Electrolyte and electrolytic purification method of waste electronic welding flux

The invention provides electrolyte which comprises methanesulfonic acid, methyl-sulfonic salt and a crystallization control agent. The main components of the electrolyte are the methanesulfonic acid and the methyl-sulfonic salt, and the concentration of lead ions and tin ions in the electrolyte is effectively increased so that the electrolyte can be used for electrolyzing under a high working current density, and the working efficiency is improved. In addition, different from a common silicofluoric acid system in the prior art, the electrolyte avoids the problem that silicon ions in the silicofluoric acid system are hydrolyzed to generate silicon dioxide precipitate and influence smooth electrolysis. Besides, the electrolyte can be used for electrolysis at the high current density, so thatthe output wastewater amount of a unit product is reduced, and the wastewater treatment capacity is reduced. Meanwhile, the electrolyte contains no harmful element fluorine, and the treatment difficulty of electrolysis waste