Crosslinking Phenolphthalin based Poly(arylene ether sulfone) and Its Effect on Nitrate Remediation
Board Location: #71
Discipline: Chemistry and Chemical Sciences
Subcategory: Chemical/Bimolecular/Process Engineering
Session: 1
Simeon Newman - Florida Agricultural and Mechanical University
Co-Author(s): Nichole Boyer, Florida Agricultural and Mechanical University, Tallahassee, Fl; Dr. Natalie Arnett, Florida Agricultural and Mechanical University, Tallahassee, Fl.
Nitrates are essential nutrients required for living organisms which are highly mobile in nature and easily released in the soil and water through bacterial activities. Wastewater containing excess nitrate anions, not only cause adverse effects on different ecosystems but may risk to human health due to shortness of breath, cancer and blue baby syndrome. This research focuses on utilizing phenolphthalin based poly(arylene ether sulfone) (PPLn-PAES) homopolymers and crosslinked films for nitrate remediation from aqueous medium. PPLn-PAES films were crosslinked at high (200 °C) and low (150 °C) temperatures for 30 to 240 minutes. Remediation studies were conducted by immersing PPLn-PES in a 100 ppm sodium nitrate (NaNO3) solution for at 1-, 3-, and 6-day intervals. The chemical composition of PPLn-PAES homopolymer was confirmed by NMR and ATR-FTIR analysis. 1H NMR showed the appearance of the peaks related to protons adjacent to the ether linkage on PPLn and DCDPS at approximately 7.56 (f) and 7.32 (e) ppm. The highest degradation temperatures (382 °C) was exhibited by the 4H-HT film. DSC analysis of PPLn-PAES before and after crosslinking showed a loss the initial Tm peak intensity with increased curing temperature and time. All the studied films exhibited >98% nitrate removal at day 6. Kinetic studies conducted to determine the most suitable isotherm exhibited higher R^2 values when the Freundlich Model was employed indicating multilayer adsorption on heterogeneous adsorption sites. Further modeling was carried out to understand the mechanism that mediated adsorption and future research will include using aquaporins to test the feasibility of adsorption in nature.
Funder Acknowledgement(s): NSF DMR 2122142
Faculty Advisor: Dr. Natalie Arnett, natalie.arnett@famu.edu
Role: I assisted in completing 180 replicates for the adsorption and desorption studies. I also modeled the polymers using MATLAB and excel to determine the mechanism of adsorption and the isotherm kinetic models. I characterized the polymers using ATR-FTIR, DSC, and TGA before and after crosslinking them. Lastly, I statistically characterized the design of my experiment to ensure that this was repeatable.