Wet-Nanotechnology and Nanofluids: Nanoparticles and Water Quality
M. Kostic
Department of Mechanical Engineering, Northern Illinois University
www.kostic.niu.edu/DRnanofluids
Water is ranked as second, after energy, among the Humanity’s Top Ten Strategic Problems in the next 50 years. Demand for quality water is rising due to limited supplies of freshwater, extended droughts, population growth, and decline in water quality due to increasing groundwater and surface water pollution as well as increasing demands from a variety of competing industries. The coupled physical, chemical and biological processes that influence water quality in natural and industrial systems are complex and include clusters, macromolecules, nanoparticles and colloids. Functional nanoparticles can be designed and synthesized to act as both reaction and separation media for pollutants, or as carriers and delivery vehicles for chemical and/or bioactive compounds; thus providing unforeseen opportunities for development of more efficient and cost effective water purification processes and systems.
Many of the problems involving water quality could be resolved or minimized with advancement in nanoscale science and engineering, such as use of nanosorbents, nanocatalysts, bioactive nanoparticles, nanostructured catalytic membranes, and nanoparticle enhanced filtration, among other products.
Use of different innovative and functional nanoparticles in water purification media or embedded in membranes may effectively (and ultimately inexpensively) contribute to the purification of surface water, groundwater and industrial wastewater, contaminated by toxic metal ions, radionuclides, organic and inorganic solutes, bacteria and viruses. Many challenges but also opportunities exist with utilization of advanced nanomaterials and innovative technologies.
Selected Activities of Prof. Kostic's Nanofluid Research Group (more at www.kostic.niu.edu/DRnanofluids):
► Kostic, M and Simham, K.C., Computerized, Transient Hot-Wire Thermal Conductivity Apparatus for Nanofluids-Best HMT09 Conference Paper, Proceedings of the 6th WSEAS International Conference on HEAT and MASS TRANSFER (HMT'09), Ningbo, China, January 10-12, 2009. In RECENT ADVANCES in HEAT and MASS TRANSFER (Editor: Lifeng Xi), ISBN: 978-960-474-039-0; ISSN: 1790-5095, p. 71-78, WSEAS Press. 2009. (Also, Plenary Lecture: Heat Transfer, Thermal Energy and Entropy - Demystified )
A new and improved HWTC apparatus for thermal conductivity measurements of (nano)fluids has been recently developed. It employs innovative solutions for easy calibration of uniform Platinum wire tension and thus minimizing the strain influence on temperature measurement (i.e., minimizing the well-known and unwanted “strain-gage effect” on Pt-wire electrical resistivity); measurement of Pt-wire voltage drop independently from power wiring (four wires); and an effective off-centered mechanical design to minimize the fluid sample size (about 30 mL), but at the same time providing additional space for wiring (including three inside thermocouples for fluid temperature uniformity verification). Data acquisition hardware and software are optimized to minimize signal noise and enhance gethering and processing of useful data.
► Prof. Kostic has been awarded a NSF research grant (CBET-0741078 Thermal Transport & Thermal Processing) for "Exploring New Hybrid Polymer-Nanofluids with Enhanced Flow and Heat Transfer Characteristics," in 2007/2008.
►
Kostic, M., M. Golubovic, J.R. Hull and S.U.S.
Choi,
ONE-STEP METHOD FOR THE PRODUCTION OF
NANOFLUIDS, ANL invention S-105,821.
US Patent Number:
US 7,718,033 B1,
(PDF),
Publication Date 18 May 2010.
►
Kostic, M., M. Golubovic, J.R. Hull and S.U.S.
Choi,
One-Step Method
for the Production of Nanofluids, ANL invention
S-122,261,
U.S. Patent-Divisional Application No.12/729,494
filed by U.S. Department of Energy
(Brian John Lally/Katherine Baldwin, Patent Attorney) on
3/23/2010.
Additional Claims to the above.
► Kostic, M., “Critical Issues and Application Potentials in Nanofluids Research,” ASME-MN2006 Multifunctional Nanocomposites 2006 International Conference, September 20-22, 2006, Honolulu, Hawaii, ASME Proceedings, New York, 2006. (PPT & Photos or Seminar)
► Kostic, M., Effective Thermal Conductivity Errors by Assuming Unidirectional Temperature and Heat Flux Distribution Within Heterogeneous Mixtures (Nanofluids), (*) HMT'08-The5th WSEAS International Conference on HEAT and MASS TRANSFER, ID: 573-354, Acapulco, Mexico, January 25-27, 2008. Abstract: It is common practice to approximate temperature distribution and heat flux as unidirectional for heterogeneous mixtures if exposed to “over-all unidirectional” boundary conditions. This approach has been used to model and to arrive at the effective (or over-all average) thermal conductivity of heterogeneous mixtures (nanofluids). It is shown here, however, that due to the heterogeneity of system structure and properties the temperature distribution and heat flow will not be unidirectional (one-dimensional) and the errors due to such unrealistic (physically impossible) approximation may be much higher than anticipated.
►Nanofluid
Flow-and-Heat-Transfer Apparatus *
►NIU-MK Nanofluids Activities and Future Plans
