(154d) Organic and Biofouling of Polymeric Membranes: Mitigation Using Surface Graft Polymerization and Assessment with Fouling Analytics

Membrane processes require both mitigation and management of fouling to ensure viable process economics, and performance that meets required standards in terms of selectivity or separation effectiveness.

In this talk we will discuss mitigation approaches that focus on surface modification of poly(ethersulfone) membranes using plasma or photo-initiated graft polymerization. We will show that selection of graft moieties is aided by employing a high throughput screening process, which is able to identify surfaces having antifouling properties for a range of feeds. Examples will be provided for feeds of interest in water purification, including humic substances, extracellular polymeric substances modeled by sodium alginate, and microbial fuel cell effluent. In addition, we will show that biofouling can be controlled using both amines and zwitterionic surfaces (betaines).

Membrane surface modification can be employed to fulfill multiple objectives of reducing flux decline and improving rejection. An example will be presented to show how surface charge can be manipulated to improve the rejection of oxyanions found in contaminated groundwater while preserving antifouling properties toward humic substances.

Fouling analytics â?? including models that describe the rate of flux decline â?? can be used to help manage the impact of fouling on membrane processes. In this talk we will show how such analysis can be used to interpret data from screening studies and aid in membrane selection, reduce energy consumption, and optimize cleaning schedules to control the temporal progression of fouling, especially as different fouling mechanisms evolve.