This paper presents a new approach for the purification of 29% and 54% P2O5 phosphoric acid contaminated with cadmium ions using synthesized lamellar material based on manganese (Na-MnO2). The removal efficiencies of cadmium ions were 35 % and 31 % for 54% and 29% P2O5 phosphoric acid. The kinetic and isotherm studies of cadmium adsorption were performed. After the phosphoric acid purification process, Na-MnO2 material was characterized by XRD, SEM, and TGA-DTA. All the results enable the refinement of the final phase by the Rietveld method. A proposed mechanism of cadmium ion removal by Na-MnO2 was given. The stability of the material was also controlled in the acid medium 29 % and 54 % P2O5. The results confirmed that Na-MnO2 material could be a potential sorbent for the efficient removal of heavy metals from phosphoric acid solutions. This simple process can be further developed and thus opens an avenue in the industrial sector to process larger quantities using high-performance materials based on manganese. Self-consistent ab initio calculations, based on DFT (Density Functional Theory) approach and using the FLAPW method (Full potential Linear Augmented Plane Wave), were performed to investigate both the electronic and magnetic properties of materials.