04/22/2025
By Danielle Fretwell
Candidate Name: Mohammad Bagheri Kashani
Degree: Doctoral
Defense Date: Thursday, May 1, 2025
Time: 1-3 p.m.
Location: Saab Emerging Technologies and Innovation Center (ETIC), Room 445
Committee:
Advisor: Bridgette M. Budhlall, Ph.D., Professor & Associate Chair for Doctoral Program, Plastics Engineering, UMass Lowell
Committee Members*
1. Ramaswamy Nagarajan, Ph.D. Distinguished University Professor, Plastics Engineering, UMass Lowell
2. Weile Yan, Ph.D., P.E., Associate Professor & Associate Chair for Environmental Studies, Civil Engineering, UMass Lowell
Abstract:
In this multidisciplinary research, we present eco-friendly remediation of drinking water and groundwater via various approaches. The first involves an integrated strategy addressing both the removal of PFAS from drinking water and the proactive development of sustainable alternatives to PFAS for the textile and microelectronics industries, while also developing a novel sampler to identify, capture, and quantify toxic contaminants stemming from abiotic dechlorination processes in groundwater.
The safer and effective alternatives to PFAS were introduced in two research projects. In the first project for the replacement of PFAS surfactants in microelectronics, a comprehensive methodology for identifying alternatives to hazardous PFAS was developed and applied. In this approach, alkyl polyglucoside and polyoxyethylene-based surfactants were evaluated as potential substitutes. The findings revealed that etchants formulated with these safer surfactants exhibited superior wetting characteristics compared to their PFAS-based counterparts.
Additionally, the alternative surfactants demonstrated significantly lower toxicity scores. As a result of this work, a cohort of 100
semiconductor manufacturers has adopted these lower-toxic alternatives in their processes.
The second project to replace PFAS involves developing omniphobic PFAS-free coatings for textiles. Novel PFAS-free omniphobic fabric coatings, including long-chain silane and PDMS-based formulations, were evaluated and compared. These coatings offer facile application methods while preserving the mechanical properties of the fabrics. The treated fabrics demonstrated durable, liquid-like brush surfaces that imparted both omniphobicity and strong alcohol repellency. Notably, the coatings maintained their liquid-repellent performance even after repeated abrasion and washing cycles. Toxicity assessments using the P2OAsys tool confirmed that both coatings were significantly less toxic than conventional PFAS-based alternatives.
For remediation of PFAS-contaminated drinking water, our study leverages porous quaternized chitosan microparticles (PQCBs) as a biodegradable and biorenewable adsorbent with tunable porosity and surface charge. By tailoring surface porosity, we demonstrate enhanced PFAS uptake capacity and regenerability, providing a more sustainable and scalable alternative to conventional materials such as granulated activated carbon.
For the remediation of groundwater contaminated with chlorinated solvents, we developed a novel sampler using multifunctional
microcapsules that captured and quantified acetylene, a key by-product of chlorinated solvent degradation. Chlorinated solvents in groundwater are toxic, and they persist for long periods due to their slow abiotic transformation rates. Click chemistry, particularly the azide-alkyne cycloaddition reaction, provides a highly selective and efficient method for tracking transformation intermediates such as acetylene. This study investigates the use of a click reaction-based acetylene sampler to facilitate precise, long-term monitoring of abiotic transformation rates, offering a robust and field-deployable approach for assessing contaminant fates in groundwater systems. Two key components are synthesized and characterized to achieve this: azide-functionalized nanoparticles for selective acetylene capture an alkyne-loaded slow-release microcapsules to ensure controlled reagent availability.