The separation experiments of CH_4 and H_2 was carried out in a thermal diffusion column with and without packing.In the case of no packing added

the separation was affected by heating temperature

β（cut)

and residence time.The temperature gradient is the driving force of the thermal diffusion separation. The separation degree was increased with increasing of heating temperature

and it was affected by βsharply.Under the conditions of higher heating temperature

the optimum separation was obtained with the β value which was close to the mole fraction of hydrogen in the feed.The separation degree was also affected by the residence time.In the case of packing column

the separation degree was higher for the packing with larger size.However

it was still lower than the no packing one.It was greatly improved by using mesh type packing.