𝑛-Butane Isomerization over Silica-Supported Heteropolyacids: Study of Some Parameters

Table 2

Initial and steady-state conversion and deactivation rate for the different silica-supported polyoxometalates.

Polyacid	Solvent	Loading (wt.%)	Initial conversion (%)	Steady-state conversion (%)	Deactivation rate (min)
	Methanol		11.5	3.4	145
H3PW12O40	Water*	37.5	10.9	2.6	165
			14.2	3.3	130
	Acetonitrile		4.9	2.3	195
	Acetone		3.1	2.2	25
	THF		0.5	1.2	—
		5	0.3	0.1	65
		20	5.2	1.6	35
H3PW12O40	Acetonitrile	37.5	4.9	2.3	195
		50	6.9	2.5	250
		75	7.2	3.6	330
H3PW12O40			10.9	2.6	165
	Water	37.5	14.2	3.3	130
H4SiW12O40			20.0	5.1	140

 *Two different preparations of the catalyst.