Metal Precipitants
Chemical precipitation using metal precipitants is a very common treatment modality used to remove dissolved, cationic, metals from solutions such as metal finishing and plating streams. The dissolved metals are converted to an insoluble form, a suspended solids that is, by the chemical reaction between the Tramfloc 900 Series Metal Precipitants and the metallic cation. The particulate matter formed in this reaction are precipitated from solution by settling and sometimes but subsequent filter apparatus. This treatment protocol often includes neutralization, precipitation, coagulation/ flocculation, solids/liquid separation and dewatering with a plate and frame filter press.
The effectiveness of such an application depends upon such as: specific cations and their concentration, Tramfloc 900 Series Metal Precipitants formulations, system pH, contra-indicating or competing ions. A common method to drop out metals is to use an hydroxide contributor, such as caustic, which allows metal hydroxides to form. They are usually highly insoluble and precipitate readily at optimum pH levels, such as about 7.75 for Cr+3 or about 11.0+ for Cd. Metal hydroxides are amphoteric, which means soluble at both ph extremes. Sometimes it is necessary to combine more than one treatment modality to accommodate various soluble metals present in the process stream.
Tramfloc, Inc. offers metal precipitants which do not employ the hydroxide method. Tramfloc 900 Series Metal Precipitants form highly insoluble and stable compounds with many different cations in the carbonate, sulfide and carbamate forms. These compounds with multiple metals are formed with a Tramfloc 900 Series Metal Precipitants formulation and remain insoluble at pH extremes.
Plating, IC, metal finishing and other process streams sometimes contain chelators and other complexing molecules which bond with cations and prevent precipitation. The hydroxide method is ineffective in the presence of chelants such as NTA, EDTA, citrates etc. Tramfloc 900 Series Metal Precipitants destroy chelant bonding and allow precipitation of suspended solids which lend themselves more effectively than hydroxide compounds to efficient sludge dewatering and reduced TSS volumes. When a stream has multiple metals, their concentrations can be reduced to MCL by Tramfloc 900 Series Metal Precipitants, post pH treatment. Contact Tramfloc, Inc. for technical support by calling 888-929-8973 or messaging us, water@tramfloc.com
