Developing ion exchange membrane from recycled waste expanded polystyrene for heavy
metal removal from industrial wastewater
1.0 INTRODUCTION
4.0 RESULTS AND DISCUSSION
 For Virgin Polystyrene
• An electrospun polystyrene nanofiber mat was treated by immersion in 98% sulfuric
acid (Aldrich) and silver sulfate catalyst with stirring.
• Four different PNIE samples were prepared by changing the sulfonation time. Images
in Fig. 4(b)–(c) show two of the PNIE samples for treatment times of 10 and 100min
• EDS micrographs confirm that the nanofibers were sulfonated.
• The Ion Exchange Capacity(IEC) increases for longer sulfonation times.
• The average fiber diameter is changing as the sulfonation time increases.
• The SEM pictures show that the number of fiber breaks increases as the sulfonation
time increases.
Fig.5. EDS analyzing micrographs and elemental analysis of Sulfur
Fiber Diameter
3000
Ion Exchange Capacity
50
45
Ion Exchange Capacity (g/g)
2500
Fiber Diameter (nm)
Expanded Polystyrene (EPS) is one of the most common forms of packaging and
cushioning material used today. According to the U.S. Post-Consumer & Post
Commercial EPS Recycling Collection Data, in 2010 130 million pounds of EPS was sold
domestically; of this only 37.1 million pounds (28%) was recycled (2010 EPS Recycling
Rate Report, 2010). In its solid form polystyrene is one of the densest plastics
(~1050kg/m3), but when expanded in foam form, EPS is approximately 96% air. These
lightweight, but large volumes of materials fill our landfills and do not degrade.
Heavy metals, such as copper, zinc, nickel, chromium and tin are commonly used in the
electroplating industry to form a thin layer on the various products, and thus, to achieve
high surface resistance against the severity of the environment. The major part of heavy
metals employed in the electroplating process is deposited on the surface of products
being plated; however, a minor part of these heavy metals is discharged as rinsing
wastewater(Kuchar, et al. 2006).Wastewater discharged from industries like plating
processes contains many heavy metals such as copper, lead, chromium, nickel, iron and
zinc etc. have a fatal effect on the human body as well as causing environmental
pollution(Eom, Lee, & Kim, 2005).
In this study, recycled waste polystyrene was electrospun to develop ion exchange
membrane to remove heavy metals from industrial wastewater.
Ihsan Uluturk
Dr. Yong Kim
University of Massachusetts Dartmouth
Bioengineering Department
2000
1500
Fiber Diameter
1000
500
40
35
30
25
Ion Exchange
Capacity
20
15
10
5
0
0
2.0 OBJECTIVE
 Main Objective
Fig.1. EDS analyzing micrographs and elemental analysis of Sulfur
• To develop ion exchange membrane from waste expanded polystyrene (EPS) for
heavy metal removal from industrial wastewater
Fiber Diameter
50
100
Sulfonation Time (min)
0
150
0
Fig.6. The relationship between
sulfonation time and fiber diameter
50
100
Sulfonation Time(min)
150
Fig.7. The relationship between
sulfonation time and IEC
Ion Exchange Capacity
1200
45
1
40
 Specific Objectives:
Ion Exchange Capacity (g/g)
Fiber Diameter (nm)
• To produce electrospun nanofibers from recycle waste expanded styrofoam
• To convert the nanofibers into polymer nanofiber ion exchangers (PNIE)
• To experimentally evaluate the performance of the polymer nanofiber ion exchangers
1000
800
600
Fiber Diameter
400
200
35
30
25
Ion Exchange
Capacity
20
15
(a)
(b)
(c)
Fig.8. SEM images of electrospun fibers of polystyrene (a) untreated PS nanofiber mat
(b) 10 min sulfonated PS nanofiber mat c) 100 min sulfonated PS nanofiber mat
10
5
0
3.0 MATERIALS AND METHODS
5.0 CONCLUSIONS & FUTURE WORK
0
0
50
100
Sulfonation Time(min)
0
150
Fig.2. The relationship between
sulfonation time and fiber diameter
50
100
Sulfonation Time (min)
150
Fig.3. The relationship between
sulfonation time and IEC
 Materials
o Chemicals
Conclusions
•In this work, we investigate recycled waste Expanded Polystyrene (EPS) in an effort to
convert the EPS into Polystyrene nanofibers which is used for membrane materials.
•Also, polymer nanofiber ion exchange fibers (PNIE) were produced by electrospinning
solutions of dissolved polystyrene to produce nanofibers and sulfonating the fiber
surface.
Future Work
•Mechanical, Thermal and Chemical stability of the Polymer Nanofiber Ion Exchanger
membranes could be improved by modifying polymer.
• Silver Sulfate
• Styrene Resin M.w 210,000(Scientific Polymer Inc.)
• Styrofoam
(a)
(b)
(c)
o Solvents
•
•
•
•
Dimethylformamide(Acros Organics)
Tetrahydrofuran(Fisher Scientific)
Sulfuric Acid(Aldrich)
Copper Sulfate
Methods
• Electrospinning
• Sulfonation
 Instruments
• Morphological changes inspected by Joel JSM 5610 Scanning Electron Microscope
(SEM)
• Quincy Lab Inc. AF Model 40 Lab Oven set at 100°C
• Resistance Measured in according to AATCC Test Method 76-2005.
• Atomic absorption spectroscopy(Perkin Elmer AA 300)
• Energy dispersive X-ray spectrometry (EDX, JSM-5610 EDX spectrometer)
Fig.4. SEM images of electrospun fibers of polystyrene (a) untreated PS nanofiber mat;
(b) 10 min sulfonated PS nanofiber mat c) 100 min sulfonated PS nanofiber mat
 For Recycled Waste Expanded Polystyrene
• An electrospun polystyrene nanofiber mat was treated by immersion in 98%
sulfuric acid (Aldrich) and silver sulfate catalyst with stirring.
• EDS micrographs confirm that the nanofibers were sulfonated.
• Recycled waste expanded polystyrene nanofiber ion exchanger membrane has less
fiber breaks than those fibers produced from virgin polystyrene.
• Average Ion exchange capacity of recycled waste expanded polystyrene is smaller
than those produced from virgin polystyrene
• Average fiber diameter of recycled waste expanded polystyrene is greater than
those produced from virgin polystyrene.
6.0 REFERENCES
1. 2010 EPS REcycling Rate Report. Crofton: Alliance of Foam Packaging Recyclers.
2. Eom , T.-H., Lee , C.-H., & Kim, J.-H. (2005). Development of an ion exchange system
for plating wastewater treatment. Desalination 180 , 163-172.
3. Kuchar, D., Fukuta, T., Onyango, M. S., & Matsuada, H. (2006). Sulfidation treatment of
copper-containing plating sludge towards copper resource recovery. Journal of
Hazardous Materials B138, 86-94.
ACKNOWLEDGMENTS
Special Thanks to
•Dr. Chen-Lu Yang - Advanced Technology and Manufacturing Center(ATMC)- University
of Massachusetts Dartmouth