Engelhard Corp. said it would vigorously oppose...

Engelhard Corp. said it would vigorously oppose any attempt by the Justice Department to block the company’s plan to acquire Filtrol, a Vernon-based manufacturer of petroleum refining catalysts. The Justice Department contends that the acquisition by Engelhard, of Edison, N.J., would have an adverse impact on the competitive nature of the market for fluid catalytic cracking catalysts used by petroleum refiners to make gasoline and other products from crude oil.