Commenting on the second quarter results, Patrick S. Williams, President and Chief Executive Officer, said,
“We continue to make significant progress in our post-COVID-19 recovery as all businesses achieved sequential and comparative quarter sales growth, and total operating income surpassed the 2019 comparative pre-COVID-19 level for the first time.
Performance Chemicals again delivered excellent results with record quarterly sales driving a 47 percent increase in operating income over the prior year. Our previously announced $10 million capacity expansion for our mild, sulfate-free technologies is on schedule for the first quarter of 2022, and we are fast tracking further capacity expansions in the US and Europe to meet growing global demand. We believe that the outlook remains strong not only in our home and personal care segments but also our growing mining, agriculture, construction and industrial end markets.
Fuel Specialties sales and operating income were very strong and above the pre-COVID-19 comparative 2019 level for the first time since the onset of the pandemic. The quarter benefited from above-average order phasing for AvGas fuel additives used in the global piston-powered general aviation fleet. The impact of these orders against expected levels was approximately $5.3 million of operating income or 16 cents of EPS for the quarter. Global distillate demand remains slightly below pre-COVID-19 levels, while global jet fuel demand is improving but still well below normalized usage. As jet fuel demand continues to recover, we expect to drive higher volumes for our additives in the coming quarters, which should improve sales mix, and be supportive to margins.
In Oilfield Services sequential sales grew by 12 percent and operating leverage again improved. We currently expect to see further increases in completions, oil production and pipeline flows over the coming quarters. All of these support continued sales and operating income growth across all of our Oilfield markets and regions. Along with our expectation for continued activity improvement in our end markets, we believe that there are several opportunities which can drive higher incremental operating margins. It is imperative that we deliver on these opportunities in the second half of 2021.
Cost inflation and supply chain constraints remain at above average levels. Price action has been taken and we plan to continue taking such action where necessary. Close communication with our suppliers and customers will remain a focus as we manage through this environment.”
Revenues in Performance Chemicals reached a record of $128.2 million, up 34 percent from $95.7 million in the second quarter last year. Volumes grew 18 percent with a positive price/mix of 9 percent and a favorable currency impact of 7 percent. Gross margins declined 1.4 percentage points from the same quarter last year to 24.6 percent. Operating income for the quarter was $17.9 million, up 47 percent from $12.2 million a year ago.
Revenues in Fuel Specialties were $143.1 million for the quarter, a 33 percent increase from $107.4 million last year. Volumes grew 20 percent with a positive price/mix of 6 percent and a favorable currency impact of 7 percent. Gross margins of 35.0 percent benefited from increased AvGas business compared to a depressed margin of 23.6 percent a year ago. Operating income for the quarter was $28.5 million, compared to $4.7 million in the same quarter last year.
Revenues in Oilfield Services for the quarter were $83.2 million, approximately doubling the $41.8 million in the second quarter last year as customer activity continued to increase. Gross margins improved by 8.3 percentage points from the same quarter last year to 32.0 percent. Operating income increased $14.6 million from the same quarter last year to $2.2 million.
Corporate costs for the quarter were $11.6 million, compared with $15.4 million a year ago, due mainly to lower personnel-related expenses.
The effective tax rate for the quarter was 44.1 percent compared to 26.2 percent last year primarily due to the enacted change in the U.K. tax rate impacting deferred tax. Excluding the effect of the rate change and other minor adjustments, the adjusted effective tax rate was 24.2 percent in line with expectations.
For the quarter, there was a net cash outflow from operating activities of $1.1 million driven by the increase in net working capital on strong sequential sales growth. In addition, the Company also distributed $14.0 million to shareholders for the semi-annual dividend. As of June 30, 2021, Innospec had $94.4 million in cash and cash equivalents, and finance lease debt of $0.2 million, resulting in a net cash position of $94.2 million.