Metals, such as mercury, may be removed from aqueous, hydrocarbon, or mixed oilfield or refinery fluids by: applying a sulfur compound having the general formula HS—X, where X is a heteroatom substituted alkyl, cycloalkyl, aryl, and/or alkylaryl group either alone or in combination with or as a blend with at least one demulsifier, a buffering agent, a pour point depressant, and/or a water clarifier to chelate the at least one metal and form a chelate complex of the sulfur compound with the at least one metal and then separating the chelate complex from the fluid.