A group led by Japanese trading house Itochu Corp. is nearing an agreement to buy green ammonia from Hive Hydrogen South Africa, a $5.9 billion project that could make the country a global leader in producing the fuel. Hive Hydrogen may start output of green ammonia — which could be utilized as a fuel for heavy industry and power plants and is also used in fertilizer and cleaning products — from the new facility in South Africa’s southern port of Coega in 2029.