From Bench-Scale Experiments to Technical Scale-Up: Rethinking Sorption Research for the Removal of Trace Organic Contaminants from Water

Abstract

Drinking water, wastewater, and stormwater systems are increasingly challenged by trace organic contaminants (TrOCs), including PFAS, pharmaceuticals, pesticides, and other persistent and highly mobile contaminants that occur at ultralow concentrations in complex water matrices. Sorption-based treatment processes remain central to TrOC removal because they can concentrate dilute contaminants without generating potentially toxic transformation products. However, much of the current sorption literature remains disconnected from the needs of performance prediction and technical scale-up. Equilibrium and kinetic parameters are often derived under simplified laboratory conditions, using empirically fitted models, elevated contaminant concentrations, and/or nonrepresentative water matrices, limiting their physical interpretability and transferability across treatment scenarios. This review critically examines three interconnected areas governing the engineering relevance of sorption data: thermodynamic principles governing sorption equilibria, mechanistic interpretation of sorption kinetics, and the evaluation and transition of novel sorbents to scaled treatment systems. By identifying limitations in prevailing experimental practices and aligning equilibrium characterization, kinetic modeling, and sorbent evaluation with application-relevant conditions, this review provides a framework for generating mechanistically grounded sorption data to support material selection and translate laboratory-derived sorption data into process design parameters for pilot- and full-scale TrOC treatment systems.