Source: Sharecast
Reported revenues at the chemicals and specialist technologies firm fell 14% in the six months to September end to £5.6bn.
Stripping out disposals, sales fell by 5%, or by 3% on a constant currency basis, to £1.2bn.
Underlying operating profits fell 4% to £154m.
Liam Condon, chief executive, said: "We delivered a resilient performance, in line with our expectations, and have continue to executive on our strategy in the first half, against a challenging macroeconomic backdrop.
"Our performance was supported by our transformation programme, which is progressing well.
"For the full year we are maintaining guidance with our confidence in the second half underpinned by further transformation benefits."
The stock fell sharply as trading got underway, however, losing 6% to 1,405p by 0830 GMT.
The FTSE 250 manufacturer of catalytic converters first announced plans to overhaul the business in 2022.
As well as selling off its non-core "value" businesses, it has cut jobs and shut plants as it refocuses on the global energy transition through its core precious metals and catalysing technologies units.