Patent ID: 11878953
Assignee: UNIVERSITY OF MARYLAND, COLLEGE PARK
Field: Chemical engineering (Chemistry)
Classification: CPC C  B | IPC B  C

Claim 0:
1. A methane conversion system comprising:
a first membrane reactor comprising a first gas flow volume, a second gas flow volume, and a first membrane separating the first gas flow volume from the second gas flow volume, the first gas flow volume having a first catalyst therein;
a first gas supply coupled to the second gas flow volume and constructed to provide a first sweep gas to the second gas flow volume, the first sweep gas comprising O2 or an oxygen-containing compound;
an aromatics separation device connected to receive a first processed stream from the first gas flow volume;
a second membrane reactor comprising a third gas flow volume, a fourth gas flow volume, and a second membrane separating the third gas flow volume from the fourth gas flow volume, the third gas flow volume having a second catalyst therein;
a second gas supply coupled to the fourth gas flow volume and constructed to provide a second sweep gas to the fourth gas flow volume, the second sweep gas comprising O2 or an oxygen-containing compound; and
a recycle line comprising one or more fluid conduits, the first gas flow volume of the first membrane reactor being connected to receive a recycle stream from the third gas flow volume of the second membrane reactor via the recycle line,
wherein the first reactor is constructed to convert at least some CH4 in an input gas flow stream provided to the first gas flow volume of the first reactor, so as to provide a first processed stream and such that a quantity of CH4 in the first processed stream is less than that in the input gas flow stream, the first processed stream comprising CH4, C2 hydrocarbons, and aromatics,
the C2 hydrocarbons are acetylene (C2H2), ethylene (C2H4), ethane (C2H6), or any combination of the foregoing,
the aromatics are benzene (C6H6), toluene (C7H8), naphthalene (C10H8), or any combination of the foregoing,
the first membrane is constructed such that at least some H2 is removed from the first gas flow volume by hydrogen ions permeating through the first membrane into the second gas flow volume and such that oxygen ions permeate through the first membrane from the second gas flow volume into the first gas flow volume so as to reduce coking of the first membrane,
the first reactor is constructed for autothermal operation via an exothermic reaction between the permeated hydrogen in the second gas flow volume and the O2 or oxygen-containing compound in the second gas flow volume,
the aromatics separation device is constructed to remove at least some aromatics from the received first processed stream, so as to provide a second processed stream comprising CH4 and C2 hydrocarbons, and to provide a first output stream comprising the removed at least some aromatics, a quantity of the aromatics in the second processed stream being less than in the first processed stream,
the second reactor is constructed to convert at least some CH4 in the second processed stream provided to the third gas flow volume of the second reactor, so as to provide a recycle stream to the recycle line and such that a quantity of CH4 in the recycle stream is less than in the second processed stream, the second processed stream comprising C2 hydrocarbons and aromatics,
the second membrane is constructed such that at least some H2 is removed from the third gas flow volume by hydrogen ions permeating through the second membrane into the fourth gas flow volume and such that oxygen ions permeate through the second membrane from the fourth gas flow volume into the third gas flow volume so as to reduce coking of the second membrane, and
the second reactor is constructed for autothermal operation via an exothermic reaction between the permeated hydrogen in the fourth gas flow volume and the O2 or oxygen-containing compound in the fourth gas flow volume.