Ray Machado of Air Products described monolith catalyst reactor systems, a new approach to gas liquid catalysis (particularly hydrogenations) being commercialised jointly with Johnson Matthey, know as Monolith Loop Reactors.  This technology uses monolith catalysts, which are solid catalysts with fixed catalyst structures containing parallel channels, essentially a collection of micro-scale reactors.  The system can be fitted to existing reactors.  Liquid reaction mixture is drawn from the bottom of the reactor and pumped up to a mixing zone where hydrogen gas is introduced and then the gas liquid is passed through the monolith catalyst and then back in to the top of the reactor.  The big advantage of these catalysts is that gas / liquid / solid mixing is very intimate (Taylor flow conditions) and gives extremely good mass transfer leading to greatly improved reaction rates.