Mitigating the removal of microplastics from water systems is a major environmental concern that requires creative solutions. A possible method to address this problem is to use magnetic nanoparticles. Here we have proposed a mathematical model to examines the effects of nanoparticle volume (Vm), magnetization (M), and distance between the nanoparticles and the magnet (r) on the effectiveness of microplastic removal. The model is numerically solved for a range of parameters enabling a thorough investigation of the system in various scenarios. Our findings are displayed as graphs enable us for in-depth examination. We show that a higher level of magnetization increases the magnetic force applied to nanoparticles. This results in a more effective attraction and capture of microplastics. Similar to this, closer spacing between the nanoparticles and the magnet increases the magnetic force, which improves the removal of microplastics. Moreover, an increase in nanoparticle volume results in a bigger adsorption surface area which raises adsorption capabilities and improves removal efficiency.