石油炼化工艺介绍(英文版)Environmental issues are threatening the future use of MTBE (methyl-tert-butyl ether) in
gasoline in the United States. Since the late 1990s, concerns have arisen over ground and
drinking water contamination with MTBE due to leaking of gasoline from underground
storage tanks and the exhaust from two-cycle engines. In California a number of cases of
drinking water pollution with MTBE have occurred. As a result, the elimination of MTBE
in gasoline in California was mandated, and legislation is now set to go in effect by the end
of 2003. The U.S. Senate has similar law under preparation, which would eliminate MTBE
in the 2006 to 2010 time frame.
With an MTBE phase-out imminent, U.S. refiners are faced with the challenge of
replacing the lost volume and octane value of MTBE in the gasoline pool. In addition, utilization
of idled MTBE facilities and the isobutylene feedstock result in pressing problems
of unrecovered and/or underutilized capital for the MTBE producers. Isooctane has been
identified as a cost-effective alternative to MTBE. It utilizes the same isobutylene feeds
used in MTBE production and offers excellent blending value. Furthermore, isooctane production
can be achieved in a low-cost revamp of an existing MTBE plant. However, since
isooctane is not an oxygenate, it does not replace MTBE to meet the oxygen requirement
currently in effect for reformulated gasoline.