The metal made {HEAD ~ Raschig rings} used as an auxiliary packing material in the present invention has {TAIL ~ a bulk volume} of preferably 0.3 3.5 times that of the shaped catalyst and a packed density of preferably 0.5 1.5 kg/l 
has
The metal made { HEAD ~ Raschig rings } used as an auxiliary packing material in the present invention has { TAIL ~ a bulk volume } of preferably 0.3 3.5 times that of the shaped catalyst and a packed density of preferably 0.5 1.5 kg / l
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH