抄録
Zr-pillared clays with different pillar density are prepared from Ni2+ exchanged clays by heat treatment in the range 160-400°C and subsequent exchange with Zr-polycations. These materials are characterized by XRD, FTIR, TGA and sorptometric techniques. Migration of Ni2+ ions from interlayer position to vacant octahedral sties in clay structure is inferred from FTIR analysis. The Zr-pillared clays with different pillar densities are used as catalysts for alkylation of phenol with methanol. Pillared materials with lesser pillar density are found to be more selective towards anisole which is attributed to the control of acidic properties. Al-pillared clays are studied as supports for PdCu bimetallic particles. Well dispersed nanometer size metallic particles are observed in pillared clay matrix by TEM analysis. EDAX analysis indicates a homogeneous distribution of metallic components in the clay and pillared clay surfaces. Nitrate ion reduction carried out over these samples reveals that the bimetallic catalysts are more active and selective to the product N2 compared to monometallic particles. Pillared clays as supports are found to be beneficial in terms of greater dispersion and higher catalytic activity compared to parent clays.
