Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification

Introduced: January 1980

Last revised: January 2026

Full Title

Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen; Reversible storage of hydrogen > Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification

Classification Context

Section:: CHEMISTRY; METALLURGY
Class:: INORGANIC CHEMISTRY
Subclass:: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF

Filing statistics

IPC C01B 3/5 belongs to the parent subclass C01B, which recorded 251,225 patent applications worldwide between 2013 and 2023. Annual filings grew from 17,923 in 2013 to 29,649 in 2023 (+65%). The most active applicants in class C01 are CHINESE ACADEMY OF SCIENCES (5,794 applications), SINOPEC (CHINA PETROCHEMICAL CORPORATION) (3,286 applications) and LG CHEM (2,689 applications).

Source: EPO PATSTAT, worldwide filings

5 direct subcodes

Child Classifications

Navigate with arrow keys, Enter to open

C01B 3/501 by diffusion
C01B 3/506 at low temperatures
C01B 3/508 by using hydrogen storage media
C01B 3/52 by contacting with liquids; Regeneration of used liquids
C01B 3/56 by contacting with solids; Regeneration of used solids

Top Applicants

Top 10 applicants by patent filingsfor class C01, 2013–2023, worldwide · Source: EPO PATSTAT

CHINESE ACADEMY OF SCIENCES 5,794
SINOPEC (CHINA PETROCHEMICAL CORPORATION) 3,286
LG CHEM KR 2,689
BASF (BADISCHE ANILIN & SODA FABRIK) DE 1,669
CENTRAL SOUTH UNIVERSITY 1,531
KMUST (KUNMING UNIVERSITY OF SCIENCE AND TECHNOLOGY) 1,252
SUMITOMO METAL MINING COMPANY JP 1,073
ZHEJIANG UNIVERSITY 1,061
PANASONIC INTELLECTUAL PROPERTY JP 1,058
PANASONIC INTELLECTUAL PROPERTY 1,038