Apparatus and process method for preparing simple substance arsenic by continuously reducing arsenic oxide

Abstract

The invention relates to an apparatus and a process method for preparing simple substance arsenic by continuously reducing arsenic oxide. The apparatus comprises an arsenic oxide negative pressure feeding system, a reducing bin, a continuous unloading system, a reducing furnace and a product discharging device. The above systems are connected according to a production flow. The process is a method for preparing the simple substance arsenic by continuously reducing arsenic oxide based on the above apparatus. The apparatus is simple in structure, convenient for use and operations and short in preparation flow, and can prepare a great amount of the simple substance arsenic by continuous reduction rapidly and effectively. The apparatus for continuously reducing high pure arsenic oxide by once heating without cooling effectively overcomes the problems in intermittent arsenic oxide reduction by repeated heating and cooling.

Description

technical field [0001] The invention relates to a process and equipment for preparing elemental arsenic by reducing oxides with hydrogen, in particular to a process and equipment for obtaining elemental arsenic by reducing arsenic oxide. Background technique [0002] In the preparation of high-purity elemental arsenic, whether it is ultra-purity arsenic oxide obtained by vacuum distillation purification or high-purity arsenic oxide obtained by atmospheric distillation purification, hydrogen reduction of high-purity arsenic oxide is required to obtain high-purity elemental arsenic; arsenic oxide Because it is solid powder or glassy solid particles, it has no fluidity, and its reduction is to put high-purity arsenic oxide into a tubular quartz boat or titanium boat, and then put the boat with the material into the tubular quartz boat. Reduction is carried out in the reaction tube, and only 8~20kg of arsenic oxide can be put in each boat. The disadvantages are as follows: [0...

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Problems solved by technology

[0003] 1. Due to the intermittent reduction of 8~20kg at a time, it is difficult to control the balance between the temperature and the vaporization rate of arsenic oxide in the boat part of the reduction furnace. When the temperature is high, the vaporization amount of arsenic oxide is large, and the required hydrogen suddenly increases, and the hydrogen supply is insufficient. Tail water collector The hydrogen backflow participates in the reaction, and negative pressure is formed in the reaction tube to suck in air, which poses serious safety hazards;

[0004] 2. Due to the difficulty in balancing the temperature and the vaporization rate of arsenic oxide, the yield of arsenic oxide reduction is unstable. The yield can reach 50-60% if the operator is experienced, and only 30-50% if the operator is unskilled. Far lower than the theoretical 75%, seriously affecting the reduction effic