Flocculating Agents

Abstract

Flocculating agents are chemical additives that cause suspended solids to form aggregates called flocs. These agents are used in water treatment, municipal and industrial waste treatment, mineral processing, and papermaking. Flocculating agents are either inorganic salts or water‐soluble organic polymers. They act by shrinking the ionic double layer, or neutralizing the surface charge of suspended particles, or bridging between particles. The type of flocculant used depends on the type of solid–liquid separation being performed. The physical properties and size of the flocs as well as the rate of floc formation are the critical parameters in this process. Flocculants are usually selected by the results of laboratory‐scale experiments. The manner in which the flocculating agent is mixed with the substrate can affect the results. Special analytical methods are used for some flocculating agents. Some agents or impurities in them may present toxicological or environmental problems. The general economic trend is the replacement of inorganic salts with organic polymers, which give improved performance.

Copolymerization of N-[3-dialkylaminopropyl]methacrylamides with acrylic amides and esters in organic solvents

“…Полимеры на основе замещенных акриламидов нашли широкое применение в таких традиционных для них областях как флокуляция [1], использование в качестве добавок в бумагу [2], в нефтедобыче [3], для получения различных покрытий [4,5]. В последние десятилетия большое внимание замещенным акриламидам уделяется в связи с бурным развитием направления создания, исследования и применения стимулчувствительных полимеров [6].…”

Concentration effects in the base-catalyzed hydrolysis of oligo(ethylene glycol)- and amine-containing methacrylic monomers

“…[ 1,2 ] HEMA copolymers are used for producing coatings and adhesives,[ 3,4 ] DMAEMA copolymers are effective flocculants and additives to paper. [ 5,6 ] In most cases, the preparation of such polymers is carried out in aqueous media. Furthermore, the monomers such as OEGMAs or DMAEMA salts are often obtained, stored and used in the form of concentrated aqueous solutions.…”