A membrane reactor catalyst is the active material that drives a chemical reaction — such as ammonia cracking or dehydrogenation — while integrated with or adjacent to a selectively permeable membrane inside the same unit. It is patented separately from the membrane because the claim scope differs: membrane claims typically cover material composition and pore structure, while catalyst-integration claims cover how the active metal is deposited, impregnated or bonded onto or into that structure. In this dataset, catalysis-subclass filings (B01J) substantially outnumber pure separation filings (B01D), showing that the catalyst-membrane interface is where most current claim activity sits.

Filers span national research institutes, universities, oil and gas majors, and specialist membrane manufacturers, with no single entity holding a dominant share of the 208 families reviewed. Co-filing is limited, with only ten identified co-assignee pairs, meaning most patents are filed solo rather than through joint ventures. Several previously active assignees, including energy research agencies and technical universities, show no filings in the most recent year, which may reflect a shift in priority, a move to trade secret protection, or simply publication lag.

The filing trend is flat to declining over the period reviewed: activity opened at 11 filings in 2017, passed through a midpoint of 5 in 2022, and peaked at 12 in 2024 before appearing to drop toward the most recent year. Because patent publication lags actual filing by roughly 18 months, the apparent decline in 2025-2026 almost certainly understates real activity and should firm up as later filings publish. Read the multi-year plateau, not the final data point, as the more reliable signal of overall momentum.

US11090628B2, assigned to Colorado School of Mines, claims a catalytic membrane reactor built on a tubular yttria-stabilized zirconia ceramic support, with a ruthenium catalyst impregnated on the outer surface, a palladium hydrogen-permeable membrane plated over it, and cesium impregnated on the inner surface to promote ammonia conversion to hydrogen and nitrogen. It blocks that specific combination of support material, catalyst metal, membrane metal and promoter for ammonia dehydrogenation, rather than catalytic membrane reactors generally. Designs using different support ceramics, different catalyst or promoter metals, or a different membrane material would likely sit outside its literal claim scope, though a full freedom-to-operate review should check dependent claims and file history.

The clearest gaps sit in sub-areas with filing activity but comparatively thin claim density relative to the core catalyst-membrane interface: cesium-promoted ammonia-cracking supports, electrolytic membrane-catalyst co-integration overlapping with C25B, transfer of ceramic membrane designs into fuel cell architectures, and structured catalyst coatings on non-palladium membranes. These branches show enough activity to confirm commercial interest but not enough dense prior art to make new claims immediately blocked. A first claim in one of these areas would need to specify the support material, the catalyst-deposition method and the target reaction to distinguish it from the foundational ceramic-membrane art that already dominates citations.