_____________________________________________________________________________________________________ *Corresponding author: E-mail: nwobasiveronica@yahoo.com; Asian Journal of Chemical Sciences 12(1): 21-44, 2022; Article no.AJOCS.87836 ISSN: 2456-7795 Empirical Modelling and Optimization of Ngbo Pillarred Activated Clay Catalysts using Response Surface Methodology V. N. Nwobasi a* , Philomena K. Igbokwe b and Akindele O. Okewale c a Department of Food Science and Tech, EBSU, Abakaliki, Nigeria. b Department of Chemical Engineering, UNIZIK, Awka, Nigeria. c Department of Chemical Engineering, Federal University of Petroleum Resourses, Effurun, Delta State, Nigeria. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/AJOCS/2022/v12i119137 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/87836 Received 26 March 2022 Accepted 01 June 2022 Published 08 July 2022 ABSTRACT In this work, Box-Behnken”s Response Surface Methodology (RSM) was applied to study the esterification reaction effectiveness of Ngbo pillarred activated clay catalyst. The esterification was monitored based on temperature, time duration, amount of reactant, catalyst weight, and particle size. The Box--Behnken’s Response Surface Methodology indicates that the pillarred clay-catalyzed esterification reactions proceed through dual Acid-complex and Alcohol-complex mechanisms, with the Alcohol mechanism dominating. The esterification efficiencies of acetic acid and ethanol by acid- activated Ngbo clay catalyst optimized using RSM models indicated the estimated esterification percentage of ˃99%. The predicted and experimental values under the same conditions showed less than 5% difference, making the Box-Behnken design approach an efficient, effective, and reliable method for the esterification of acetic acid with ethanol. The produced catalyst was optimized using A-One way ANOVA modelling, which indicated the correlation coefficient of the regression of 0.8674, implying that 86.74% of the total variation in the esterification reaction was attributed to the experimental variables. The result obtained indicated that the process could be applied in the esterification of acetic acid to avoid the drawbacks of corrosion, loss of catalyst and environmental problems. Original Research Article