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

Table 1

Selectivity values of the different H₃PW₁₂O₄₀/SiO₂ catalysts at 𝑡 = 1000 min.

HPW loading (wt.%)	Impregnation solvent	Selectivities (%)
		C1	C2	C3	i-C4	C5	C3^=	C4^=
37.5	Acetonitrile	0.0	0.1	2.8	92.4	4.5	0.0	0.0
37.5	Acetone	0.0	0.1	1.9	94.0	3.3	0.0	0.7
37.5	Water	0.0	0.1	2.1	93.3	3.7	0.0	0.8
37.5	THF	0.0	0.1	1.6	94.4	2.8	0.0	1.1
37.5	Methanol	0.0	0.1	2.4	92.6	4.2	0.0	0.7
5.0*	Water	0.1	0.1	2.4	77.1	10.0	0.1	10.2
20.0	Water	0.0	0.0	1.7	94.9	3.1	0.0	0.2
37.5	Water	0.0	0.1	2.1	93.3	3.7	0.0	0.8
50.0	Water	0.0	0.1	2.1	93.7	3.9	0.1	0.1
75.0	Water	0.0	0.1	3.0	91.7	5.0	0.0	0.1

 *Values to be taken with care due to the very low conversion.