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On Synthesis and Characterization of Sulfated Alumina–Zirconia Catalysts for Isobutene Alkylation

“…1 and Table 1 revealed that almost no changes in the pore volumes of c-Al 2 O 3 (AlS and AlCl samples) were observed after sulfation (V R = 0.69-0.70 -cm 3 /g; V mezo = 0.47-0.48 cm 3 /g; V ma = 0.22 cm 3 /g), while their specific area decreased from 195 to 154-157 m 2 /g. H OI value decreased from 8.0 to 4.8-5.0 as in fact was expected after acidic treatment with the formation of SO 4 2-and Cl -groups on the surface. Temperature-programmed desorption (TPD) of ammonia is given in Fig.…”

“…Similar results were also obtained for the sample Al-Zr-6-S (Table 1). Independent on calcination temperature, IR spectrum of the sulfated samples Al-Zr-(4)6-S exhibits peaks 1146-1152 and 1090 cm -1 related to bending vibrations of SO 4 2-ions and retains the spectral features of hydrated species (Fig. 3a) intrinsic to ZrO 2 obtained by thermal decomposition of ZrO(NO 3 ) 2 .…”

“…4, curve 3) resulted in formation of a surface structure involving SO 4 2-ions (bands at 1151-1071 cm -1 ), thermally stable H 2 O molecules (1642 and 1510 cm -1 ) and O-H groups with different coordination (absorption band at 3466 cm -1) .…”

“…Alkylation of butenes with alkanes results in high octane alkylates with a high octane number (above 94) used for both synthetic motor fuel production and for compounding of low octane number gasoline [1][2][3][4][5]. A promising direction in the development of alkylation processes is the transition from liquid-phase catalysts such as HF and H 2 SO 4 to heterogeneous catalysis thus avoiding problems related to chemical corrosion of equipment, toxicity of waste acids and their disposal.…”

“…% ZrO 2 , followed by drying at 110°C and calcination in air flow at 300°C (3), 400°C (4), 500°C (5) or 600°C (6) for 3 h. Sulfation of Al-Zr-4(6)-S and AlS-Zr-4(6) was done by impregnation of AlZr or AlS-Zr 2.0-3.0 mm sized granules with (NH 4 ) 2 SO 4 solution (corresponding to 10 wt% SO 4 2-) at 70°C. Drying and calcination was performed in the same way as for sulfated zirconia.…”