SK Hynix's M16 DRAM chip plant in Icheon, Gyeonggi Province, South Korea. SK Materials Airplus, wholly owned by the group’s holding company SK Inc., decided to sell a factory that supplies industrial gas to the chip plant (Courtesy of SK Hynix) South Korean conglomerate SK Group’s industrial gas-making unit is set to sell a local production facility for about 1 trillion won ($809 million) to invest in new businesses such as advanced materials.SK Materials Airplus Inc., wholly owned by the group’s investment and holding company SK Inc., decided to unload a factory that supplies industrial gas to SK Hynix’s DRAM chip plant in Icheon, Gyeonggi Province, through pipelines, said investment banking industry sources on Tuesday.The producer of industrial and medical gas narrowed bidders for the facility to three candidates - KKR, Brookfield and Macquarie, according to the sources.SK Materials Airplus is expected to sell an industrial gas production facility in Cheongju, about 110 kilometers southeast of Seoul for about 500 billion won, industry sources said. The facility also supplies industrial gas to SK Hynix Inc. through special trailers.The company aims to use the proceeds from sales of those assets for new businesses including advanced materials with plans only to receive gas produced by the facilities without owning its own factories.Last year, SK Materials Airplus sold another facility in the Icheon complex to a local company at 58 billion won.STABLE BUSINESSThe company decomposes oxygen, nitrogen and argon through air separation devices and delivers them to customers. Its industrial gas is essential for the manufacturing processes of the semiconductor, display and solar cell industries. The recent growth in the global semiconductor raised industrial gas demand.SK Materials Airplus has been generating stable sales as its key customers are group affiliates such as SK Hynix, SK Energy and SKC, although the industrial gas market is often volatile in line with business conditions of other industries such as semiconductors and displays.SK Materials Airplus is recognized for strong competitiveness with its own plant design technology even as it is regarded as a relative latecomer in the industry.The company, formerly known as SKC Air Gas, was established as a joint venture between SKC and Japan’s Taiyo Nippon Sanso Corp. in 2007. The JV became a wholly-owned subsidiary of SK Materials that bought SKC’s stake in 2016 and Taiyo’s shares in 2018. Last year, SK Inc. last year took over SK Materials Holdings, which owns SK Materials Airplus.By Si-Eun Parkseeker@hankyung.comJongwoo Cheon edited this article.