Reverup

FRANKFURT, June 20 (Reuters) – The private-equity owners of chemicals group Cognis have cold-shouldered a takeover offer from Lubrizol even though it was higher than that of favoured bidder BASF, sources familiar with the matter told Reuters. Lubrizol, a U.S. maker of specialty plastics and engine-oil additives, has made a bid worth about 3.2 billion euros ($4.0 billion) including assumed debt …