Research on the coagulant aid effects of modified diatomite on coal microbial flocculation

Abstract

Diatomite was modified by chitosan to prepare modified diatomite, and the modified diatomite in an optimized ratio was utilized in coal bio-flocculation. The interaction behavior and flocculation mechanism of modified diatomite on coal slurry water were investigated by single factor experiments, infrared spectroscopy, Brunauer-Emmett-Teller (BET) measurements, and zeta potential measurements. The single factor experiments showed that when the amount of microbial flocculant added was 1.5 ml, the temperature of coal slurry water was 39 °C, the pH was 5, and the amount of modified diatomite was 0.2 g, after 30 min of sedimentation, the flocculation transmittance of the coal slurry water reached 84.3%. The infrared spectra showed that the -NH2 and -OH of the chitosan molecule had a polar interaction with the Si-OH bond in diatomite. The BET measurements showed that the specific surface area of diatomite was not a decisive factor affecting the flocculation effect. Zeta potential measurements indicated that the amino protonation of chitosan increased the isoelectric point (IEP) of modified diatomite. These results showed that modified diatomite has a good effect on coal bio-flocculation.

Adsorption Properties of Diatomite Minerals on Glyceryl Monostearate for Antifogging of the Plastic Film

“…34 The tensile vibration peak of Si−O−Si was observed at 618 cm −1 , and the antisymmetric bending vibration peak of O−Si−O in silico-oxygen tetrahedron was 480 cm −1 , which were characteristic peaks of SiO 2 in diatomite particles. 35,36 The distinctive peak of Si−OH and adsorbed water on the diatomite particles was found at 3447 cm −1 , while the torsional vibration of Si−OH on the surface of the diatomite samples was responsible for the weak absorption peak at 1624 cm −1 . 37 The Si−OH on the diatomite surface was an important functional group, which could be divided into two types: one is isolated and the other is connected by a hydrogen bond, which made the diatomite surface appear weakly acidic.…”

Settleability and Dewaterability of Sewage Sludge with Modified Diatomite

“…However, natural diatomite directly used as a conditioner cannot fully meet the demand of the sludge dewatering and the environment yet. Pore size distribution, impurity content and bulk density are the main factors affecting the quality of catalyst carrier, so it is necessary to further improve the physical and chemical properties of diatomite (Danildenamor et al 2012;Dong et al 2020).…”