Effect of Coexistent Hydrogen on the Selective Production of Ethane by Dehydrogenative Methane Coupling through Dielectric-Barrier Discharge under Ordinary Pressure at an Ambient Temperature

Table 1

Effect of coexistent gases on the carbon selectivity, in comparison with the other methods of dehydrogenative methane coupling.

Method	Coexistent gas	Ratio (v/v)	Power (w)	Product carbon selectivity (mol%)
				C2H6	C2H4	C2H2	C3H8	(CH3)2CHCH3	n-C4H10	others
DBD	None	0	3	46.9	16.1	5.6	19.1	6.6	3.6	2.0
			24	49.8	5.1	3.9	21.7	5.2	5.4	8.9
			44	50.4	3.6	3.1	21.5	5.1	5.9	10.4
	H2	0.3	3	45.8	8.7	9.2	12.0	3.3	4.7	16.3
			24	53.0	2.6	3.8	19.9	4.6	6.7	9.4
			44	51.1	2.2	3.1	20.3	4.9	6.8	11.6
		0.88	3	63.3	0.0	4.1	20.3	5.6	6.7	0.0
			24	67.1	0.0	0.8	19.1	4.4	4.4	4.1
			44	69.4	0.0	0.7	19.0	3.9	4.1	3.0
	He	0.3	3	47.2	11.5	6.6	17.9	4.5	5.3	7.0
			24	47.5	4.1	3.5	22.1	5.4	6.6	10.8
			44	48.0	3.2	5.7	22.2	6.6	1.1	13.2
		0.88	3	50.1	9.7	4.0	22.7	4.8	6.0	2.8
			24	50.7	6.4	2.7	24.7	4.6	6.8	4.1
			44	50.4	5.4	2.0	24.3	4.7	8.9	5.4
MW^a Plasma [16]	None	0	10	25.5	31.9	41.9	0.3	—	—	0.3
			30	10.7	21.4	66.5	0.3	—	—	1.0
			50	2.4	6.3	90.2	0.2	—	—	0.9
			100	1.2	4.2	92.9	0.3	—	—	0.3
			150	0.6	2.9	95.1	0.3	—	—	1.0
			200	0.5	2.5	95.9	0.2	—	—	0.9
			250	0.4	2.4	95.2	0.2	—	—	0.8
			300	0.2	2.2	84.8	0.3	—	—	12.6
TDCR^b [5]	None	0	1220 K^c	39.2	60.8	—	—	—	—	—
			1300 K^c	19.1	63.9	10.1	6.9	—	—	—
			1400 K^c	1.2	65.4	31.1	2.3	—	—	—

^aMicrowave, ^bthermal diffusion column reactor, ^csurface temperature of Pt-loaded carbon rod.