This talk is not about the usual stuff. Future Directions of Advanced Materials Research, Shimla April 16-19, 2008 A B 20 15 C 10 5 Height (nm) 0 0 100 200 300 400 Distance (nm) Sajanlal and Pradeep, Adv. Mater., 20 (2008) 980 Nanoflowers Sajanlalal and Pradeep - unpublish Particle crystals Shibu et al. Adv. Mater., (2008) In Press. New chemistry Color of gold nanoparticles with endosulfan Example 200 100 2 0 Endosulfan Endosulfan concentration in ppm Color changes with pesticide concentration Pesticide removal Good response at lower concentrations Indian Patent granted Down to 0.1 ppm International patent filed Adsorbed pesticides can be removed from solution Technology commercialized, factory put up J. Environ. Monitoring. 2003 Nanoparticles of silver disappear in a chemical reaction. Inauguration Pesticide removal from drinking water A B Time (minutes) Time (minutes) Product testing stage oking at the social realities through the nan A limited view T. Pradeep [email protected] Water is the biggest business in India. Bottled water – Rs. 2400 Cr Storage filters – Rs. 1000 Cr 2 nm Piped water – Still water is not there for the poor Nanotechnology Applications: Solutions for Improving Water Quality, Mamadou Diallo, Jeremiah Duncann, Nora Savage and Anita Street (Eds.), US Environmental Protection Agency, William Andrew Publishing, 2008 Gas hydrates to ozone chemistry Water - prosperity, health, serenity, beauty, artistry, purity ….. Claude Monet, Waterlilies, 1906 Oil on Canvas, The Art Institute of Chicago Nitrates Fluoride Asbestos …… Microbes Heavy metals Chemicals, pesticides Water filtration: various media hof.povray.org/River.html This is where technologies fail Permissible contamination Time Contamination reaches molecular limits Regulated chemicals as in USEPA regulations for drinking water Regulatory coverage of USEPA for safe drinking water has increased over 4 times since its inception, with revisions in regulations of many old contaminants Classification of USEPA regulated contaminants It is very much clear from the regulations of USEPA, that halogenated organics are going to dominate the future regulative activity Reaching molecular limits - Number of contaminants present in extremely low concentration range (< 1015 molecules per glass of water) are quite significant -Many of those contaminants contain C-Cl bond or metallic in nature Going into the future, a few trends are clearly visible Acetochlor RDX Prometon Metolachlor Terbacil Diazinon - Continued focus of USEPA regulatory activities on various other halogenated organics found in drinking water - Many of these organics are extremely stable in environment, and hence chemistry of novel materials is the need - Continuing with the history, the concentration limits for these organics is expected to be in sub-ppb range So, what are our problems? Images collected from arsenic, fluoride and pesticide affected areas in India For 8-month old Sainaba to 18-year old Ramaswamy, science is yet to deliver its benefits Pictures from the web Why nanotechnology? Problems: Salinity Microbes Organics Available solutions do not take care of the problems Fluoride completely. Arsenic Mercury Cadmium …. Drinking water solutions require new approaches to make clean water affordable. Case Study Problems are indeed serious. Case study: Metal pollution – cadmium in the environment Global Cadmium Production Total (tonnes/year) and % (Source: ICDA/USGS) Ni-Cd Pigment Stabilizer Plating Other battery 16,200 2,000 300 1,400 100 20,000 81% 10% 1.5% 7% 0.5% 100% Source: ICDA Source: ICDA ? Case Study How much of our environment is polluted by cadmium? Fresh water (Source: PCB) Ground water (1995-96) (Source: PCB) Coastal water (Source: PCB) Location Conc Conc. Location State Cd (mg/l) Location (mg/l) (μg/l) Min Max Bellandur Lake, Bangalore 0.70 Off Bombay 80.00 (1980) Korba Madhya Pradesh NT 0.01 Matla River, West Bengal 0.68 Point Calimere 0.1-0.6 (1991) Singrauli Utter Pradesh NT 0.01 Cuddalore 2-27 (1994) Saptamukhi River, West 0.85 Gobindpur Punjab NT 0.08 Bengal Madras Coast 1.4 (1987) Parwanoo Himachal Pradesh NT 0.062 Hugli River, West Bengal 0.59 River Coovum 0.98 (1991) Kala Amb Himachal Pradesh NT 0.150 Subernarekha River, West 0.47 Parangipettai Coast 2-25 (1994) Pali Rajasthan 0.005 0.224 Bengal East Coast NT-2.9 (1999) Jodhpur Rajasthan <0.005 0.042 Nazafgarh Delhi NT 0.013 • The Palakkad controversy showed that excessive withdrawal of ground water can also expose us to high level of metal contamination • The above figures are just tip of the iceberg (itai-itai) – India produces 1.46L tons of e-waste annually – In India, 2M of computers become obsolete every year – 67,000 tons of computer waste contributed 1.1 tons Hg, 4.5 tons Cd and 3012 tons Pb into landfills (Canada, 05) – The average Cd generation per computer is 2.8 g Only two solutions exist for environmental detoxification: Find an alternative eco- friendly way or full recycle and implementation at global scale. Possible in next 5-10 years? Drinking water norms for metal is very stringent and is reaching molecular limits Case Study Illustration of metal adsorption on nanoparticle surface TEM image of Fe nanoparticle and cartoon representation of chemistry at Fe nanoparticle, Iron Nanoparticles: the Core-Shell Structure and Unique XPS wide-scan survey of iron nanoparticles after exposure to a metal Properties for Ni(II) Sequestration, Xiao-qin Li and Wei-xian Zhang, Langmuir salt containing solution, Sequestration of Metal Cations with Zerovalent 2006, 4638-4642 Iron Nanoparticless A Study with High Resolution X-ray Photoelectron Spectroscopy (HR-XPS), Xiao-qin Li and Wei-xian Zhang, J. Phys. Chem. C 2007, 6939-6946 Cartoon representation of chemistry at Fe nanoparticle surface (left) and metal ion removal efficiency for different adsorbents, Iron Nanoparticles: the Core-Shell Structure and Unique Properties for Ni(II) Sequestration, Xiao-qin Li and Wei-xian Zhang, Langmuir 2006, 4638-4642 Landscape of commercial technologies - Broad operating range vis-à-vis - Strong oxidant against contaminants microbes. Fast kinetics. Cheap. Distillation - High initial investment & high Chlorination - Problem of chlorination by- maintenance products. Taste. - High surface area and - High surface area and effective against VOC & effective against VOC & Chlorine Chlorine Activated Ion specific - Not effective against Carbon adsorption - Not effective against microbes, inorganic ions, microbes, inorganic ions, metals Generalist Specialist metals Approach Approach - High surface area and - High surface area and effective against VOC & effective against VOC & Membrane Chlorine Ion Exchange Chlorine Separation - Not effective against - Not for suspended solids, microbes, inorganic ions, microbes. Bacterial growth. metals High costs. - Highly effective against high Reverse - Highly effective against TDS water and removes ions UV treatment Osmosis microbial contamination and high - High cost, brine and pre- efficiency treatment - High cost & discharge removal New technologies are coming – but water is still not affordable. Affordability of Technology We have failed to deliver quality water to people at bottom-of- the-pyramid • What does this cost-of-ownership for access to pure water and income-based societal structure mean to us? – Need for a revolutionary theme for guaranteeing access to pure water to everybody - under INR 1,000 water purifier Universal purifier: Remove suspended particles, pesticides, microbes, metals and anions Zero electricity Minimum maintenance and low-cost of annual replacement (< INR 400/-) • Indeed, early signs of success with nanotechnology shows the promise Solutions available for organics, fluoride, arsenic, mercury, lead, microbes,.. Need to integrate technologies. Introduction to Nano approach Nano is opening newer avenues for solving many of our unsolved problems in drinking water - 62 million affected by fluoride, 35 million affected by arsenic, 30 million affected by water-borne diseases - 134 million residing in rural India, with minimum access to safe water, health amenities and electricity - Many of the drinking water problems are genuinely Indian problems and need an Indian solution Need for affordability and purity Motivation - Nano has opened new doors to - Need for collaboration of solve problems in completely Science with commercial parties novel ways e.g. degradation of Era of novel Science, Selling highly resistant molecules discoveries and Society - No more pure technology development, lets create new - Nano based chemistry being products for Indian consumers surface kinetics driven, can completely change the properties - Newer paradigms in serving of existing materials for the society can be opened purification through solving age-old problems - Any new breakthrough using nano will provide an impetus to India’s technology leadership E. F. Schumacher Pure water can be affordable….. Water Opinions A few interesting words of wisdom • If there is magic on this planet, it is contained in water. Loran Eisely, The Immense Journey, 1957 • Life originated in the sea, and about eighty percent of it is still there. Isaac Asimov, Isaac Asimov's Book of Science and Nature Quotations, 1988 • Water, water, everywhere, nor any drop to drink. The Rime of the Ancient Mariner by Samuel Taylor Coleridge, 1798 • If we could ever competitively, at a cheap rate, get fresh water from saltwater, this would be in the long-range interests of humanity which could really dwarf any other scientific accomplishments.