Beijing: An industrial demonstration project approved in Beijing on Tuesday has shown that hydrogen sulfide, a highly poisonous industrial waste gas, can be safely converted into high-purity hydrogen and sulfur, offering a new solution for cleaner operations in industries such as natural gas, petrochemicals and coal processing, reports Hydrogen Central.
The project can treat up to 100,000 cubic metres of hydrogen sulfide each year. It was developed by a team led by Li Can from the Dalian Institute of Chemical Physics under the Chinese Academy of Sciences. The process uses an off-field electrical method to fully break down hydrogen sulfide into hydrogen and sulfur.
Partners in the project include Shandong Sunway Chemical Group Co. Ltd., the Yulin Institute of Clean Energy Innovation of the Chinese Academy of Sciences, and Haoming Energy Technology (Dalian) Co., Ltd.
Hydrogen sulfide remains a serious challenge for the global energy sector, which continues to depend heavily on natural gas, oil and coal. The gas is extremely toxic and can easily turn into sulfur dioxide, which contributes to acid rain, environmental damage and serious health problems.
The gas is mainly produced as a byproduct of natural gas extraction, oil refining and coal use. According to the China Sulphuric Acid Industry Association, more than 8 billion cubic metres of hydrogen sulfide are handled each year in China, while the global volume exceeds 70 billion cubic metres. Worldwide reserves are estimated to be more than 4 trillion cubic metres.
Because of its widespread presence and harmful nature, completely removing and reusing hydrogen sulfide has long been a major challenge.
Research on this technology began in 2003, when Li Can’s team started studying alternative ways, including the use of light and electricity, to break down hydrogen sulfide. The team developed a system in which hydrogen and sulfur are produced in reactors separate from the electrodes, solving key issues related to large-scale use and improving safety.
The researchers later worked with coal chemical companies to move the technology from the laboratory to industrial application. The off-field electrical method allows hydrogen sulfide to be fully split into hydrogen and sulfur on a large scale.
The demonstration facility uses hydrogen sulfide produced by a methanol plant operated by Sino-Singapore Chemical, part of Henan Energy Chemical Group Co., Ltd. Operating data shows that more than 99.999 per cent of the hydrogen sulfide is converted, and both the hydrogen and sulfur produced meet high commercial quality standards.
The technology offers a new way to completely eliminate hydrogen sulfide while turning it into useful products, providing both environmental and economic benefits. Researchers estimate that if all hydrogen sulfide processed annually in China were treated using this method with wind and solar power, it could produce around 730,000 tonnes of low-carbon hydrogen each year.
