What factors affect the flocculation effect of cationic polyacrylamide (CPAM)?

Cationic polyacrylamide (CPAM) is a commonly used flocculant for water treatment. Factors that affect the flocculation effect and can be controlled manually include the type and dosage of CPAM, wastewater pH, stirring time and settling time, and their reasonable setting is critical to the flocculation effect of CPAM.

Why are non ionic and anionic polyacrylamide based flocculant chains used in tailings treatment?

Non-ionic and anionic polyacrylamide (PAM)-based flocculant chains are commonly employed in a vast majority of tailings treatment operations and several studies have been conducted on degradation of PAMs due to various factors such as pH, light and temperature , microbial degradation and chemical degradation .

Does ultrasonication affect the degradation of polyacrylamide-based flocculants?

The effect of ultrasonication, screening and shearing on five polyacrylamide-based flocculants of similar molecular weight but different degrees of anionicity (DA) was studied through measurement of intrinsic viscosity ( [η]) and size exclusion chromatography (SEC) to investigate the influence of DA on the degradation of polymers.

Does polyacrylamide hydrolyze under acidic conditions?

As reported by Muller et al., polyacrylamides undergo hydrolysis under acidic conditions to yield poly (acrylamide-co-acrylic acid). Amide groups will completely hydrolyze under conditions of appropriately low pH, and polymer weight will remain relatively stable during hydrolysis, as the following formula , , .

How does pH affect polyacrylamide hydrolysis?

Muller et al. , proposed that polyacrylamides would hydrolyze under slightly acidic conditions (pH = 4), and reported that the molecular weight of the polymer remained relatively stable during hydrolysis. Thomas et al. , investigated the effects of different pH conditions and reaction times on the hydrolysis process.

Does hydrolyzed polyacrylamide have a pH dependence?

They discovered that the viscosity of hydrolyzed polyacrylamide exhibits pH dependence as characterized by transition zones (at pH = 3 and pH = 6), where the viscosity suddenly changes. This is because the hydrogen ions adsorb and dissociate from the carboxyl functional groups, a discovery which has significant application potential , .