Gas stream multi-pollutants control systems and methods

A non-hazardous composition comprising carbonates, bicarbonates, or a combination thereof, and mercury, a mercury derivative, or a combination thereof, wherein the carbonates, bicarbonates, or the combination thereof have a relative carbon isotope composition (δ13C) value less than −5.00‰ wherein the mercury is in a non-leachable form in the composition, and wherein the composition, when subjected to a leaching process comprising

• preparing 2×1 L of an extraction fluid comprising an aqueous solution of acetic acid, wherein each 1 L of the extraction fluid comprises 5.7 mL acetic acid in deionized water;
• grinding the solid such that particles of ground solid are less than 1 cm in the narrowest dimension if the particles are not already less than 1 cm in the narrowest dimension;
• placing 100 g of the ground solid into an extraction vessel with 2 L of the extraction fluid to produce an extraction composition;
• rotating the extraction vessel in an end-over-end fashion for 18±2 hours at room temperature;
• filtering the extraction composition through borosilicate glass fiber with a pore size of 0.6 μm to 0.8 μm to produce a leachate;
• and
• adjusting pH of the leachate with 1 N nitric acid to a pH of pH 2 or less than pH 2;
• produces a leachate comprising less than 2.0 mg/L of mercury.