Aenert news. Invention analysis
In our previous articles we already got acquainted with recent patenting trends in such aspects of Liquid Organic Hydrogen Carriers (LOHC) technology as aromatic LOHC compounds (29.09.2023), heterocyclic LOHC compounds (08.09.2023), hydrogenation (17.10.2023), and dehydrogenation (30.10.2023). In this article we will revise the use of catalysts in major phases of LOHC technology. Catalysts play a crucial role in both hydrogenation and dehydrogenation phases. In the processes the catalysts are used to increase the reaction speed and efficiency, improve storage capacity or quality of the product, and adjust other parameters. However, catalysts also may add complications to the hydrogen storage and transport process. For instance, usually, the most efficient catalysts are noble metals such as Platinum, Palladium, Iridium, and others, which are very expensive materials. Less costly catalytic materials may require specific process parameters or exhibit lower activity values. Recently patented technical solutions in the field of liquid organic hydrogen carrier hydrogenation and dehydrogenation catalysts are aimed at solving these and other similar problems.

Below we provide a brief review of recent inventions disclosing the use of catalysts in Liquid Organic Hydrogen Carriers technologies. The patents selected for this review are considered applicable to the field of LOHC catalysts based on the presence of description of catalytic materials (active materials or catalyst support) in the claims. However, in individual cases the inventions may additionally disclose other aspects of LOHC system, such as hydrogenation or dehydrogenation process parameters or equipment, etc.

Below is a list of the top applicants by their patenting share in the field of LOHC catalysis.

Applicants share in the intellectual property market, %. Patents, 2019-2023



Value: Market involvement ratio*; Y axis: Ownership ratio; Bubble size: Volume ratio.
*(Market involvement ratio = volume ratio multiplied by ownership ratio, where Volume ratio - share of applicant documents in total number of documents, Ownership ratio - applicant's participation share in total number of documents)

In the revised set of documents, Sinopec China Petroleum & Chemical Corporation (CN) and its affiliated organizations, Chiyoda Corporation (JP), and AIST National Institute of Advanced Industrial Science and Technology (JP) are leading by the number of patents obtained in the past five years.

The largest patent family in the pool of documents collected for the present analysis of those having at least one document published in the past five years includes 31 patent documents and is represented by core document AU2020269473A1 (Core document is a base document for which a complete description of the invention is available in generally-accessible patent databases). It is followed by patent families with core documents WO2020224584A1 (14 patent documents) and US10745628B2 (13 documents):

Organic hydrogen storage raw material dehydrogenation catalyst, carrier of the catalyst, hydrogen storage alloy, and method for providing high-purity hydrogen / A: AU2020269473A1 / IPC: C22C19/03, C01B3/56, C22C14/00, C22C23/06, C22C30/00 / Lin Wei; Yang Xue; Song Haitao; et al. / Sinopec RIPP Research Institute of Petroleum Processing (CN); Sinopec China Petroleum & Chemical Corporation (CN) / Appl. date: 06.05.2020; Publ. date: 12.11.2020 / IP Australia / Core document: AU2020269473A1 / Technology categories: OAC, OHC / Technology elements: Hdh, Hct / Problems: EC, HCHD, LEHD / Technical solution types: M, C / Claims: 16 / Rating: 13; the most recent documents in this family were published on 15.11.2022 (CN111892016B) and 21.10.2022 (CN111893360B);

有机储氢原料脱氢催化剂以及该催化剂的载体、储氢合金、和提供高纯度氢气的方法 / en: Catalyst for dehydrogenating organic hydrogen storage raw material, carrier for catalyst, hydrogen storage alloy, and method for providing high purity hydrogen / A: WO2020224584A1 / IPC: B01J23/26 / Lin Wei; Yang Xue; Song Haitao; Sun Min / Sinopec China Petroleum & Chemical Corporation (CN); Sinopec RIPP Research Institute of Petroleum Processing (CN) / Appl. date: 06.05.2020; Publ. date: 12.11.2020 / World Intellectual Property Organization / Core document: WO2020224584A1 / Technology categories: OAC, OHC, OAN / Technology elements: Hdh, Hct / Problems: LEHD / Technical solution types: M, C / Claims: 14 / Rating: 10; the most recent documents in this family were published on 21.10.2022 (CN111892018B) and 15.07.2022 (CN111895266B);

Hydrogenation catalyst for aromatic hydrocarbon and hydrotreatment method using the catalyst / P: US10745628B2 / IPC: C10G45/48, B01J21/04, B01J21/06, B01J23/755, B01J35/10, B01J37/02, B01J37/18, C01F7/02, C01F7/34, C01G23/04, C01G23/08, C01G53/04, C07C5/10, C07C13/18, G01N23/20 / Imagawa Kenichi; Kobayashi Haruto; Muto Akihiro; Inoue Shinichi / Chiyoda Corporation (JP) / Appl. date: 09.09.2017; Publ. date: 18.08.2020 / United States Patent and Trademark Office / Core document: US10745628B2 / Technology categories: OAC / Technology elements: Hhg, Hct / Problems: HLEC / Technical solution types: M, C / Claims: 4 / Rating: 20; the most recent documents in this family were published on 06.06.2021 (SA517390005B1) and 06.04.2021 (CA2979801C).

The following abbreviations are used in the documents hereinbefore and hereinafter: C - Composition; M - Method; OAC - Arene/Aromatic compound; OHC - Heterocyclic; OAN - Amine; Hct - Catalyst; Hdh - Dehydrogenation; Hhg - Hydrogenation; LEHD - Low efficiency of hydrogenation or dehydrogenation; EC - Ecological problems; HCHD - High cost of hydrogenation or dehydrogenation; HLEC - High cost or low efficiency of catalyst.

The most commonly-encountered problems in the collection of recent patents disclosing various catalysts used in Liquid Organic Hydrogen Carriers (LOHC) are High cost or low efficiency of catalyst, Low efficiency of hydrogenation or dehydrogenation, and High cost of hydrogenation or dehydrogenation.

The majority of technical solutions provided in the inventions under revision are represented in the form of compositions, although the number of documents disclosing methods is only slightly smaller. The number of inventions disclosing devices though can be considered negligible.

In the list of active catalytic materials used in the inventions, rare-earth metals hold a prominent place. Below we provide a brief statistical review of such inventions describing LOHC catalysts that contain rare-earth metals as the active material alone, as an option, or in combination with other elements.

In the majority of cases, the following IPC indices were assigned to these inventions:

According to the International Patent Classification, the IPC indices above have the following definitions: C01B3/00 - Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen; B01J23/89 - combined with noble metals; B01J23/46 - Ruthenium, rhodium, osmium or iridium; C22C30/00 - Alloys containing less than 50% by weight of each constituent; B01J23/42 - Platinum; B01J35/10 - characterised by their surface properties or porosity; C01B3/26 - using catalysts; C01B3/56 - by contacting with solids; Regeneration of used solids; C22C1/02 - by melting; B01J23/44 - Palladium.

CNIPA (CN) is a strong leader by the number of patents granted for such inventions (about 90%), followed by the KIPO (KR) and USPTO (US) patent offices.

Further, we analyzed the collection of recent patents describing various catalysts for LOHC hydrogenation and dehydrogenation containing rare-earth metals with regards to the specific problems they are aimed at solving. The most popular problems in these documents were Process efficiency in general (13 patents), H2 purity (9 patents), and Low H2 pressure (8 patents).

By the Editorial Board