The application of non-oxidizing biocides to prevent biofouling in reverse osmosis polyamide membrane systems: a review

Abstract

Biofouling of polyamide membranes is one of the main barriers faced by reverse osmosis (RO) technologies to supply fresh water. Currently, biofouling is addressed by feed water pretreatment using chlorine, followed by membrane cleaning. Chlorine damages polyamide membranes and also generates harmful disinfection byproducts. Thus, safer strategies are needed to prevent biofouling in polyamide membrane systems. This review investigates the applicability of the following non-oxidizing biocides in preventing and controlling biofouling in RO systems, including their antimicrobial efficiency, hazard levels, membrane compatibility, and applicability to drinking water treatment: (1) 2,2-dibromo-3-nitropropionamide (DBNPA); (2) 2-methyl-4-isothiazolin-3-one (MIT); (3) sodium bisulfite (SBS), (4) phenoxyethanol (PE), (5) sodium benzoate (SB). According to this review, MIT and DBNPA present most of the features attributed to an ideal anti-biofouling chemical but also are the most hazardous biocides. Due to safety and efficacy, none of the five chemicals were determined to be the final solution to address membrane biofouling. However, alternative RO biocide research is in early development and requires further investigation via biofouling prevention studies. Therefore, future research efforts on the investigation of economic, eco-friendly, and safe antifouling agents to prevent and treat biofouling in RO systems are paramount to promote sustainable water supply in water-stressed countries.

Active-Bromide and Surfactant Synergy for Enhanced Microfouling Control

“…This aligns with the established limitations of chlorine-based biocides, where the EPS matrix of bio lms can hinder the penetration and e cacy of the biocide [9,16].…”

“…In recent years, various alternative biocidal strategies have been explored to address the limitations of chlorine-based disinfection. These include non-oxidizing biocides such as isothiazolinones and quaternary ammonium compounds (QACs), enzymatic biocides, and ultraviolet (UV) irradiation [5,9,10]. However, each approach has its own limitations, such as potential toxicity concerns, high operational costs, or limited effectiveness against established bio lms.…”

Variation of Tolerance to Isothiazolinones Among Daphnia pulex Clones

“…Isothiazolinones are remarkably efficient as biocides against microorganisms, but this efficacy also portends their potential as human and environmental hazards (Da- Silva-Correa et al, 2022;Kresmann et al, 2018). The sensitizing and allergenic effects of CMIT and MIT on human health have been well established, and have led to the restriction of their concentrations in personal care products (ECHA, 2015;Kim et al, 2019), but their toxicity to aquatic organisms has received less attention (ECHA, 2014(ECHA, , 2015.…”

Effects of Ethyl Lauroyl Arginate (LAE) on Biofilm Detachment: Shear Rate, Concentration, and Dosing Time

“…In contrast, non-oxidizing biocides with broad-spectrum antimicrobial effects and good compatibility with polyamide membranes, such as 2,2-dibromo-3-nitrilopropionamide (DBNPA) [27], are successfully applied in some reverse osmosis (RO) plants [28]. Ethyl lauroyl arginate (LAE), a preservative and cationic biocide, is widely used in food and medical fields, and was approved by the Food and Drug Administration (FDA) in 2005 [29].…”