Synthesis and flocculation of a novel flocculant for treating wastewater produced from polymer flooding

ABSTRACT

Preparation of a flocculant which can have high-oil removal and no viscous flocs production for treating oily wastewater produced from polymer flooding (OWPF) is meaningful work. In this paper, a novel flocculant (denoted as PDC₁₂DM) for treating OWPF was prepared by copolymerization of dodecyl dimethylallyl ammonium chloride (C₁₂DM) and dimethyl aminopropyl methacryamide (DMAPMA). By using oil removal and viscous floc production as indexes, the synthesis condition of PDC₁₂DM was optimized. The optimum PDC₁₂DM had an oil removal of 98.8% and a viscous floc production decrease of 62.86% compared with commercial cationic flocculant. Measurement of zeta potential, surface tension, interfacial tension, interfacial film strength and dual polarization interferometry tests were carried out for investigating the flocculation mechanism of PDC12DM. The results showed that PDC₁₂DM can destroy oil droplet stability by electrostatic charge neutralization and demulsification together. Especially, demulsification mechanism is helpful for reducing the viscous floc.

GRAPHICAL ABSTRACT

KEYWORDS:

• Wastewater produced from polymer flooding
• flocculant
• copolymer
• flocculation mechanism
• interface

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The funding is National Science and Technology Major Project Sub-project of China (grant number: 2016ZX05025-003-003) and the National Natural Science Foundation of China [grant numbers 21607174 and 51974267].