Preparation of a novel bentonite intercalation composite by changing the chemical state of aluminum

A new environment‐friendly bentonite intercalation composite was successfully obtained from alumina sol intercalation. This process used industrial grade pseudo boehmite as the aluminum source and provided with the advantage of zero emission of acidic wastewater. The bentonite intercalation composite was investigated by XRF, ICP, XRD, FT‐IR, BET, and pyridine‐FTIR. Results indicated that the basal spacing was enlarged from 14.72 to 15.60 Å; the specific surface area increased by 128%; and the total acid content increased from 65.32 to 245.76 μmol/g. The catalytic activity of this composite was tested by alkylation of aromatics with olefins. The results show that the weak Lewis acid generated by extra‐framework aluminum and specific surface area play a decisive role, while weak Brønsted acid site is not the active site for this alkylation reaction. A new bentonite intercalation composite was successfully obtained from alumina sol intercalation. It exhibits excellent catalytic activity in the alkylation of aromatics with olefins, because weak Lewis acid produced by extra‐framework aluminum plays a decisive role in catalyzing alkylation, while the weak Brønsted acid site is not the active site.