Michael McMurray
Executive Vice President and Chief Financial Officer at LyondellBasell Industries
Thank you, Bob. Good morning, everyone. Please turn to slide seven, and let me begin by highlighting our strong cash generation, which has been enhanced by our recent growth investments. In the second quarter, LyondellBasell generated $1.9 billion of cash from operating activities that contributed towards the more than $4 billion over the past 12 months. Our free operating cash flow yield has been 10.1% over the past four quarters and free operating cash flow for the second quarter improved by more than 80% relative to the second quarter of 2019. We expect continued improvement of our last 12 months cash flow performance as we move forward through each quarter of 2021.
Let's turn to slide eight and review the details of our cash generation and deployment during the second quarter. As I have mentioned during previous calls, a strong and progressive dividend plays a fundamental role in our capital deployment strategy. In the second quarter, we expressed our confidence in our outlook by increasing the quarterly dividend by 7.6% to $1.13 per share. We continue to invest in maintenance and growth projects during the quarter with approximately $430 million in capital expenditures. Strong cash flow supported debt repayments of $1.3 billion, bringing our year-to-date debt reduction to $1.8 billion. We closed the second quarter with cash and liquid investments of $1.5 billion.
Last week, S&P Global Ratings recognize the improvement in our metrics by upgrading our credit ratings and indicating a stable outlook. We expect that robust cash generation and an anticipated tax refund will enable continued progress on our goal to reduce our net debt by up to $4 billion during 2021 and further strengthen our investment-grade balance sheet. One modeling item of note. Our original full year net interest expense guidance of $430 million did not include extinguishment costs associated with our accelerated debt repayment program. As a result, our 2021 net interest expense will likely exceed this prior guidance. Please turn to slide nine to review our quarterly profitability.
In the second quarter of 2021, LyondellBasell's business portfolio delivered record EBITDA of $3 billion. This was an improvement of more than $1.4 billion relative to the first quarter. Our results reflect robust demand for our products driven by the recovery in global economy and our growth investments. Markets remained tight during the second quarter as the industry returned to normal operation following first quarter disruptions from the winter storm that constrained production for LyondellBasell and nearly all of our competitors with operations in the state of Texas. Persistent consumer and industrial demand has met tight markets, leading to seven consecutive months of North American polyethylene contract price increases totaling more than $900 per ton.
We expect market conditions to remain robust and that continued progress in global reopening, sizable order backlogs in the increasing demand for transportation fuels will all support strong margins across LyondellBasell's businesses. Our previous quarterly EBITDA record set in the third quarter of 2015 was approximately $2.2 billion, with more than $140 million of EBITDA contributed by our Refining segment. Today, our growth investments are helping offset a challenging refining environment and enabling us to surpass the 2015 record. Our aim is to leverage our larger business portfolio to achieve improved results at all stages of the business cycle. Now let's review second quarter results for each of our segments. As mentioned, my discussion will describe our underlying business results, I will begin with our Olefins and Polyolefins Americas segment on slide 10. Strong demand, improved margins and our growth investments drove second quarter EBITDA to a record of $1.6 billion, $709 million higher than the first quarter. Olefins results increased by approximately $310 million compared to the first quarter due to higher margins and volumes.
LyondellBasell's cracker operating rates increased to 93% and following the first quarter Texas weather events, about five points above the second quarter industry average. Margins improved primarily due to the absence of high cost incurred during the prior quarter's weather events. Polyolefin results increased by about $400 million during the second quarter as robust demand in tight markets drove higher prices and margins for polyethylene and polypropylene. We anticipate continued strength in demand and margins for our O&P and Americas businesses during the third quarter. While consultants are predicting some margin compression for ethylene recent outages have caused prices to quickly rebound and demonstrated that markets remain relatively tight. High demand, low downstream inventories and customer backlogs are expected to continue and provide ongoing support for strong polymer margins. As of this week, our August order volumes for PE and PP in the Americas segment are stronger than any prior month in 2021. Now please turn to slide 11 to review the performance of our Olefins and Polyolefins Europe, Asia and International segment. Similar to the Americas, robust demand and improving margins in our EAI markets drove second quarter EBITDA to a record $708 million, $296 million higher than the first quarter.
Olefins results improved by $100 million as margins increased driven by higher ethylene and coproduct prices. Demand was robust during the quarter, and we operated our crackers at a rate of 96%, more than 10% above industry benchmarks. Combined polyolefin results increased approximately $180 million compared to the prior quarter. Strong polymer demand drove spread improvements with price increases for polyethylene and polypropylene outpacing monomer prices. Margin improvements were partially offset by a small decline in polyolefin volume. During the third quarter, we could see modest rebalancing of tight European markets as customers take downtime for summer holidays. Please turn to slide 12 as we take a look at our Intermediates and Derivatives segment. Robust demand expanded our margins and increased our sales volumes following the Texas weather events and some plant maintenance during the prior quarter. Second quarter EBITDA was $596 million, more than three times higher than the prior quarter. Second quarter propylene oxide and derivative results increased by $170 million driven by record high margins. Intermediate Chemicals results increased by about $170 million, primarily due to higher product prices for most of the businesses.
Oxyfuels and related products results increased by $70 million, driven by higher margins, benefiting from improved demand and higher gasoline prices. We expect continued strength in durable goods and improving transportation fuels demand to increase third quarter volumes for our I&D segment. Margins could slightly moderate if industry production rates remain strong. Please turn to slide 13 and allow me to dive a little deeper into transportation trends that support our improving outlook for LyondellBasell's oxyfuels and refined products. Demand for transportation fuels are rebounding from pandemic close. Total gasoline and distillate demand in June was within 5% of prepandemic levels.
Reduced demand in margins for refined products is mostly due to lagging demand for jet fuel associated with business and international travel. Jet fuel demand remains stubbornly below pre-pandemic levels. As vaccinations in global travel resumes through 2022 and 2023, we expect refining margins will improve and drive additional earnings power for LyondellBasell's Houston refinery. The chart on the left illustrates the Northwest Europe raw material margin for MTBE, which is an industry marker for our oxyfuels products sold into gasoline blending markets around the world. While Oxyfuels are typically a reliable performing business through the cycle, low demand for gasoline pushed this margin into breakeven or negative territory over the prior four quarters.
Since the beginning of this year, global demand for gasoline and gasoline blending components such as MTBE and ETBE has improved, increasing the margin to an average of $167 per ton during the second quarter. This is a significant rebound and well within the historical range shown by [Technical Issues] Now let's move forward and review the results of our Advanced Polymer Solutions segment on slide 14. The margin improvement was offset by a decline in volumes as semiconductor shortages reduced demand for our polymers serving automotive and electronic end markets. Second quarter EBITDA was $129 million, lower than the first quarter.
Compounding & Solutions results decreased by about $25 million as volumes decline for polymers supplied to the automotive sector appliance manufacturing and other industries that were constrained by chip shortages. Advanced Polymer results increased by approximately $10 million due to improved polymer price spreads over propylene raw materials. In July, feedstock cost for our polypropylene compounds produced in Europe have increased and are likely to pressure margins during the third quarter. We only expect gradual volume recovery for compound supply to automotive electronics applications as semiconductor supply constraints decrease over the coming quarters.
Now let's turn to slide 15 and discuss [Technical Issues] and lower prices for refinery-grade propylene co-product. This resulted in second quarter EBITDA of negative $81 million, an improvement of $29 million relative to the first quarter of 2021. In the second quarter, the Maya 2-1-1 benchmark increased by $6.14 per barrel to $21.46 per barrel. The average crude throughput at the refinery increased to 248,000 barrels per day, an operating rate of 93%. In July, we continue to see improvements in refined product demand and we are running the refinery at nearly full rates. Strong demand for diesel and improving demand for gasoline is expected to improve refining margins and could enable our refinery to return to profitability before the end of 2021. And as mentioned, full margin recovery will require a stronger rebound in jet fuel demand. Please turn to slide 16 as we review the results of our Technology segment. Increased licensing revenue was offset by a decline in Catalyst margin, resulting in a second EBITDA of $92 million, $2 million lower than the prior quarter. We expect that third quarter profitability for our technology business will be similar to the same quarter last year based on the anticipated timing of licensing revenue and catalyst demand.
With that, I'll turn the call over to Bob.