A new way of creating hydrogen, which eliminates direct CO₂ emissions at source, has been developed by an international team of scientists.
The process reacts hydrogen-rich and sustainably sourced bioethanol taken from agricultural waste with water at just 270°C using a new bimetallic catalyst.
Unlike traditional methods, which operate between 400-600°C, are energy-intensive and generate large amounts of CO₂, the catalyst shifts the chemical reaction to create hydrogen without releasing carbon dioxide as a biproduct.
Instead, the process co-produces high-value acetic acid, an organic liquid used in food preservation, household cleaning products, manufacturing and medicine, and has an annual global consumption exceeding 15 million tons.
The researchers from Peking University and Cardiff University, say the study represents a boost in de-fossilising the chemical industry, by replacing fossil feedstocks used in making chemicals with an alternative carbon source.
Their findings, published in Science, mark a step-change in carbon-neutral hydrogen production, and establish a circular economy model for co-producing hydrogen and high-value chemicals from biomass.
Co-author Graham Hutchings, Regius Professor of Chemistry at Cardiff University, said: "Finding sustainable ways of creating the products we need for everyday life and to meet net zero ambitions for the future is a key challenge facing the chemical industry."
Hydrogen is widely regarded as one way of achieving these ambitions because it is made from natural gas. However, it is extremely energy intensive and, of course, when created through traditional methods, it produces large amounts of carbon dioxide limiting its environmental benefits. Our study offers a new pathway which allows for high-yield hydrogen production without the CO2 emissions.
According to the International Energy Agency (IEA), approximately 96% of global hydrogen production still relies on fossil fuels, emitting 9-12 tons of CO₂ per ton of hydrogen.
The team's breakthrough builds on more than a decade of collaborative research experience on metal-carbide catalysts for hydrogen production by the international group.
Lead author Professor Ding Ma of Peking University, said: "This innovative catalytic technology holds considerable promise for advancing the green hydrogen economy and supporting global carbon neutrality goals."
Furthermore, the co-generation of acetic acid, a chemical with substantial industrial applications, enhances the technology's economic viability and sustainability.
Professor Hutchings, who last year chaired a policy briefing for the Royal Society on defossilising the chemical industry , added: "By co-creating the two chemicals in tandem, the innovation could serve as a low-carbon alternative for industries such as acetate fibre manufacturing and pharmaceutical intermediates going forward."
Their paper, 'Thermal catalytic reforming for hydrogen production with zero CO₂ emission' is published in the journal Science.
