Chemical reactor for use with overly reactive chemicals
A chemical reactor for use in a chemical process wherein a reactant and/or a target product is prone to produce undesirable byproducts through secondary reactions. The reactor is configured with a first flow passage for passing a flow of an overly reactive reactant; a permeable first wall for controlled flow of the overly reactive reactant into a second flow passage providing a flow of a second reactant; a permeable second wall having a catalyst supported on an inner surface thereof for catalyzing reaction of the reactants flowing in the second flow passage; the permeable second wall passing through a flow containing the target product; and a non-permeable third wall defining a third flow passage for exiting the product mixture. The reactor can be employed in selective oxidation, oxidative dehydrogenation, and alkylation processes to reduce the formation of byproducts.
1. A chemical reactor for converting two or more chemical reactants into a least one chemical product, the reactor comprising:
(a) a first flow passage fluidly connected to at least one inlet;
(b) a first permeable wall characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the first permeable wall extending along at least a portion of length of the first flow passage; the inner surface of the first permeable wall being fluidly connected to the first flow passage;
(c) a second flow passage extending along a length of the first permeable wall; the second flow passage being fluidly connected to the outer surface of the first permeable wall;
(d) a second permeable wall characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the second permeable wall extending along a length of the second flow passage; the second permeable wall supporting on its inner surface a catalyst; the inner surface of the second permeable wall including the catalyst being fluidly connected to the second flow passage;
(e) a third flow passage extending at least along a length of the second permeable wall; the third flow passage being fluidly connected to the outer surface of the second permeable wall;
(f) a non-permeable wall characterized by an inner surface and an outer surface; the non-permeable wall extending along a length of the third flow passage; the inner surface of the non-permeable wall being fluidly connected to the third flow passage; and
(g) an outlet fluidly connected to the third flow passage.
2. The reactor of claim 1 wherein the first permeable wall and second permeable wall are each independently constructed from a permeable material selected from the group consisting of permeable glass, quartz, ceramic, metal, plastic, molecular sieve, zeolite, and solid ionic conductive materials.
3. The reactor of claim 1 wherein the non-permeable wall is constructed from a non-permeable material selected from the group consisting of non-permeable glass, quartz, ceramic, metal, and plastic materials.
4. The reactor of claim 1 wherein a catalyst is provided as a coating along the inner surface of the second permeable wall.
5. The reactor of claim 1 wherein the first flow passage, the second flow passage, and the third flow passage are configured to provide for cocurrent flow.
6. The reactor of claim 1 wherein the first and third flow passages are configured to provide for cocurrent flows; while the second flow passage is configured to provide for countercurrent flow compared to the flows of the first and third flow passages.
7. The reactor of claim 1 wherein the third flow passage is sealed at an inlet side of the passage.
8. The reactor of claim 1 wherein a heat transfer structure fills the third flow passage bounded by the outer surface of the second permeable wall and the inner surface of the non-permeable wall.
9. The reactor of claim 1 wherein the reactor is constructed from a set of three concentric, cylindrical tubes, such that the first permeable wall comprises one permeable tube; wherein the second permeable wall comprises a permeable tube arranged circumferentially around the first permeable tube; and wherein the non-permeable wall comprises a third tube constructed of non-permeable material arranged circumferentially around the second permeable tube.
10. The reactor of claim 9 wherein a fourth tube comprising a non-permeable material is arranged circumferentially around the third tube.
11. The reactor of claim 10 wherein a heat transfer fluid or heat transfer structure fills the annular volume between the third and fourth tubes.
12. A macro-reactor comprising a plurality of reactors configured as in claim 1 and disposed within a single housing.
13. A chemical reactor for manufacture of a target chemical product with reduced formation of byproducts, comprising:
(a) a first flow passage fluidly connected to at least one inlet;
(b) a first permeable tube characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the first permeable tube defining at least a portion of the first flow passage; the inner surface of the first permeable tube configured in fluid communication with the first flow passage;
(c) a second permeable tube characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the second permeable tube disposed circumferentially around the first permeable tube; the second permeable tube supporting on its inner surface a catalyst;
(d) a second flow passage defined by an annular space between the outer surface of the first permeable tube and the inner surface of the second permeable tube;
(e) a non-permeable tube characterized by an inner surface and an outer surface; the non-permeable tube disposed circumferentially around the second permeable tube;
(f) a third flow passage defined by an annular space between the outer surface of the second permeable tube and the inner surface of the non-permeable tube; and
(g) an outlet fluidly connected to the third flow passage.
14. The reactor of claim 13 wherein a ratio of inner diameter of the permeable second tube to outer diameter of the permeable first tube ranges from greater than 1.1:1 to less than about 20:1.
15. The reactor of claim 13 wherein a ratio of inner diameter of the non-permeable third tube to outer diameter of the permeable second tube ranges from greater than 1.1:1 to less than 20:1.
16. The reactor of claim 13 wherein under operative conditions a ratio of concentration of reactant fed into the second flow passage relative to concentration of reactant fed into the first flow passage ranges from 50:1 to 1,000:1, measured at the catalyst surface.
17. A chemical reactor for manufacture of a target chemical product with reduced formation of byproducts, comprising:
(a) a first flow passage fluidly connected to an outlet;
(b) a first permeable wall characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the first permeable wall extending along at least a portion of length of the first flow passage; the inner surface of the first permeable wall being fluidly connected to the first flow passage; the outer surface of the first permeable wall having a catalyst supported thereon;
(c) a second flow passage extending along a length of the first permeable wall; the second flow passage being fluidly connected to the outer surface of the first permeable wall;
(d) a second permeable wall characterized by an inner surface and an outer surface and a plurality of pores extending from the inner surface to the outer surface; the second permeable wall extending along a length of the second flow passage; the inner surface of the second permeable wall being fluidly connected to the second flow passage;
(e) a third flow passage extending at least along a length of the second permeable wall; the third flow passage being fluidly connected to the outer surface of the second permeable wall;
(f) a non-permeable wall characterized by an inner surface and an outer surface; the non-permeable wall extending along a length of the third flow passage; the inner surface of the non-permeable wall being fluidly connected to the third flow passage; and
(g) an inlet fluidly connected to the third flow passage.