BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a summary drawing showing one example of the circulation fixed-bed type reaction apparatus for use in the present invention.
FIG. 2 shows a summary drawing showing one example of a single flow fixed-bed type reaction apparatus for use in the present invention. In the drawing, numeral References are: 1: A tube-reactor loaded with a film type catalyst, 2: Buffering tank, 3: Liquid feeding pump, 4: Conduit pipe for feeding, 5: Conduit pipe for packed tower, 6: Packed tower, 7: Raw material tank, 8: Product tank.