Hydroformylation process

An improved exothermic hydroformylation process having at least two reaction stages, comprising the following steps:

• (a) reacting hydroformylation reactants exothermically in a first reaction stage in a fluid reaction mixture to form a reaction product;
• (b) transferring a process stream of fluid reaction mixture from a reaction stage to one or more later and separate reaction stages(s) for further exothermic, product-forming reaction and then to product recovery unit operation(s);
• (c) transferring a heat transfer stream of reaction mixture from a reaction stage to an external heat exchanger where it is cooled and dividing the cooled stream into multiple cooled reaction mixture streams;
• (d) transferring a cooled reaction mixture stream from step (c) back into the same reaction stage from which it was removed to cool the reaction mixture in that reaction stage;
• (e) transferring at least one cooled reaction mixture stream(s) from step (c) into and through heat exchange means that cool a different reaction stage, and returning it to the same reaction stage from which removed;
• and
• (f) separating and recovering a reaction product from the reaction mixture and optionally recycling at least some reaction mixture components to the reaction mixture in a reaction stage.