Question

Q.1.a. Read and decipher US Patent 6 861 039 BI. i. Summarize the sulfide coagulation method for removing arsenic impurities from phosphoric acid ii. Summarize the hydrogen halide proposed method for removing arsenic impurities from HsPO Q1.b. For the chloralkali process utilizing the Downs Cell, why can calcium chloride be used? Need two primary reasons and a short statement explaining its use Ql.c. State the two step process (as complete, balanced and notated chemical equations) for removing hydrofluoric acid from phosphoric acid production when using fluoroapatite and sulfurie acid. Caustic soda Q.l.d. Briefly describe the significance of superphosphate fertilizer: That is, how is it made, and what is its chemical formula, and describe its water solubility.

Answer 1

Ans: the hydrogen halide method for removing arsenic impurities include bringing phosphoric acid containing arsenic into contact with hydrogen halide in presence of compound capable of generating hydrogen halide under acidic conditions.wherein compound capable of generating hydrogen halide under acidic condition is halide of iron(2),copper(1),or tin(2) thereby to remove the arsenic from phosphoric acid