Coagulation and Flocculation
Coagulation and flocculation is the process of destabilizing, aggregating, and removing colloidal particles from liquid suspension by the formation of what is known as a floc. This process typically requires the addition of chemical compounds know as flocculants, coagulants, or clarifying agents. These additives speed up and the process, enhance clarity, increase floc density, and improve dewatering of sludge and flocs. Flocculants can be categorized into one of two groups; organic and inorganic.
These flocculants are typically salts of multivalent metals. The cationic component in these salts is able to neutralize the charge of suspended particles to facilitate flocculation. Aluminum and iron salts are the most commonly used for water treatment.
These chemicals compounds are water soluble polymers and can be cationic, anionic, or nonionic in nature. Similar to inorganic flocculants, organic flocculants interact with the surface of suspended contaminants and cause them to flocculate. Polyacrylamides, chitosan, and glutamic acid are all commonly used organic flocculants. As mentioned above organic flocculants are polymeric in nature and are produced by free radical polymerization reactions. These reactions require the use of a free radical initiator in order to kick off polymerization.
Vazo™ Free Radical Initiators
Vazo™ is a line of substituted azonitrile compounds that are the ideal free radical initiators for producing water soluble cationic and anionic polymeric flocculants, clarifying agents, and coagulants. When exposed to increased temperature or UV light, Vazo™ molecules decompose to form two free radicals and nitrogen gas. These free radicals will not abstract hydrogen from growing polymeric flocculants, coagulants, and clarifying agents during production. This decreases the chance of branching and allows for more control over the final polymers molecular weight and structure. This results in flocculants, coagulants, and clarifying agents that can produced in a highly predictable and reproducible process that perform as intended.
As stated above, polymerizations that are initiated with Vazo™ are predictable and easily controlled. This allows for the production of anionic and cationic flocculants with very tight specifications that flocculate suspended contaminants at a very high level. In addition, Vazo™ initiators are much safer than traditional free radical initiators like peroxides that have a tendency to undergo a rapid exothermic reaction if not stored properly. If you are looking for a safe and efficient initiator for your flocculant, coagulant, or clarifying agent polymerizations contact us today to request your sample of Vazo™.