Abstract: Producing mesophase pitch from liquid hydrocarbon feed comprising multi-ring aromatic compounds. In a first stage reactor feed is converted to isotropic pitch product contaminated with mesophase pitch. Contaminated isotropic pitch is charged to a second stage reactor where mesophase formation by self-assembly into spherical crystal clusters produces a mesophase pitch product. Water or steam added to the first stage reactor increases conversion of aromatic liquid feed, increases mesophase contamination of isotropic pitch product and reduces coke formation in the isotropic pitch reactor.
Abstract: A process for making mesophase and/or isotropic pitch. An aromatic rich liquid is charged at high temperature and pressure to a first thermal polymerization reactor to produce an isotropic pitch rich liquid which is flashed. Residual liquid is charged to a second thermal reactor to produce mesophase pitch. The reactors can be either tubular reactors or CSTRs.
Type:
Grant
Filed:
February 20, 2018
Date of Patent:
August 4, 2020
Assignee:
Advanced Carbon Products, LLC
Inventors:
Donald P Malone, David C Boyer, Thomas C Holcombe
Abstract: A process and apparatus for making isotropic pitch are disclosed. A tubular reactor operating at high velocity and pressure converts aromatic rich liquid feed to pitch within minutes. Reactor is heated by electric resistance or inductance, a salt or molten metal bath, or fired heater. Reactor effluent flashes and isotropic pitch recovered from the flash drum. Softening point is affected by flash drum pressure or stripping steam. Unconverted feed may be recycled. Process makes little gasoline, simple condensation of flash drum vapor may produce gas oil and gasoline fractions. Isotropic pitch is made in a single step with a coking value of 50 to 55 wt %. Time and temperature in the reactor convert at least 20 wt % of feed and any recycle material present to isotropic pitch. Pressure is preferably above 500 psig, to suppress mesophase formation and produce isotropic pitch with less than 0.5 wt % mesophase.