Analysis of CO2 absorption by water-based bubble column reactors is of great importance and computational methods help understand the process and improve its efficiency. Numerical evaluation of CO2 absorption using water in a bubble column was investigated by analysis of mass transfer in the process. The results showed that the CO2 absorption in water was increased from 0 to around 0.53 L after 450 s and the rate of CO2 absorption in water was decreased from 0.28 L/min to around 0 after 450 s. Then, the obtained results from the model were used for understanding these parameters in controlled environments using machine learning methodologies. We explored the predictive accuracy of regression models to estimate the concentration of CO2 (mol/m3) across spatial (z) and temporal (t) dimensions in a controlled environment. The dataset comprises measurements collected over 451 s at varying depths, structured as a regression task to model CO2 based on t(s) and z(m). Data preprocessing involved Z-score normalization and Isolation Forest-based outlier detection, optimizing data integrity. The methodology incorporated the Whale Optimization Algorithm (WOA) to refine model hyper- parameters, enhancing performance metrics across Decision Tree (DT), K-Nearest Neighbors (KNN), and Multilayer Perceptron (MLP) models. Evaluation metrics such as R2, RMSE, and MAE indicated KNN's superior predictive capability, demonstrating strong generalization across training, cross-validation, and testing phases. The KNN model accurately captured the non-linear spatial-temporal relationships inherent in the dataset, achieving a near-perfect R2 of 0.9991 on the training set and 0.9979 on the test set, with low RMSE (0.291) and MAE (0.042) values on the test data. These results underscore the model's high precision in predicting concentration levels across varying depths and time, supporting its potential for applications requiring precise concentration estimations in similar contexts.