barium sulphate solution

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The demand for TiO2 has been steadily increasing over the years, driven by the growth of the paint and coatings industry, as well as the expansion of its use in other applications such as electronics and cosmetics. In addition, the increasing awareness of the environmental impact of traditional production methods has led to a growing interest in more sustainable production techniques, such as the use of bio-based feedstocks or the implementation of closed-loop processes.

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The raw material used in this method is FeSO4. In order to maintain the Fe3 + concentration in the reaction medium in a specific range, reducing agent iron sheet is added in the reaction process. Iron yellow crystal seed was added and air was introduced to synthesize iron yellow under certain pH conditions. The method mainly includes two steps: (1) firstly, FeSO4 · 7H2O is used as raw material, NaOH or NH3 · H2O is used as precipitant or pH regulator, and air is used as oxidant to prepare crystal seed; (2) Iron yellow is produced by two-step oxidation with crystal seed, FeSO4, iron sheet and air.

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