When mixed with water, Remotox decomposes to form bisulfide, aqueous hydrogen sulfide and other sulfur compounds. Most heavy metal ions are precipitated as metal sulfides by these breakdown products. See Calcium Polysulfide for Treatment of Heavy Metals and Cyanide. Metal sulfides are much less soluble than metal hydroxides. Metal hydroxides change solubility with changes in pH. Metal sulfides remain insoluble within a wide pH range.
In the case of chromium, Remotox reduces hexavalent chromium to trivalent state which then precipitates as chromium hydroxide in a one-step reaction; therefore, no need for bisulfite, metabisulfite, sulfur dioxide or sulfuric acid.
While effective treatment can be achieved over a wide pH range, best results are typically obtained within water system pH 7-10. See pH Guidelines for Treatment of Soluble Metal Streams. Ensuring adequate contact time and thorough mixing is critical to successful treatment. Dewatering the resulting precipitate can be expedited by employing an anionic flocculant.
For additional information, heavy-metal removal studies, samples or assistance, please contact us at 623-328-5175 or by email at firstname.lastname@example.org.
Many industries, including metal finishing, printed circuit board manufacturing, food processing and mining operations, produce waste streams containing significant amounts of metals.
Remotox® is commonly used for cost-effective removal of heavy metal ions and other inorganic compounds from various wastewater sources.