Diamond preparation device and diamond preparation method thereof

The diamond preparation device comprises a closed electrolytic bath, an anode chamber and a cathode chamber are arranged in the electrolytic bath, a graphite electrode is arranged in the anode chamber, and an exhaust pipe and a discharge pipe are communicated with the anode chamber; a cathode bar is arranged in the cathode chamber, and a hanging basket is arranged on the cathode bar; a blow-down pipe and an argon inlet pipe are connected with the cathode chamber; a pipe ring with air holes is also arranged in the electrolytic tank; a gas guide pipe which extends out of the electrolytic tank and is provided with a second flow meter is connected with the pipe ring; the air guide pipe is connected with the blow-down pipe through a circulating pipe, and a circulating pump, a first flow tester and a heat exchanger are sequentially arranged on the circulating pipe; a feeding unit and a heating unit are arranged on the electrolytic bath; and a cooling system is arranged outside the electrolytic bath. According to th