venturi has long been considered by the industry for its high efficiency and low initial cost, and has found a significant place in the removal of gas and solids in the gas phase of various industrial units. Therefore, considering the increasing importance of global warming and the effective role of Venturi scrubber in the removal of gaseous pollutants, this thesis examines the experimental effect of Fe 3 O 4 magnetic nanoparticle on the removal of CO 2 gas in a venturi with field and without magnetic fields. In this regard, the effect of four parameters of gas velocity, liquid flow rate,volumetric nanoparticles concentration and CO 2 input into the system and the effect of four levels on the removal percentage were investigated. The results indicate a positive effect of the magnetic field and magnetic Fe 3 O 4 nanoparticles‌ in the presence of a magnetic field and the use of magnetic nanoparticles. In the same conditions, the removal of carbon dioxide from inlet air reached 17.5%, while it was eliminated 8.6% for water and no magnetic field. On the other hand, the pressure drop in the venturi scrubber in the presence of a magnetic field in similar conditions ranged from 50 Pa to 200 Pa, due to the change in the distribution of droplets and further turbulence, and as a result of the more uniformity‌ of droplets in the venturi scrubber can be interpreted. The change in the distribution of droplets is probably due to the creation of a new mechanism for the better separation of droplets in the presence of a magnetic field According to the experimental results, increasing gas velocity and nanoparticle volume in the presence of magnetic field and increasing the gas flow rate and liquid flow, without magnetic field, respectively, have the largest share in the removal percentage.