Interbulk chief executive to step down KOERT van Wissen, the boss of chemicals transportation group Interbulk, is standing down at the end of September but will remain as a non-executive. The East Kilbride-based group, in which Clyde Blowers tycoon Jim McColl holds a stake, said logistics industry veteran Loek Kullberg will become its new chief executive on 1 October. Interbulk chairman David Rolph said van Wissen, who has been at the helm since its formation in 2006, has run the business "with great energy and leadership through some challenging economic times." In June, the firm suffered a 43 per cent slump in first-half profits to £3.8 million amid "depressed" demand across Europe. Kullberg has held senior roles at DHL and Royal Nedlloyd and was most recently a director at Dutch marine infrastructure group Royal Boskalis.