enriched pitches, carbon fiber precursors, carbon fibers, and graphite fibers. The improvement comprises employing an elevated wiped-film evaporator in a wiped-film evaporator system comprising the wiped-film evaporator and a means for recovering enriched pitch, such as a positive displacement pump, to form an enriched pitch from catalytic pitch and regulating the operating conditions of the wiped-film evaporator system to provide the desired enriched pitch. The wiped-film evaporator is located a specific distance above the means for recovering enriched pitch. The vertical distance between the outlet of the wiped-film evaporator and the inlet of the means for recovering enriched pitch is within the range of about 10 feet to about 40 feet, preferably about 20 feet to about 40 feet.

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