Synthesis of carbon nanotube membranes from plastics waste for brackish water treatment: Towards nanotechnological recycling

Synthesis of carbon nanotube membranes from plastics waste for brackish water treatment: Towards nanotechnological recycling
Paper details:

need answer to the above question based on my CV and research proposal.

1. Title: Synthesis of carbon nanotube membranes from plastics waste for brackish water treatment: Towards nanotechnological recycling
2. Aims
The water scarcity problem in Australia is being exacerbated by urban growth and, in many regions, by increasingly erratic rainfall patterns due to climate change. Australians rely heavily on groundwater sources, with around 4 million people dependent partially or totally on groundwater for domestic water supply. Treating the brackish groundwater may be a viable community water supply option in regional and remote communities in Australia [1]. Conventional desalination methods are energy and operationally intensive, whereas adsorption-based techniques, although simpler to use, have limited capacity to remove salts [2]. Carbon nanotubes (CNTs) have attracted growing attention as a new material for preparing membranes that may overcome these problems [3,4]. Tip-functionalized nonpolar interior home of carbon nanotubes (CNTs) provides strong invitation to polar water molecules and rejects salts and pollutants. Most of current synthesis methods of CNTs rely on expensive carbon precursors, including such highly pure gases as acetylene, ethane, ethylene and methane [5].
In the pursuit of getting an economical precursor, this research will use waste plastic, especially polythenes of thickness of less than 50 µm that are creating environmental disposal problems. This attempt will not only solve the problem of disposal of waste plastic but also convert the waste (plastic) to wealth (CNTs membranes). CNTs membranes can remove salt as well as organic and metal contaminants. The specific aims of this proposed project are:
Aim 1. to convert waste plastic bags into well-organised carbon nanotubes (CNTs) membranes by a metal-free chemical vapour deposition (CVD) approach using nanoporous anodic alumina membranes (NAAMs);
Aim 2. comprehensive structural and chemical characterization of CNTs-NAAMs and liberated CNTs;
Aim 3. to study the efficiency of CNTs membranes for removing salt, microbes and other organic contaminants from brackish water and monitor the quality of filtered water.
3. Approach
3.1 Fabrication of CNTs-NAAMs
Polyethylene bags will be washed, air-dried and shredded into small pieces. In the proposed project, we will use nonporous anodic alumina membranes (NAAMs) as template for CNTs synthesis to avoid the production of poisonous contaminants due to the use of metal catalysts. NAAMs will be produced by the two-step anodization procedure [6,7]. Then the small plastic pieces and NAAMs will be put into the pyrolysis zone and the deposition zone of the chemical vapour deposition (CVD) reactor, respectively, to start the carbon decomposition process. Argon (Ar) gas will be used to ensure the absence of oxygen during the CNTs synthesis process. The temperature and time conditions will be optimized for obtaining maximum yield through CVD. After the completion of CNTs production, the CVD will be cooled at room temperature and CNTs -NAAMs will be collected and placed in inert conditions. After that the Al2O3 matrix will be dissolved by using solvents such as hydrofluoric acid (HF). Then we will shift the CNTs to ethanol for centrifugation. Structural and chemical characterizations of the prepared CNTs-NAAMs and liberated CNTs will be conducted with scanning electron microscope, transmission electron microscopy, X-ray photoelectron spectroscopy, X-rays diffraction, and Raman spectroscopy using the facilities at AIIM according to an ongoing collaboration between Dr Faisal Hai (supervisor, CME) and Prof Will Price (AIIM).
3.2 Filtration process
Filtration process will become cost-effective if the utilized pressure for water flow is low. In the proposed project, we will utilize filtration employing only the native pressure of the water column in CNTs-NAAMs. The schematic diagram of the working principle of the CNT- NAAMs filtration setup is shown in Figure 1. The CNTs are nearly in contact with each other. The arrows depict flow of water through the CNTs. The water used here will be the brackish water from nearby sources. Then the filtered water will be analyzed for different water quality parameters such as salt concentration, microbes and other organic contaminants. A pilot system will be constructed to assess the performance of the developed system in remote areas. This will be conducted in collaboration with Prof Price (AIIM), who has recently successfully conducted an on-site trial of reverse osmosis desalination of brackish coal seam gas produced water at Gloucester, NSW.
Strategic alignment with host unit: This research will be supervised by Dr Faisal Hai at the School of Civil, Mining and Environmental Engineering (CME) in collaboration with Prof Price (AIIM). Dr Hai’s collaboration with Prof Price strategically focuses on novel membrane processes for water/wastewater treatment. With a well-established capacity for membrane synthesis, membrane processes development and high precision trace organic analysis, Dr Hai’s lab is well placed to support the proposed innovative research.
Project alignment with UOW priority research areas:
The proposed project builds on the strategic research direction and the multidisciplinary research
environment of UOW and will be carried out at the School of CME.
Expected outcomes:
Transforming waste materials through ‘nanotechnological recycling’ will provide a potential solution for minimizing the environmental pollution at the same time producing clean drinking water. Moreover, the carbon nanotube-based membranes may lead to next-generation rechargeable, point-of-use potable water purification appliances with superior desalination, disinfection and filtration properties. The proposed research addresses issues from ARC research priorities. Consequently, this will provide excellent opportunities for ARC and industry funded projects given the current significant interest in water recycling by all stakeholders of the Australian water industry as well as in other countries.
References
1. Works, NSW Public, A. N. Z. E. C. C. Australia, M. F. Microfiltration, P. V. Photovoltaic, U. F. Ultrafiltration, U. V. Ultraviolet, and VWS&T. Veolia Water Solutions. “Brackish groundwater: a viable community water supply option?.”The National Water Commission, Australian Government, Canberra (2011): 1-81.
2. Al-Ahmad, M., FA Abdul Aleem, A. Mutiri, and A. Ubaisy. “Biofuoling in RO membrane systems Part 1: Fundamentals and control.” Desalination 132, no. 1 (2000): 173-179.
3. Das, Rasel, Md Eaqub Ali, Sharifah Bee Abd Hamid, Seeram Ramakrishna, and Zaira Zaman Chowdhury. “Carbon nanotube membranes for water purification: a bright future in water desalination.” Desalination 336 (2014): 97-109.
4. Wang, Haitao, Hanyu Ma, Wen Zheng, Dingding An, and Chongzheng Na. “Multifunctional and Recollectable Carbon Nanotube Ponytails for Water Purification.” ACS applied materials & interfaces 6, no. 12 (2014): 9426-9434.
5. Shajahan, Md, Y. H. Mo, AKM Fazle Kibria, M. J. Kim, and K. S. Nahm. “High growth of SWNTs and MWNTs from C2H2 decomposition over Co–Mo/MgO catalysts.” Carbon 42, no. 11 (2004): 2245-2253.
6. Altalhi, Tariq, Tushar Kumeria, Abel Santos, and Dusan Losic. “Synthesis of well-organised carbon nanotube membranes from non-degradable plastic bags with tuneable molecular transport: Towards nanotechnological recycling.”Carbon 63 (2013): 423-433.
7. Nielsch, Kornelius, Jinsub Choi, Kathrin Schwirn, Ralf B. Wehrspohn, and Ulrich Gösele. “Self-ordering regimes of porous alumina: the 10 porosity rule.”Nano letters 2, no. 7 (2002): 677-680.