2. Methods
The microchannel reactor comprises a plurality of process microchannels
containing the catalyst, transferring heat from the process
microchannels to a heat exchanger, and removing the product from the
microchannel reactor. The heat exchanger comprises a plurality of heat
exchange channels adjacent to the process microchannels. The heat
exchange channels are microchannels. The unstructured mesh of the
microchannel reactor is illustrated schematically in Figure 1 in which
the reactor comprises a plurality of process microchannels transferring
heat from the process microchannels to a heat exchanger. The term
microchannel refers to a channel having at least one internal dimension
of height or width of up to about 2.0 millimeters. The microchannel has
a diameter of 0.7 millimeters and length of 50.0 millimeters. The other
dimension of height or width may be of any dimension. Fluid flows
through the microchannel along the length of the microchannel. The
process microchannel has an entrance and an exit and at least one heat
exchange zone adjacent to the process microchannel. The heat exchange
zone comprises a plurality of heat exchange channels, and the heat
exchange channels extend lengthwise at right angles relative to the
lengthwise direction of the process microchannel. The length of the heat
exchange zone is less than the length of the process microchannel. The
width of the process microchannel at or near the process microchannel
exit is greater than the width of the process microchannel at or near
the process microchannel entrance.