Effect of aluminum ion on sedimentation of kaolinite using anionic polyacrylamides as flocculant based on two-dimensional fractal dimension

ABSTRACT

Based on 2D fractal dimension, the effect of aluminum ion (Al³⁺) on kaolinite flocculation using anionic polyacrylamides (APAMs) as flocculant has been investigated at pH 4. The settling performance was tested, and fractal dimensions of flocs were analyzed. The results show that the clearer the supernatant, the bigger fractal dimension was obtained using APAM in distilled water. With the addition of Al³⁺, the supernatant turbidity increases first and then decreases, while the trend of fractal dimension with Al³⁺ concentration is opposite. Zeta potential results indicate that different sedimentation performance and floc fractal dimension of kaolinite are caused by the different APAM flocculation mechanism.

KEYWORDS:

• Aluminium ion
• flocculation mechanism
• fractal dimension
• Kaolinite sedimentation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Nature Science Foundation of China (Grant Number 51574240 and Grant Number U1704252).