Study on the Catalytic Activity of Bentonite-Carbon Nanodot Composite

Abstract:

Solid acid catalysts offer several advantages over liquid acids, primarily in terms of environmental friendliness, ease of separation, and reusability. They have enhanced selectivity and catalytic activity. They are particularly useful in industrial processes where corrosive liquid acids pose handling and waste disposal challenges. Potential solid acid catalysts can be prepared by the modification of naturally occurring clay samples like kaolinite, bentonite, etc. A new, economically and environmentally benign solid acid catalyst for the esterification of cyclohexanol with glacial acetic acid has been prepared from bentonite by mixing with carbon nanodots (CND) prepared from different sources. The carbon sources used for the preparation of CND are glucose, watermelon peel, lemon peel and sucrose. The samples were characterized by acidity measurements and X-ray diffraction (XRD). The XRD pattern of the sample showed that both the components (carbon nanodots and bentonite) are present in the Clay-CND composite. Clay-CND composites showed greater acidity and activity than the pure clay sample. The results showed that the greater the amount of carbon nanodots in the clay-CND composite greater the activity and acidity. Acidity and catalytic activity are correlated. The sample B-SCND, in which CND was prepared from sucrose, showed maximum percentage conversion and acidity.

• Periodical: Applied Mechanics and Materials (Volume 933)
• Pages: 11-18
• DOI: https://doi.org/10.4028/p-sJXSC1
• Online since: February 2026
• Authors: P. Pushpaletha*, M. S. Sruthi
• Keywords: Acid Catalyst, Bentonite, Carbon Nanodots, Clay-CND Composite, Esterification

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