Coal quality inspection

Firstly, the coal sample is crushed below 0.2mm and burned to ashes. The ash is treated with acid, the volume is constant, and the clear liquid is filtered out for the determination of Fe2O3 (iron), Al2O3 (aluminum) and Cao (calcium).

Iron can be complexed with 1, 10- o-phenanthroline, and the general method for iron determination according to GB9739.

According to GB9734 "General Determination Method of Aluminum", aluminum was determined by complexometric titration with aluminum reagent (ammonium tribasic carboxylate). (The above two solutions can be appropriately diluted or concentrated according to the content of ions to be detected).

Calcium can be determined by titration with EDTA standard solution under certain conditions.