Particle speciation analysis of inorganic polymer flocculants: an examination by photon correlation spectroscopy

Abstract

The particle size distribution for two typical kinds of inorganic polymer flocculants is characterized comparatively by using photon correlation spectroscopy (PCS). The experimental results indicate that there exists large difference in particle speciation distribution between PFCl and PACl prepared under similar conditions. The particle size of PFCl samples range in a narrow distribution. Their mean effective hydrodynamic diameters calculated by translational diffusion coefficient are between 5 and 11 nm. For PACl samples at certain basicity, no visible particle species can be determined. At high basicity, both laboratory prepared and commercial products, show a bimodal distribution: one in 2-5 nm and the other ranges in several decades of nm with wide distribution. The latter may be colloidal aluminum hydroxide and also some aggregates of polymers.

Modified Inorganic Polymer Flocculant-PFSi: Its Preparation, Characterization and Coagulation Behavior

“…The experiments were run on Beckman DU650-UV-Visible Spectrometer. The PCS measurements were performed on a Brookhaven Model BI-200SM servomotor-controlled light scattering gonimeter with a Model BI-9000AT autocorrelator (Wang et al, 2000). The incident light source was a 35 mW He-Ne laser operating at a 632.8-nm wavelength with vertical polarization.…”

“…It is evident that some of copolymerized species or aggregates between silica and iron(III) polymers are formed. By decreasing the Si/Fe ratio, the particle distribution becomes typically that of PFCl Wang et al, 2000), i.e., exhibiting a narrow distribution with particle diameter at several nm. …”

Characterization of hydrolyzed Fe(III) species produced in Fenton’s reaction

“…The effective particle size diameter (d eff ) for polymer flocculant was characterized comparatively by using photon correlation spectroscopy (PCS) [21]. The PCS measurements were performed on a servomotorcontrolled light scattering meter (Model BI200SM, Brookhaven Instruments, Holtsville, NY, USA) equipped with an autocorrelator (Model BI9000 AT, Brookhaven Instruments).…”

Effect of base addition rate on the preparation of partially neutralized ferric chloride solutions

“…After aging for 24 h, the size distribution was unimodal and the mean sizes of polymer were found to vary from 12 to 20 nm as the B value increased from 1.0 to 2.0. Wang et al [20] reported that 5-11 nm polyferric chloride was observed at higher B by using PCS. In our experiment, unimodal distributions having a mean size of ∼5 nm were observed for B = 1.0 and B = 2.0 at R B = 1.2 min −1 ; however, bimodal distributions were observed for both B = 1.0 and B = 2.0 at R B = 0.012 min −1 .…”

“…In spite of numerous studies made using potentiometry, UV-vis spectrophotometry, centrifugation and electron microscopy, and more recently using photon correlation spectroscopy (PCS) [18][19][20], the factors that determined subsequent precipitation or polymerization in a partially neutralized FeCl 3 solutions were still not well understood. Literature indicated that lower hydrolysis ratios, B, led to ferric hydroxide precipitation, whereas higher B favored polymerization [5].…”