The compact dimensions and large surface area-to-volume ratio characteristic of microchannel geometries can efficiently utilise endothermic and exothermic chemical reactions to enhance heat transfer, control temperature, adjust reactivity, intensify processes and develop innovative thermal management techniques. Becasue of this, the exothermic and endothermic chemical reaction mechanism is explored by considering the titanium oxide (TiO2) nanoparticles with water (H2O) as the base fluid. An incompressible Newtonian fluid flows through the porous microchannel. The pressure gradient factor assumes the flow in the microchannel. Energy and solutal transportation analyses are made with Robin’s boundary conditions and activated energy phenomena. Similar variables are introduced to convert the model into non-dimensional. A numerical scheme, namely the Runge–Kutta-Fehlberg 45th (RKF-45) scheme, is implemented to execute solutions. The results explore that thermal distribution decreases for elevated activation energy values and Biot number values in the exothermic case while enhanced in the endothermic case. The rate of thermal distribution declines with the addition of solid fractions and chemical reaction parameters in the endothermic case; the opposite trend is observed in the exothermic case.