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US 9,809,767 B2Granted
NOx removal method
AssigneeExxonMobil Chemical Patents Inc.
InventorsLarry L. Iaccino, Michael Moran, Silvio Carrettin
Life of this patent
Estimating the term…
Abstract
The invention relates to mixtures comprising molecular hydrogen, hydrocarbons, and nitrogen oxides; to processes for removing at least a portion of the nitrogen oxides therefrom; to equipment useful in such processes; and to the use of such hydrocarbons for, e.g., chemical manufacturing.
Claims24
A separation process, comprising:
- (a) providing a first stream, the first stream comprising ≧1.0 wt. % methane, ≧1.0 wt. % molecular hydrogen, and ≧2.0 ppbw of NOx, the weight percents being based on the weight of the first stream;
- (b) producing an upgraded first stream by exposing the first stream during a first time interval to a first removal agent to remove ≧50.0 wt. % of the first stream's NOx, based on the weight of the stream's NOx, wherein the first stream contacts the first removal agent at a space velocity (GHSV)≧2.5×104 hr−1, and wherein the upgraded first stream comprises <3 ppbw of NOx;
- (c) during a second time interval following the first time interval at least partially regenerating the first removal agent;
- (d) exposing the upgraded first stream to a temperature sufficient to condense at least a portion of the first stream's methane;
- (e) conducting away a second stream, the second stream comprising at least a portion of the condensed methane;
- and
- (f) conducting away a third stream, the third stream comprising at least a portion of the upgraded first stream's molecular hydrogen.
4 more elements
A hydrocarbon upgrading process, comprising:
- (a) providing a first stream comprising ≧10.0 wt. % methane, ≧1.0 wt. % of molecular hydrogen, ≧2.0 ppbw of NOx, the weight percents being based on the weight of the first stream, and ≧0.05 mole % of water per mole of the first stream;
- and
- (b) during a first time interval exposing the first stream to (i) a second removal agent to remove ≧50.0 wt. % of the first stream's water based on the weight of the first stream's water and (ii) to a first removal agent to remove ≧50.0 wt. % of the first stream's NOx based on the weight of the mixture's NOx to produce a first upgraded mixture, wherein the first stream contacts the first removal agent at a space velocity (GHSV)≧2.5×104 hr−1, and wherein the upgraded first stream comprises <3 ppbw of NOx.
A process for separating a methane-rich stream and a molecular hydrogen-rich stream from a first stream, the process comprising:
- (a) providing the first stream, the first stream comprising ≧10.0 wt. % methane, ≧1.0 wt. % molecular hydrogen, and ≧2.0 ppbw of NOx, the weight percents being based on the weight of the first stream, and ≧0.05 mole % of water per mole of the first stream;
- (b) producing a first upgraded stream by exposing at least a first portion of the first stream during a first time interval to (i) a second removal agent to remove ≧50.0 wt. % of the first stream's water, based on the weight of the first stream's water, and (ii) a first removal agent to remove ≧50.0 wt. % of the first stream's NOx, based on the weight of the stream's NOx, wherein the first stream contacts the first removal agent at a space velocity (GHSV)≧2.5×104 hr−1, and wherein the upgraded first mixture comprises <3 ppbw of NOx;
- (c) at least partially regenerating the first and second removal agents during a second time interval following the first time interval;
- (d) conducting at least a portion of the first upgraded stream to a cold box, the cold box being operated under conditions sufficient to condense at least a portion of the first upgraded stream's methane;
- (e) removing a second stream from the cold box, the second stream being the methane-rich stream which comprises at least a portion of the condensed methane;
- and
- (f) removing a third stream from the cold box, the third stream being the molecular hydrogen-rich stream which comprises at least a portion of the first upgraded stream's molecular hydrogen.
4 more elements
Dependencies are inferred from the claim text.