China is set to import a record volume of U.S. ethane this month as petrochemical producers seek alternative feedstocks for their operations after the war in the Middle East choked off crucial supplies.Shipments of U.S. ethane are expected to rise to an all-time high of 800,000 tons in April, according to Chinese consultant JLC, which would be around 60% higher than the monthly average. Some companies can switch to using ethane, helping them offset disruptions to the supply of naphtha and liquefied petroleum gas from the Middle East after the effective closure of the Strait of Hormuz.Ethane is a natural gas liquid primarily used to produce ethylene, a building block for plastics, and China depends almost entirely on the U.S. for supply. The product became a political flash point between Beijing and Washington last year after the U.S. tightened export controls during a bitter trade war.