Research On Synthesis Of Chromium Hydroxide And Its Foundational Application

CrOOH,also known as chromium hydroxide or chromic acid,is one of the main products of chromium chemical industry,and it is also an important precursor for the production of Cr₂O₃.Because of its good thermal stability,corrosion resistance and wear resistance,it has a wide range of applications in coatings,adsorption,catalysis,and building materials.The traditional CrOOH production process is not only tedious,but also has harsh production conditions.Due to the serious product agglomeration,the specific surface area is small,which severely limits its application value in adsorption and catalysis..In this paper,the traditional process of preparing chromium hydroxide by reducing chromate under hydrothermal conditions were improved and optimized.A multi-dimensional nanostructured chromium hydroxide self-assembled by nanosheets was synthesized.And the application of chromium hydroxide in adsorption and catalysis was explored.The following achievements and innovative progresses were exhibited:?1?The effect of experimental conditions such as the pH value and additives?PVP?of the system during the hydrothermal process on the morphology of the product was systematically studied.By optimizing the experimental conditions,a multi-dimensional nanostructured chromium hydroxide self-assembled by nanosheets was stably produced,the agglomeration phenomenon was solved,and a large specific surface area product was obtained..?2?The synthesized chromium hydroxide was applied to chromate to remove vanadium.Studies have shown that an appropriate amount of chromium hydroxide can effectively remove 91.57%of the vanadium in the sodium chromate solution,chromium is rarely adsorbed,realizing effective separation of vanadium and chromium.For the saturated chromium hydroxide,a mild solvent regeneration method is used to effectively regenerate the adsorbent,and the regeneration rate reaches 92.6%,which can realize the regeneration and recycling of the adsorbent.?3?The synthesized chromium hydroxide was used to catalyze the thermal decomposition of ammonium perchlorate?AP?,The in situ DRIFTS-MS measurements was used to detect the change of surface functional groups and the products during the catalytic process,and the media effect of CO₂ on the NH₃adsorption and oxidation in the thermal decomposition of ammonium perchlorate was observed.Based on this phenomenon,we proposed a new catalytic mechanism and verified the mechanism through a series of experiments.Not only enriches the catalytic mechanism of AP but also provides a new possible direction for designing high-performance AP catalysts in the future.