This study focuses on gaining fundamental insights into the sparsely explored area of reacting multiphase flows in a compact heat exchanger. Chevron plate heat exchangers have been demonstrated to possess superior thermal performance, scalability, and mixing capability compared to more traditional shell-in-tube heat exchangers or stirred tank batch reactors. This study explores the hydrodynamic behavior of gas-evolving reacting flows in chevron plate heat exchangers. Experimental characterization of a plate heat exchanger/chemical reactor (in multi-phase flow configuration) utilizing high-speed video and axial pressure measurements was conducted. Existing correlations that were developed using air-water flow in PHEs predicted with acceptable accuracy the total pressure drop in the HEX reactor. (C) 2013 Elsevier Ltd. All rights reserved.