Main product process line：

       The main products are divided into the following categories according to the technical route: first, high-temperature solid-state reaction process; second, melting and casting process; third, vacuum distillation purification process。

The explanation is as follows:

   High temperature solid state reaction process

      Introduction of high temperature solid state reaction process

      High-temperature solid-state synthesis is at high temperature, solid interface through contact, reaction, nucleation, crystal growth reaction to generate a large number of compounds. High-temperature solid-state method is a common method in industrial production because of its simple preparation process, good filling, low cost and high yield. The reaction raw material is accurately weighed according to different molar ratios, mixed and loaded into a carbon-coated quartz tube. According to the different properties of reaction materials, different reaction temperature is controlled。

The main products of high temperature solid state synthesis include copper(I) iodide, indium triselenide and bismuth telluride. Taking the preparation of indium triselenide as an example，The process is as follows：

     High temperature solid state reaction process flow diagram

      Process steps of solid-state synthesis of indium selenide at high temperature

      High temperature solid state reaction production process diagram

     Fig. 1(a) schematic diagram of carbon-coated quartz tube and liquid oxygen sintering; (B) real picture of carbon-coated quartz tube after feeding; (c) schematic and physical picture of rotatable high temperature reactor; (D) high temperature reactor with different angle adjustment。

      The high-purity polycrystalline indium selenide was synthesized by high-temperature solid-state direct batch synthesis under vacuum treatment. The results of SEM, XRD, TG/DTA and ICP analysis show that: ① polycrystalline indium selenide material has high purity and complete crystal structure；②The temperature gradient during the cooling process condenses a small amount of high vapor pressure volatiles possibly remaining in the raw material at the cold end of the quartz tube, thus realizing the self-purification of the production process and ensuring the high quality of the indium selenide。 

  Melting and casting process

      brief introduction to smelting casting process

      The melting-casting method is suitable for preparing high purity and high density target material, and the process is simple, which can be described as three steps: raw material melting, casting ingot, ingot processing. The main product of smelting casting method is high purity alloy ingot, taking In-Bi-Sn polycrystalline ingot as an example, the specific process parameters are as follows：

      Smelting, casting, process flow diagram

      Schematic diagram of smelting casting process

      Fig. 2(a) ball milling schematic diagram; (b) melting casting furnace and its melting mechanism schematic diagram; (c) prepared polycrystalline rod physical diagram (surface bright showing specular reflection) ; (d) ingot slice schematic diagram; (E) the polished and polished target; (F) the finished target after binding the copper back plate。

      The results show that the ingot has the advantages of accurate composition control, good uniformity, low impurity content and high density. It is hopeful to be used as a new sputtering target material for phase change storage thin films. Compared with the phase change storage target prepared by the Powder metallurgy-hot pressing vacuum method, the melting and casting process is simple, efficient, and the production cost is low, many In-Bi-Sn targets can be obtained in batches by slicing and polishing。

    Vacuum distillation purification process

      Brief introduction of selenium purification by vacuum distillation

      On the basis of atmospheric distillation process, the company combined with vacuum treatment technology, so that the purification process does not introduce other chemicals, and greatly reduce the distillation temperature, high purification efficiency, low production costs, green environmental protection. The technology of purifying selenium by vacuum distillation has the advantages of simple structure, good sealing and convenient operation. Further improve the purity of selenium at the same time, increase the comprehensive recovery and raw material utilization。

     vacuum distillation process to purify selenium process flow diagram

      The technological process of selenium was put forward by vacuum distillation

      Schematic diagram of selenium production process by vacuum distillation

      The production technology of selenium purification by vacuum distillation is a clean, high-efficiency and low-cost technology. Compared with other methods, the invention has the advantages of simple equipment, short process flow, low energy consumption, environmental friendliness, etc. , it is of great significance to reduce the production cost, increase the production of high purity selenium and other recovery capacity。