Argon Recovery Patents: Who Leads, Where the Gaps Are 2026
- One filer dominates the ranking. the leading assignee holds 93 of the records in the 13-company ranking, with a long tail down to single-digit counts by fifth place.
- Filing peaked in 2018 at 11 records and the 2021-to-2024 span shows a full -100% drop to zero, though 2025-2026 counts are still filling in under normal publication lag.
- Nearly every record sits in F25J, gas liquefaction and separation, at 99.2% of the 127 records in scope, with only thin secondary coverage in B01D separation processes and C01B inorganic compounds.
Filing growth compares 2021 (3 records) with 2024 (0) — a three-year span. 2024 is the most recent year we treat as complete: publication lags filing by roughly 18 months, so 2025 onwards are still filling in and any growth rate that ends there would understate the field.
What this landscape covers
Argon recovery in cryogenic air separation sits at the intersection of column design and gas purification: getting argon out of the nitrogen-oxygen-argon mixture without sacrificing oxygen purity or product recovery ratio. The search set here is narrow by design, pairing argon recovery and argon column air separation terms in the title against claim and description language covering argon transition zone, structured packing, column height, recovery ratio and crude argon deoxygenation. That combination surfaces 127 published records spanning 2015 through the 2026 cut-off.
The filing pattern is uneven rather than steadily rising or falling: a concentrated peak in 2018, a small leader that accounts for the bulk of the ranked assignees, and a set of individual inventor names alongside corporate entities. That mix suggests a mature but still-active niche where most of the foundational architecture was claimed some years ago and recent activity is thinner.
Let an AI agent run this analysis on your own technology
Pick a task. Every answer cites the patents behind it.
Filing trend and technology composition
Two views of the same 127-record set: how filing activity moved year over year, and which IPC subclasses the records fall into. Because a single record can carry more than one classification, the subclass shares below add up to well over 100%.
Filing activity, 2015-2026
Filing peaked at 11 records in 2018. The 2021-to-2024 window, the most recent span that can be treated as complete, shows a full -100% move down to zero; 2025 and 2026 figures are still incomplete under the usual 18-month publication lag and should not be read as a continued decline.
IPC subclass distribution
F25J (gas liquefaction and separation) covers 99.2% of the 127 records in scope, confirming this is overwhelmingly a cryogenic distillation problem rather than a chemical scrubbing one. B01D (separation processes) appears in 15.7% of records and C01B (inorganic compounds) in 5.5%, both as secondary classifications alongside the dominant F25J code.
Shares are the percentage of the 127 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Argon Recovery in Air Separation with Eureka
This page is one run against one query. Ask Eureka your own question about argon recovery in air separation and every answer comes back with the patent numbers behind it.
Try EurekaThe most-cited prior art in this set
EP0341854B1 — structured packing for oxygen and argon recovery
Argon recovery in a cryogenic air separation process is improved by using structured packing in at least the low pressure column and an argon sidearm column of an integrated multi-column, e.g. three-column, cryogenic distillation system.Assigned to Air Products and Chemicals, Inc., granted 1992-11-25. This is the same family that produced the two most-cited records in the set (EP0341854A1 and US4871382A), both centred on packed-column architecture.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | EP0341854A1 | Air separation process using packed columns for oxygen and argon recovery | 49 |
| 2 | US5313800A | Process for maximizing the recovery of argon from an air separation system at high argon recovery rates | 47 |
| 3 | US4871382A | Air separation process using packed columns for oxygen and argon recovery | 37 |
| 4 | US20190331418A1 | System and method for high recovery of nitrogen and argon from a moderate pressure cryogenic air separation u… | 34 |
| 5 | US5019144A | Cryogenic air separation system with hybrid argon column | 32 |
| 6 | US4842625A | Control method to maximize argon recovery from cryogenic air separation units | 31 |
| 7 | US5511381A | Air separation | 30 |
| 8 | US4994098A | Production of oxygen-lean argon from air | 30 |
| 9 | US20080223077A1 | Air separation method | 29 |
| 10 | US5533339A | Air separation | 26 |
Ranked by citation count within the searched corpus. Older records tend to accumulate more citations simply by being available longer, so treat this as a signal of influence on the field rather than of current commercial relevance.
Each row carries its publication number; clicking a row searches Eureka by that number.
Put your own technology through the same analysis
Eureka on the web
When you want the answer in the next five minutes.
The agent works the prompt against patents and technical literature, citing every source.
Run your analysis now →MCP server & REST API
When it has to run inside your own pipeline.
Patent search, landscape analysis and assignee resolution as MCP tools. Drop them into any agent framework, or call REST directly.
Browse MCP servers →What the numbers say
Three patterns stand out once the ranking, the trend and the classification data are read together.
One filer set the architecture, everyone else fills in around it
The leading assignee holds 93 records against a fifth-place figure of just 3 and a tenth-place figure of 1. That gap is wide enough that the foundational packed-column and sidearm-column claims are effectively owned by a single filer, with the rest of the ranking contributing narrower, later improvements.
Activity dropped sharply after the 2018 peak
Eleven records published in 2018 mark the high point of the set. By the 2021-to-2024 window, the last span with complete publication data, filings had fallen to zero, a full -100% move. That does not necessarily mean interest has stopped; it means the architecture claimed a decade ago has not been substantially re-filed since.
Almost everything is filed as gas separation, not chemistry
F25J covers 126 of the 127 records. Secondary classifications in B01D (15.7%) and C01B (5.5%) show some claims also touch general separation equipment or inorganic gas chemistry, but the field is defined almost entirely by cryogenic distillation engineering rather than sorbent or membrane chemistry.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to argon recovery in air separation, with the prior art for and against each one.
| Assignee | Co-assignee | Shared families |
|---|---|---|
| PROSSER NEIL M | LUO YANG | 8 |
| PROSSER NEIL M | STEPHENSON NEIL A | 6 |
| PROSSER NEIL M | DU HAI | 6 |
| STEPHENSON NEIL A | DU HAI | 6 |
| LUO YANG | STEPHENSON NEIL A | 4 |
| LUO YANG | DU HAI | 4 |
| Praxair Technology, Inc. | ROOKS RAYMOND EDWIN | 3 |
| Praxair Technology, Inc. | HOWARD HENRY EDWARD | 3 |
Ten co-assignee pairs appear in the set, the strongest built around Neil M Prosser paired separately with Yang Luo (8 shared records) and with Neil A Stephenson and Hai Du (6 each), pointing to a small recurring engineering team behind several related filings.
Who holds the claims, and what is left open
The ranking is short: 13 companies and named inventors account for the entire set the data endpoint returns. Momentum has gone quiet across the board in the most recent year, which is consistent with the broader 2021-to-2024 drop rather than a sign any one filer has pulled ahead recently.
Praxair Technology
Holds the largest share of the ranked assignees by a wide margin, consistent with its presence across the packed-column and structured-packing lineage that dominates the most-cited records.
Air Products and Chemicals
Owns the EP0341854 family, the single most-cited architecture in the dataset, built around structured packing in the low-pressure and argon sidearm columns of a three-column cryogenic system.
Neil Prosser and collaborators
Appears across multiple co-assignee pairings with Yang Luo, Neil Stephenson and Hai Du, suggesting a stable engineering group filing related improvements rather than a single company's in-house team.
| Assignee | Recent year | YoY |
|---|---|---|
| Praxair Technology, Inc. | 0 | — |
| Air Products and Chemicals, Inc. | 0 | — |
| PROSSER NEIL M | 0 | — |
| HOWARD HENRY EDWARD | 0 | — |
| LUO YANG | 0 | — |
| The BOC Group plc | 0 | — |
| STEPHENSON NEIL A | 0 | — |
| DU HAI | 0 | — |
Where to take this analysis
The dataset points to specific next steps depending on whether the goal is freedom-to-operate, R&D targeting, or monitoring a competitor.
Check freedom to operate against the packed-column lineage
The EP0341854 and US4871382 family carries the highest citation counts in the set and covers structured packing in both the low-pressure and argon sidearm columns. Any new column design should be checked against this family's claim scope before committing to a packing configuration.
Run a claim comparison in EurekaWatch for renewed filing after the 2021-2024 lull
The complete data shows zero filings by 2024, but 2025-2026 figures are still incomplete under normal publication lag. A fresh pull in twelve months will show whether activity has genuinely stopped or is about to resurface.
Set up monitoring in EurekaExplore the under-claimed sub-areas directly
Recovery ratio optimisation and crude argon deoxygenation appear in the search terms but not densely in the ranked claims, which is where a narrowly drafted first claim has the best chance of clearing prior art.
Explore white space in EurekaCommon questions about this landscape
Within the 13-company ranking this dataset covers, one assignee, Praxair Technology, holds 93 of the ranked records, far ahead of the fifth-place figure of 3 and the tenth-place figure of 1. Air Products and Chemicals is separately notable as the owner of the most-cited family in the set, built around structured-packing column designs. Because this ranking reflects only the records matched by this specific search, it should not be read as a complete map of every company active in cryogenic air separation.
Filing peaked at 11 records in 2018 and the last complete span, 2021 to 2024, shows a full drop to zero, a -100% change. That said, publication typically lags actual filing by around 18 months, so the 2025 and 2026 figures in this dataset are still incomplete and should not be treated as confirming a continued decline. The honest read is that the architecture had a concentrated burst of filing activity around 2018 and has been quiet since, with the very latest picture still unresolved.
EP0341854B1, assigned to Air Products and Chemicals and granted in 1992, claims the use of structured packing in at least the low-pressure column and an argon sidearm column within an integrated multi-column cryogenic distillation system, typically a three-column arrangement. It is the anchor of the most-cited family in this dataset, with related records EP0341854A1 and US4871382A also carrying high citation counts. Anyone designing a packed-column argon recovery system should review this family closely, since it underlies much of the field's later citation activity.
Based on the search terms and classification spread here, areas like recovery ratio optimisation at part-load conditions, column height reduction through packing geometry changes, and crude argon deoxygenation catalysis show up in the underlying search terms but do not carry dense recent filing activity in the ranked assignees. That pattern suggests these are worth a closer novelty check before assuming they are occupied. It does not guarantee the space is genuinely open, only that this dataset does not show heavy recent claim density there.
Extremely concentrated on one axis: F25J, gas liquefaction and separation, covers 99.2% of the 127 records in scope. Secondary classifications appear in B01D, separation processes, at 15.7%, and C01B, inorganic compounds, at 5.5%, but these are supplementary rather than dominant. This confirms argon recovery patents are drafted almost entirely as cryogenic distillation engineering rather than as chemical purification or membrane technology.
Research Argon Recovery in Air Separation in depth with Eureka
Go past this page: query the whole argon recovery in air separation corpus yourself, in your own scope.
Every answer comes back with patent numbers you can open.
Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.