Control of mercury from Kjeldahl wastes

A simple, inexpensive, five-step process that reduces the total mercury concentration of Kjeldahl waste solutions to less than .05 ppm is described. Experimental reagents and procedures used are discussed. The method specifies sodium sulfide to precipitate ionic mercury, followed by a calcium carbonate-aided filtration. The residual mercury content of treated calcium carbonate-filtered effluent ranged from .04-.007 ppm with an average of .02 ppm for 10 determinations. 1 graph, 7 references.