Synthesis, Characterization, and Catalytic Activity of NAPO-5 and NAPO-11

Article abstract of DOI:10.1246/bcsj.68.3659

Nickel-substituted aluminophosphate molecular sieves (NAPO-5 and NAPO-11) were synthesized hydrothermally using triethylamine and dipropylamine as templates.Structures were confirmed by X-ray powder pattern, and unit cell parameters calculated by a standard least square refinement technique.The isomorphous substitution of nickel in the aluminophosphate framework is evidenced by the considerable increase in unit cell volume compared to unsubstituted AlPO4-5 and AlPO4-11.In addition, electron spin resonance and diffuse reflectance spectra were carried out to produce supporting evidence for the isomorphous substitution of nickel.Acidity was determined by TPD-TGA method which shows two types of acid sites.Symmetry and asymmetry vibrations were obtained from infrared spectra.Chemical analysis by ICP and BET surface area are also reportedd.The physicochemical properties of the catalysts were correlated towards isomerization of camphene at various (WHSV)^-1 values and temperatures.The products formed are tricyclene and 2-bornene and the selective formation of tricyclene was achieved over, these catalysts.