Nanosilica modified with polyaspartic acid as an industrial circulating water scale inhibitor

Yamin Cheng,Yonghong Cai,Zhongyan Cao,Xiaowei Zhao,Xinyu Guo,Ying Xu,Yufeng Wu

doi:10.1038/s41545-021-00137-y

Yamin Cheng, Yonghong Cai + Show 5 more

Open Access

https://doi.org/10.1038/s41545-021-00137-y

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Abstract

Given the special performance of nanosilica with its small size, large specific surface area and high surface activity, nanosilica containing reactive amino group (denoted as SiO2–NH2) and polysuccinimide were allowed to take part in polymerization reaction to afford SiO2–NH2 modified polyaspartic acid (denoted as SiO2–NH2/PASP), a potential polymer scale inhibitor with good water solubility for industrial circulating water. The scale inhibition performance of the as-prepared SiO2–NH2/PASP was evaluated by static scale inhibition test; and its scale inhibition mechanism was explored by means of scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Results indicated that SiO2–NH2/PASP exhibits excellent scale inhibition performance against CaSO4 and CaCO3 at very low concentrations (optimum scale inhibition rate of 100% and 68%, respectively), and the presence of 5 mg/L of SiO2–NH2/PASP greatly increases the inhibition efficiency of CaSO4 and CaCO3 scale by 21% and 53%, obviously higher than that of pure PASP.

Highlights

The pipeline inner walls of circulating cooling water system often face the challenge of inorganic scale deposition upon exposure to a large amount of poorly soluble inorganic salts, which could cause huge economic losses and operational problems in facilities such as reverse osmosis desalination system, multi-stage flash desalination system, and multi-effect distillation system[1,2,3].it is imperative to introduce a scale inhibitor to get rid of the scale formation on the inner walls of the pipelines of industrial circulating water
Since the scale inhibition performance of polymer scale inhibitors is highly dependent on their carboxyl, hydroxyl, and acylamido groups with strong ionic chelating ability[13,14,15], we introduce these functional groups into the PASP molecule through the copolymerization of L-aspartic acid or the ring-opening modification of polysuccinimide to obtain functionalized PASP
These researches demonstrate that introducing strong chelating groups into PASP molecular chain through ring-opening reaction is favorable for improving the scale inhibition performance; and the ring-opening reaction, with desired environmental acceptance, could be of special significance for the development of polymer–matrix scale inhibitor

Summary

Introduction

The pipeline inner walls of circulating cooling water system often face the challenge of inorganic scale deposition upon exposure to a large amount of poorly soluble inorganic salts, which could cause huge economic losses and operational problems in facilities such as reverse osmosis desalination system, multi-stage flash desalination system, and multi-effect distillation system[1,2,3].it is imperative to introduce a scale inhibitor to get rid of the scale formation on the inner walls of the pipelines of industrial circulating water. At a concentration of 5 mg/L, the complexation and solubilization effect of SiO2–NH2/PASP for CaCO3 is increased by 53% as compared with those of the PASP scale inhibitor (Fig. 4a).

Results

Conclusion