UPDATE 1-Huntsman CEO grilled on suit to stop deal

* CEO had no knowledge of any bank involvement in suit

* Banks' attorney tries to distance banks from deal

* CEO defends 2008 financial projections (Recasts with additional testimony)

By Anna Driver

CONROE, Texas June 17 (Reuters) - Huntsman Corp's (HUN.N) chief executive testified on Wednesday that he had no knowledge the investment banks his company is suing had anything to do with a lawsuit that played a role in the collapse of a $6.5 billion buyout of Huntsman in 2008.

An attorney for Credit Suisse Group AG (CSGN.VX) and Deutsche Bank AG (DBKGn.DE) used his cross-examination of the executive to try to distance the banks from the deal and paint the buyers as the entities that caused Huntsman the most harm.

Huntsman is suing Credit Suisse and Deutsche Bank for more than $4.6 billion in damages. The banks had agreed to finance the buyout, announced in July 2007, by Hexion Specialty Chemicals Inc, owned by private equity firm Apollo Management LP [APOLO.UL].

Apollo and the banks later backed out of the deal, claiming it would create an insolvent company as the U.S. economy slowed.

The buyout's implosion was triggered when Apollo issued a news release on June 18, 2008 that questioned the chemical company's solvency. Hexion and Apollo also filed a lawsuit to stop the deal the same day.