A Comparative Study on the Flocculation of Silica and China Clay with Chitosan and Synthetic Polyelectrolytes

Abstract

Flocculation is still one of the most important and efficient processes for water treatment. However, most industrial processes, such as in water treatment plants, still use huge amounts of synthetic polyelectrolytes for the flocculation process. Here we compare the flocculation of two different suspended particles, i.e., silica particles and china clay, with the biopolymer chitosan and two common strong synthetic polyelectrolytes. As a flocculant, chitosan featured a minimum uptake rate of 0.05 mg/g for silica and 1.8 mg/g for china clay. Polydiallyldimethylammonium chloride (PDADMAC) for comparison possessed a minimum uptake rate of 0.05 mg/g for silica and 2.2 mg/g for china clay. Chitosan as an environmentally friendly biopolymer competes with the synthetic polyelectrolytes and thus represents a beneficial economic alternative to synthetic flocculants.

Magnetic ion‐imprinted microspheres for the removal of heavy metal ions from aqueous solution

“…In addition, as can be seen from Figure5c,d, in addition to a large number of nano-microspheres, a small number of micron-microspheres also appeared in the micromorphology of IIM-2. It can be explained that, during the preparation of IIM-2, the high concentration of CTS in subsequent drops began to attract numerous coated nano-microspheres by virtue of chitosan's flocculation function,26,27 and numerous nanomicrospheres flocculated by CTS can formed stably a small number of larger micron-microspheres with the help of cross-linked F I G U R E 2 Fourier transform infrared spectra of chitosan (CTS), polyacrylamide (PAM), Fe 3 O 4 , and ion-imprinted microspheres (IIMs) polyacrylamide. As shown in Figure 5e,f, during the preparation of IIM, the number and size of micron-microspheres in IIM-3 were further increased with the further increase of the concentration of CTS.…”

Chitosan: an overview of its multiple advantages for creating sustainable development poles

“…Several mechanisms have been outlined to explain the coagulating/flocculant action of these biopolymers [75] : (a) neutralization of the negative surface charges of the suspended particles by electrostatic interaction; (b) the simultaneous formation of a bridge between the particles; (c) formation of charge neutralization patches. Reported studies include the separation of clay suspensions [76] , mill effluents treatment during oil palm processing [77] , the harvest of microalgae [78] , protein recovery from fishmeal manufacturing wastewater [79] , textile industry wastewater treatments [80] , etc.…”

A Complementary and Revised View on the N-Acylation of Chitosan with Hexanoyl Chloride

“…Chitosan and modifications thereof have been the target of a vast number of studies [ 1 , 2 , 3 , 4 , 5 , 6 ]. The driving force behind the great number of publications is the biodegradability of chitosan to non-toxic products, the high abundance of the raw biomaterial chitin, and the primary amino group yielding in various types of applications such as the medical sector, environmental protection, wastewater treatment, and agriculture, only to name some of the largest [ 7 , 8 , 9 ].…”