Device and method for preparing magnesium hydroxide, hydrogen gas and chlorine gas through magnesium chloride solution

The invention provides a device and method for preparing magnesium hydroxide, hydrogen gas and chlorine gas through magnesium chloride solution. The device comprises an electrolytic cell, anode electrodes and cathode electrodes. Anode electrode plates of the anode electrodes and anode working surfaces are parallel and fixed together through connecting plates. Cathode electrode plates of the cathode electrodes and cathode working surfaces are parallel and fixed together through connecting plates. The bottoms of cathode chambers are communicated with the electrolytic cell. The method comprises the steps that 1, the magnesium chloride solution is injected into the electrolytic cell and anode chambers; 2, the anode electrodes and the cathode electrodes are powered on to conduct electrolysis, and the current density is controlled within 0.01-0.20A/cm ; 3, chlorine gas and hydrogen gas produced through electrolysis are collected; 4, new magnesium chloride solution is supplemented; and 5, generated Mg(OH)2 is deposited or concentrated on the cathode electrode working surfaces, and Mg(OH)2 is scraped off through a scraping plate. The method has the advantages that the electrolytic efficiency is high, the product purity is high, and the production cost is low; the device is simple in structure, convenient to operate and suitable for large-scale industrial production.