Shanghai Petroleum Exchange (SPEX) added three petrochemicals - styrene, toluene and diglycol - to its spots trading on Thursday.

Information from SPEX said that a total of 18,226 tons of styrene, toluene and diglycol, with a combined value of 180 million yuan (about 22.5 million US dollars), changed hands on the first day of trading.

The closing price for toluene was up 0.12 percent from the opening price, but the closing price for diglycol was down 3.9 percent and styrene was down 0.02 percent, reported the SPEX.

The exchange also saw 42,600 tons of fuel oil being traded on the futures market on Thursday.

Zhang Jinquan, head of research and development with SPEX, said they had made plenty of preparations for Thursday's petrochemical trading launch. He also disclosed that they would add liquefied petroleum gas (LPG) to the list when conditions were suitable.

So far, 250 companies have signed up with the SPEX to trade petrochemicals.

Styrene is a clear, colorless liquid that is produced from benzene and ethylene and is the primary raw material for styrenic polymers. Toluene is a colorless flammable liquid, which is obtained from coal tar or petroleum and used in aviation fuel and other high-octane fuels, in dyestuffs, explosives, and as a solvent for gums and lacquers. Diglycol is a kind of industrial solvent.