Anhydrous Iodine Drying for Corrosion-Free HI Production

The patent applies preliminary action by removing water from iodine before it is used in the hydrogen iodide production process. Multiple drying methods are employed: distillation to remove bulk water, followed by contact with concentrated sulfuric acid or phosphoric acid to remove residual water, and finally treatment with drying agents like calcium sulfate or molecular sieves to achieve anhydrous conditions. This preliminary water removal prevents subsequent corrosion and yield reduction while maintaining ease of handling the dried iodine throughout the process.

The patent removes water from iodine before the hydrogen iodide production process through a multi-stage drying procedure. This preliminary action prevents water from participating in side reactions or forming ternary mixtures during the chemical process, thereby maintaining high product separation efficiency and yield. The dried anhydrous iodine is then used in the reaction H2 + I2 → 2HI, ensuring optimal productivity.

The patent segments the water removal process into distinct sequential stages, each targeting a different level of water content. First, distillation removes bulk water. Second, concentrated sulfuric acid or phosphoric acid removes residual water. Third, drying agents like calcium sulfate, molecular sieves, or phosphorous pentoxide remove trace water to achieve anhydrous conditions. This segmentation allows each step to be optimized independently and enables the use of relatively simple equipment for each stage, reducing overall process complexity while achieving high manufacturing precision in water content reduction.