During the quarter, we successfully raised our MDI selling prices, which, combined with stable benzene costs, had the effect of increasing our contribution margins. Recently, benzene costs have spiked in the U.S., primarily as a result of regional supply dislocation. We believe this will rebalance in the near term and pricing will moderate, but it will be a slight headwind in the third quarter. Overall, the margin expansion we enjoyed in the second quarter will be sustained in the second half of 2012 as utilization rates continue to tighten. Propylene oxide and our coproduct MTBE continue to perform very well, primarily as a result of an attractive spread between premium gasoline and lower-priced raw materials. Earnings for this product were in line with the previous year and decreased approximately $40 million compared to the first quarter when industry supply outages led to exceptional margins. In July, we suffered an unplanned outage at our PO/MTBE facility due to a lightning strike. This facility is back up and running now, but the repairs and lost production will have an approximate EBITDA impact of $10 million in the third quarter.
Let's turn to Slide #4. In the second quarter, our Performance Products division earned $85 million of adjusted EBITDA. During the second quarter, we experienced an unplanned outage at our ethylene oxide unit, which reduced our EBITDA by approximately $5 million. We have elected to delay our previously announced third quarter planned maintenance on this unit until the first quarter of next year to coincide with our planned polyolefins cracker maintenance. Although the second quarter contribution margins for some of our amines was low, we expect an improvement in the third quarter as the lower cost of ethylene and propylene work their way through the value chain of these products. Further, the lower cost of benzene should benefit our maleic anhyride business. We are encouraged by early demand trends within the business as order patterns have been strong thus far. As a result of the planned maintenance postponement, we expect third quarter earnings to be slightly higher than the second.