Micro-mesopore analysis of Cu2+ and Ag+ containing Al-pillared bentonite

Abstract Copper impregnated Cu@Al-PILCs, silver impregnated Ag@Al-PILCs and copper aluminum mixed Cu/Al-PILCs were prepared using a bentonite sample from the Hancili region, Turkey. Incorporation of the Cu 2+ or Ag + ions forming CuO and Ag 2 O after calcination at 573 K decreased the basal spacing of 1.85 nm for Al-PILC by approximately 0.35 nm. The specific BET surface area and mesopore + micropore volumes measured by 77 K nitrogen adsorption after calcination at 573 K decreased from 236 m 2 g − 1 and 0.174 cm 3 g − 1 to 174 m 2 g − 1 and 0.172 cm 3 g − 1 by Cu 2+ impregnation and 171 m 2 g − 1 and 0.168 cm 3 g − 1 by Ag + impregnation, while the values for Cu/Al-PILC were 209 m 2 g − 1 and 0.184 cm 3 g − 1 . The micropore volume of all samples was about 20% of the total pore volume. The average Barrett–Joyner–Halenda (BJH) mesopore and Horvath–Kawazoe (HK) micropore dimensions were within 3.5–3.9 nm and 0.44–0.48 nm, respectively. Structural properties estimated from the Dubinin–Radushkevich (DR) method by using the nitrogen adsorption data were higher than those derived from the carbon dioxide adsorption data. SEM images indicated that Cu 2+ incorporation increased the mesopore volume of the Al-PILC.