Synthesis and characterization of bulk functionalized polyurethane foams for lead ion removal from water at ppb levels Cristian Bonilla Subhashini Gunashekar Dr. Nidal Abu-Zahra OBJECTIVE  Preparing a bulk functionalized polyurethane foam containing sulphonic acid groups as ion exchange media to remove Pb 2+ from water.  Determining the main physical properties of the foam and chemical structure through a detailed characterization. MOTIVATION  Lead is a toxic heavy metal that is harmful to human health.  The occurrence of lead in drinking water is mainly from corrosion of lead pipes and solders and faucets made with leaded brass, especially in areas of soft and acidic water.  Long-term exposure is toxic and high levels of lead contamination in a child can result in convulsions, major neurological damage, organ failure, coma, and ultimately death.

POLYURETHANE FOAM SYNTHESIS Experimental set up – Raw materials reacted at 70 o C in a nitrogen atmosphere Prepolymer containing functionalized groups capable of removing lead ions Addition of blowing agent to initiate foaming Foaming Pre-polymer Cast Open cell Polyurethane Foam RESULTS a. b. c. d. e. f. (a) FTIR spectrum of samples A1-A4 (b) FTIR spectrum of samples B7-C10 (c)High and low molecular weight compounds on the samples based on BES/DMSO content (d)EDX elemental analysis (e)SEM image of polyurethane foam at 50X magnification (f)Lead removal efficiency based on BES/DMSO molar content

RESULTS (cont.) (g) Lead removal efficiency based on PPG/TDI molar content (h) Lead removal efficiency with variable CERT Foam 1 st Run 2 nd Run3 rd Run PH AND MULTISTAGE BATCH ANALYSIS g. h. i. j. k. (i) Multistage batch filtration process set-up (j) Lead removal capacity from multistage filtration process (k) pH analysis of functionalized polyurethane foam CONCLUSION  The foam with the molar composition of 1 mole of PPG, 2 moles of TDI, 0,6 moles of BES, and 4 moles of DMSO with a CERT of 40 min seemed to be the most stable structurally and had the highest Pb 2+ removal efficiency of 47ppb/g for 1 h exposure in 100 ppb Pb 2+ solution.  Higher amounts of foam samples in a multistage batch filtration set up increased the Pb2+ removal efficiency.  The functionalized polyurethane foam performed better at lower pH levels, after exposure times of two hours.