Aenert news. Invention analysis
In our earlier articles we have addressed latest developments disclosed in recent patent documents related to Liquid Organic Hydrogen Carriers (LOHC) based on aromatic compounds (29.09.2023) and heterocyclic compounds (08.09.2023) and revised some specific aspects of these approaches. Today we will take a look at recent patent documents disclosing novel methods, equipment, and compositions used in a hydrogenation process. This process is an essential part of the LOHC technology. In hydrogenation, hydrogen is reacted with another substance, usually in the presence of a catalyst and at specific conditions, adding hydrogen atoms to a carrier molecule, thus forming a new substance, which is then used to store and transport hydrogen in this new bound form.

Patent documents were collected and analyzed for this review based on their applicability to hydrogenation phase of LOHC technology. These documents concern various aspects of hydrogenation, including process parameters, hydrogenation reactors, special catalysts and their production, integration of hydrogenation reactors with auxiliary equipment, etc. It is also worth mentioning that individual patent documents can describe hydrogenation as a part of a complex system – such documents were also included into the collection in cases when hydrogenation or its integration into the system was disclosed sufficiently to be of interest for professionals in this field.

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

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)

By the number of documents, the leading positions are taken by De Nora Permelec Ltd (JP), Yokohama National University (JP), and Chiyoda Corporation (JP).

In the pool of patent documents revised for this review, the largest patent families of those having at least one document published in the past five years, were patent families represented by the following core documents (Core document is a base document for which a complete description of the invention is available in generally-accessible patent databases): US10144004B2 (18 documents), US9522393B2 (17 documents), and US8758722B2 (16 documents):

Method for producing catalyst composition for hydrogenation and catalyst composition for hydrogenation / P: US10144004B2 / IPC: B01J31/22, B01J31/02, B01J31/06, B01J31/12, B01J31/14 / ARAKI Yoshifumi; SASAYA Eiji; NITTA Katsunori / Asahi Kasei Kogyo K.K. (JP) / Appl. date: 22.10.2013; Publ. date: 04.12.2018 / United States Patent and Trademark Office / Core document: US10144004B2 / Technology categories: OAA / Technology elements: Hhg, Hct / Problems: HCHD, LEHD, HLEC / Technical solution types: M, C / Claims: 19 / Rating: 20; the most recent documents in this family were published on 17.06.2019 (MY169932A) and 19.06.2019 (MY169989A);

A titanocene compound represented by following general formula:


Image from US10144004B2

Catalyst composition for hydrogenation and method for hydrogenation using the same / P: US9522393B2 / IPC: C08F8/04, B01J31/02, B01J31/06, B01J31/12, B01J31/14, B01J31/22, C08C19/02, C08F297/06 / ARAKI Yoshifumi; SASAYA Eiji; NITTA Katsunori / Asahi Kasei Kogyo K.K. (JP) / Appl. date: 12.09.2013; Publ. date: 20.12.2016 / United States Patent and Trademark Office / Core document: US9522393B2 / Technology categories: OAA / Technology elements: Hhg, Hct / Problems: HCHD, LEHD, HLEC / Technical solution types: M, C / Claims: 19 / Rating: 20; the most recent document in this family was published on 18.06.2019 (MY169940A);

Method for producing hydrogen aimed at storage and transportation / P: US8758722B2 / IPC: C07C5/10, C01B3/26 / Okada Yoshimi; Saito Masashi; Wakamatsu Shuhei; Shimura Mitsunori / Chiyoda Corporation (JP) / Appl. date: 24.03.2011; Publ. date: 24.06.2014 / United States Patent and Trademark Office / Core document: US8758722B2 / Technology categories: OAC / Technology elements: Hop, Hhg / Problems: EC, HCHD, LEHD / Technical solution types: M / Claims: 5 / Rating: 20; the most recent document in this family was published on 19.11.2019 (BR112012021858B1).

The following abbreviations are used hereinbefore: C - Composition; M - Method; OAA - Alkene, Alkyne; OAC - Arene/Aromatic compound; Hct - Catalyst; Hhg - Hydrogenation; Hop - H2 production by other methods; EC - Ecological problems; HCHD - High cost of hydrogenation or dehydrogenation; HLEC - High cost or low efficiency of catalyst; LEHD - Low efficiency of hydrogenation or dehydrogenation.

In the revised collection of patent documents disclosing various aspects of hydrogenation with regard to Liquid Organic Hydrogen Carriers (LOHC), the most commonly encountered problems were LEHD - Low efficiency of hydrogenation or dehydrogenation, HLEC - High cost or low efficiency of catalyst, and HCHD - High cost of hydrogenation or dehydrogenation.

In the majority of cases, technical solutions disclosed in the revised patent documents were represented in the form of methods. Although being a bit smaller, the number of documents proposing novel compositions and devices was also considerable.

Individual patented solutions of those collected for the present review were dedicated to the use of toluene as Liquid Organic Hydrogen Carrier (LOHC), which is generally considered one of the promising compounds for hydrogen transport and storage.

Mostly, these patented solutions were attributed to the following IPC indices:

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; C07C5/10 - of aromatic six-membered rings; C25B3/25 - with a cyclohexane ring; C25B9/23 - Ruthenium, rhodium, osmium or iridium; C07C13/18 - characterised by their surface properties or porosity; B01J23/46 - Reduction; C25B9/19 - Palladium; C01B3/22 - combined with noble metals; C25B15/08 - Solids; B01J35/10 - Impregnation, coating or precipitation.

More than 80% of these documents were registered in the CNIPA (CN), KIPO (KR), JPO (JP), EPO, USPTO (US), and WIPO patent offices.

In the collection of recent patent documents in which toluene is considered the main LOHC carrier compound of the invention and which describe novel hydrogenation approaches, the most noticeable groups of inventions were those aimed at solving the problems of Hydrogenation efficiency (19 documents), Excess power consumption in hydrogenation process (6 documents), and Oxygen formation on anode (5 documents).

By the Editorial Board