加压下La_2O_3/BaSO_4催化剂甲烷氧化偶联反应的研究

STUDY ON THE OXIDATIVE COUPLING OF METHANE ON La_2O_3/BaSO_4 CATALYST AT ELEVATED PRESSURE

研究了La2 O3 /BaSO4催化剂上甲烷氧化偶联反应的性能。随着压力、反应温度和O2 /CH4的增加 ,C2 选择性下降。在一定范围内增高CH4空速可以提高C2 选择性和C2 收率。在 0 .4MPa、CH4空速 80 0 0 0h 1、780℃、CH4 O2 =8 1的条件下 ,稳定运转了 5 0 0h ,C2 选择性和C2 收率分别在 6 2 .3%～ 6 4 .6 %和 11.6 %～ 12 .7%之间。

The Performance of La 2O 3/BaSO 4 catalyst has been investgated for oxidative coupling of methane (OCM) at elevated pressure. It is found that C 2 selectivity of catalyst decreases with the elevated pressure,risen temperature and increased O 2/CH 4 ratio, the best way to improve C 2 selectivity and C 2 yield of the catalyst is the proper increase of CH 4 space velocity. Under the conditions of T=780℃,P=0.4MPa,O 2/CH 4=1/8 and space velocity of CH 4:80 000h -1 ,the activity and selectivity of catalyst are kept steady with the C 2 selectivty and C 2 yield being 62.3%～64.6% and 11.6%～12.7% respectively after a 500-hour continuous test.The analysis of XRD shows that the phase composition is stable.