NOVELTY - A microreactor has at least two interconnected and parallel paths micromachined in a substrate of silicon or other micromachinable material. The paths are parallel, serpentine paths extending from an inlet to an outlet to promote equal residence time of fluids flowing across the paths. The microreactor has a filter for trapping catalyst particles proximate to the outlet of the reactor.    USE - For use in the production of hydrogen for fuel cells.    ADVANTAGE - The microreactor can produce hydrogen as required for up to 25 Watt fuel cell.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a method of catalyst loading of a microreactor, comprising preparing a fluid-based suspension of catalyst particles of a desired particle size range; introducing the suspension into one of the inlet of the reactor or a catalyst introduction port communicating with the channels under pressure while drawing a vacuum at the outlet of the reactor; and continuing introduction until the channels are packed with catalyst;    (2) a method for producing hydrogen by reaction of methanol and water vapor in the presence of a catalyst, comprising loading the channels of a microreactor with a low temperature shift/methanol reforming catalyst; heating the reactor to 195-275degreesC; introducing methanol and water vapor into an inlet of the reactor; and withdrawing a hydrogen rich product stream from an outlet of the microreactor;    (3) a method of making the microreactor comprising etching an annular region in a substrate to form the radial flow reaction chamber; forming a filter for trapping catalyst particles near the inner and outer circular boundaries of the reaction chamber, e.g. by etching parallel grooves in the substrate where the grooves are of a width less than catalyst particle diameter; and flowing a fluid (gas/liquid)-based suspension of catalyst particles through the annular chamber to form a packed bed of the catalyst;    (4) a method of bonding a capillary tube of polytetrafluoroethylene or other thermoplastically deformable material to a passage in a glass wafer comprising treating the capillary tube surface to render it wettable to an epoxy resin, inserting a support into the tube to prevent deformation in processing steps, inserting the capillary inside a port in the wafer, heating the capillary end near the bottom of the port to melt the tube, moving the tube to temporarily seal the tube to the port wall and introducing epoxy resin around the tube to bond the capillary to the wafer; and    (5) preparing a catalyst bed in a microreactor used to react methanol and water vapor comprising preheating the bed to 150 degreesC, reacting the methanol water feed mixture in the bed as it is heated from 150 degreesC to 175 degreesC and continuing the reaction until the catalyst bed is activated.    DESCRIPTION OF DRAWING(S) - The figure is a schematic representation of the test housing for a microreformer.    Channels (14)    Ridges (36, 38)    Pads (43, 45)