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The electrolytic refining of crude tin is generally carried out in the fluorosilicic acid (H₂SiF₆) system with the assistance of bone glue and β-naphthol. However, the high saturated vapor pressure and low stability of H₂SiF₆ present environmental concerns and do not align with sustainable development goals. In this paper, the electrochemical behavior of tin on a glassy carbon (GC) electrode was studied in a relatively green and environmentally friendly methanesulfonic acid (MSA) system. Bone glue, sodium lignosulfonate, and β-naphthol were used as additives to make the deposit morphology smooth and to ensure grain refinement. The electrochemical reduction process of Sn²⁺ in an MSA system is a quasi-reversible process controlled by diffusion. The apparent activation energy <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>E</mi></mrow><mrow><mi>a</mi></mrow></msub></mrow></semantics></math></inline-formula> = 14.189 kJ/mol for the ion diffusion of Sn²⁺ was further calculated. The results of chronoamperometry showed that the electrocrystallization of Sn²⁺ on the GC electrode gradually tended to three-dimensional instantaneous nucleation with the increase in applied potential. The morphology and phase of the deposits were analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the deposits were uniform and dense pure tin. This work elucidates the electrochemical behavior of tin in a methanesulfonic acid system.