Biofiltration for treatment of recent emerging contaminants in water: Current and future perspectives

Abstract

This review article discusses the current state of knowledge on water treatment and reuse by biofiltration systems focusing on biologically enhanced activated carbon (BAC) process. First, the applications of BAC in water treatment systems are overviewed, and then, the mechanisms for both biofilm formation and contaminant treatment are discussed along with the operational parameters influencing the performance of BAC process. Since contaminant removal by BAC is governed by adsorption and biodegradation, both processes are reviewed in relation to the treatment mechanisms. Information on removal of recent emerging contaminants including nitrogenous and unregulated disinfection by-products (DBPs) and their precursors, poly-and perfluorofluoroalkyl substances, nanoparticles, and plasticizers and microplastics by BAC is given along with suggestions for treatment improvements and future research. The uniqueness of this review includes insights on relevant biofilm aspects and the coverage on the abilities of BAC for treatment of recent and less common emerging contaminants especially unregulated DBPs and their precursors, nanoparticles, and plasticizers and microplastics. For future BAC studies, recommendations are proposed on exploring the biofilm development on media and recent emerging contaminants as co-contaminants, as well as developing novel supporting materials such as biochar. © 2020 Water Environment Federation • Practitioner points• The amount and the physiology and physical structure of biofilm affect the treatment efficiency of biological activated carbon. • Biological activated carbon is capable of removing a majority of nitrogenous and unregulated disinfection by-products. • Whether and how biological activated carbon is impacted by and/or can remove nanoparticles, and plasticizers and microplastics remain largely unknown. • Future work on biological activated carbon should focus on biofilm evolution and control, and novel support materials.

Per‐ and poly‐fluoroalkyl substances removal in multi‐barrier advanced water purification system for indirect potable reuse

“…For long‐chain PFAS, bioadsorption has been identified as the primary removal mechanism in BAC treatment because of high log Koc values (Nakazawa et al, 2023; Thuptimdang et al, 2021). This process effectively reduces concentrations of compounds such as PFOS and PFOA.…”

“…treatment because of high log Koc values (Nakazawa et al, 2023;Thuptimdang et al, 2021). This process effectively reduces concentrations of compounds such as PFOS and PFOA.…”

Synthesis of magnetic date stone biochar for solid phase extraction of NSAIDs from water samples

“…5a, the Doehlert model terms with a p-value larger than 0.05 were excluded from the second-order polynomial model. Thus, the equation between the tested factors and the extraction recovery (response) was obtained and described in the following eqn (2). Y = 19.06 -8.20X 1 -30.24X 2 + 15.27X 3 + 5.92X 4 + 3.72(X 1 ) 2 + 51.09(X 2 ) 2 + 9.78(X 3 ) 2 -9.91(X 4 ) 2 À 10.80(X 1 X 2 ) + 20.35(X 1 X 3 ) + 19.88(X 1 X 4 ) -45.10(X 2 X 3 ) + 41.50(X 2 X 4 ) + 4.03(X 3 X 4 ).…”

“…In fact, this step is required to isolate and enrich analytes in environmental samples which are characterized by complex matrices and the presence of trace amounts of analytes. 1,2 Over the last three decades, the development of miniaturized techniques for sample preparation reduced the volume of hazardous solvents and minimized waste generation. 3 In addition, other objectives such as simplification, automation, online integration with analytical instruments, and reduced energy consumption are associated with these miniaturized techniques.…”

The Minus Approach Can Redefine the Standard of Practice of Drinking Water Treatment

“…The Minus Approach can include ozonation prior to BF, as ozonation converts the less biodegradable fractions of NOM into BOM, which can also help remove many KUECs of concern in raw water (e.g., PCPPs and pesticides). , Ozonation should be used cautiously when water contains relatively high bromide concentrations (to avoid bromate formation), and chlorination should not directly follow ozonation, as this can spur halonitromethane formation . Even in the absence of ozonation, BF can remove many KUECs and DBP precursors, particularly many PPCPs, low-molecular weight organics, N-DBP precursors, and pesticides, although removal of less biodegradable compounds may be minimal or require long contact times, especially at low temperatures . BF has proven to be a reliable process even in cold areas like Canada, where cold water temperatures were once thought to limit bacterial growth and feasibility to remove AOC .…”