Shares in Johnson Matthey (LON:JMAT) revved up after the catalytic converter maker said its business was holding up despite the Volkswagen scandal.
The stock drove ahead 207p, or 8.4%, to 2664p as Johnson said its emission control technologies (ECT) arm had boosted sales by 8% and underlying operating profit by 16%.
Johnson also pleased investors by increasing the interim dividend by 5% to 19.5p and issuing a special dividend of 150p, totalling £305mln after selling businesses.
The group said tighter legislation known as Euro 6b to control emissions of oxides of nitrogen (NOx) in diesel cars had fuelled strong growth in Europe.
The VW controversy, which involving manipulating diesel-powered car emission systems to allow them to pass emission tests, has sparked speculation about future demand for diesel cars in Europe.
While not naming VW, Johnson said there had been "renewed focus on vehicle emissions, particularly since mid-September" and it continued to monitor developments closely.
The current share of diesel cars in Western Europe is 51% and Johnson expects this to trend down with fuel efficiency improvements in gasoline engines.
But John Meyer at broker SP Angel said: "Euro 6b should help to counter some of this decline as it deals with NOx emissions and has CO2 advantages."
Johnson also said it had faced challenging conditions in its process technology (PT) and precious metal product (PMP) businesses.
Performance in platinum group metal (PGM) refining and recycling took a hit from a decline of over 20% in average PGM prices, hitting PMP operating profit by 25%.
In PT, oil and gas catalyst sales were ahead but the downturn in upstream oil and gas markets due to falling oil prices affected its diagnostic services arm.
Chief executive Robert MacLeod said: "Despite the current environment of low platinum group metal and oil prices, and the more muted outlook in the chemicals markets that we supply, we expect the underlying performance of the group's continuing businesses in 2015/16 to be similar to 2014/15.
"The full year outlook for the group is in line with current market expectations."
Shares in Johnson started selling off in late spring and recently settled into a fresh two-month trading range some 30% below May highs.
Augustin Eden at Accendo Markets said: "Head winds in the form of weak platinum prices and a lacklustre outlook in chemical markets are likely to deter those in search of capital returns for the time being. A return to those May highs might be a tall order."