<![CDATA[The esterification of acetic acid with ethanol to produce ethyl acetate is an important reaction widely applied in the chemical, pharmaceutical, and food industries. However, this process often results in low conversion when performed without an efficient catalyst, as the reaction is reversible and limited by equilibrium. Therefore, developing a stable and active heterogeneous catalyst is essential to enhance the reaction rate and product yield. This study aims to improve the catalytic performance of natural zeolite through modification with cobalt chloride (CoCl₂) using the wet impregnation method to introduce additional active sites and strengthen surface acidity. The modified cobalt-zeolite catalyst was evaluated in the esterification of acetic acid and ethanol at a temperature of 70 °C under various catalyst loadings ranging from 0,25 to 2 grams and reaction times from 15 to 120 minutes. The catalytic performance was analyzed based on acetic acid conversion obtained from titration analysis. The results showed that cobalt impregnation significantly increased catalytic activity compared to both pure and acid-activated zeolites. The optimum condition was achieved using 1 gram of catalyst with a reaction time of 30 minutes, yielding a maximum acetic acid conversion of 92.24 percent. The enhancement in activity is attributed to the formation of new Lewis acid sites and the increased surface acidity caused by cobalt incorporation into the zeolite framework, which facilitates stronger interactions between the catalyst and reactant molecules. The cobalt-modified zeolite exhibited higher structural stability and superior catalytic efficiency, demonstrating that cobalt acts not only as an active site but also as a structural and acidity modifier. In conclusion, cobalt-modified natural zeolite shows great potential as an effective heterogeneous catalyst for ethyl acetate synthesis. Future work is recommended to investigate the reusability, regeneration capability, and long-term stability of the catalyst for continuous and industrial-scale esterification applications.]]>
