Synthesis
Dissolve industrial crystalline ferrous sulfate in water. Filtration, adding sulfuric acid to the filtrate, heating to 30-45 ° C, and then adding 25-30 mL of nitric acid for oxidation. The solution gradually turned from tan to light reddish brown. Use potassium ferricyanide solution to check whether the ferrous ions in the solution are completely oxidized. The solution was slowly heated until it was smoking and a thick slurry was formed, and the nitric acid and nitrogen oxides were removed. Add water to dissolve, re-evaporate until a crystalline film appears, add water and filtered hot solution of ammonium sulfate to this saturated solution, and add concentrated sulfuric acid. Cool to 0°C under stirring, and filter and crystallize to obtain pure ferric ammonium sulfate.
Physical Properties
The dodecahydrate is lilac to violet crystal (anhydrous compound is colorless); hydrated crystals lose all water molecules at 230°C; readily dissolves in water; insoluble in alcohol; aqueous solution is acidic.
Uses
Iron(III) ammonium sulfate is a mordant in dyeing and printing of fabrics and textiles. The compound also is an analytical reagent; and is used in medicine.
Preparation
Ferric ammonium sulfate is prepared by mixing an equimolar solution of ferric sulfate, Fe2(SO4)3, and ammonium sulfate, (NH4)2SO4. Hydrated crystals are obtained following evaporation and cooling of the solution.
Chemical Properties
pale violet crystals
Preparation
Ferric ammonium sulfate is prepared by mixing an equimolar solution offerric sulfate, Fe
2(SO
4)3, and ammonium sulfate, (NH
4)2SO4. Hydrated crystals are obtained following evaporation and cooling of the solution.
Flammability and Explosibility
Not classified
Purification Methods
Crystallise it from aqueous ethanol.
