Purification of Arsenic from Water Using Kitchen-synthesized Magnetite Nanoparticles

1. Background Information • Arsenic contamination is natural in many places in the world, and is the leading contaminant of drinking water. The World Health Organization has set a guideline of 10 ppb (parts per billion) or lower for safe drinking. • Magnetite nanoparticles can more efficiently adsorb arsenic due to their increased surface area and their magnetic properties potentially provide an easy way to remove the nanoparticles from the water after the process is complete. • Magnetite nanoparticles can be easily synthesized with no lab equipment and common household materials, making them an attractive method for removing arsenic from drinking water in remote areas of third world countries. • The primary goal of this study was to determine if kitchen-synthesized magnetite nanoparticles can effectively be used to remove arsenic from drinking water. • This study will shed some light on the process of easy arsenic purification in third-world countries, and could potentially lead to programs to help villagers in these countries get clean water. • The study investigated the feasibility of a simple method for synthesizing magnetite nanoparticles using easily obtainable household materials • The reuse of the nanoparticles was also investigated to determine their efficiency over a period of time. • Procedures • Production of Magnetite Nanoparticles: • Soap was made by mixing lye with olive oil. • Fatty Acid Mixture was produced by digesting the soap in vinegar and heating. • Rust was cooked in the Fatty Acid Mixture. • Nanoparticles were transferred to an aqueous solution, using the previously made soap to emulsify the oily nanoparticles with water. • For each trial: • .5 g of nanoparticles was placed in a 20 ml vial. • 15 ml of 10 ppm (parts per million) arsenic stock solution was added to the vial. • The vial was shaken for 60 minutes. • The magnetite nanoparticles were held at the bottom of the vial with a magnet, and the rest of the solution was poured off and collected for analysis. • The remaining nanoparticles were stored for later trials. Purification of Arsenic from Water Using Kitchen-synthesized Magnetite Nanoparticles • Conclusions • The lab-purchased nanoparticles consistently removed the arsenic to reach safe levels of arsenic. • The data shows that the kitchen-synthesized nanoparticles and resulting carbon matrix did not remove enough arsenic to reach safe levels. • The kitchen-synthesized nanoparticles did succeed in removing at most 22% of the arsenic, showing that the magnetite is capable of purifying water. • The exact cause for the lack of efficiency is unknown, but it may be from the inefficiency of the kitchen synthesis procedure, or other unknown contaminants. • The synthesis method has been shown to not be robust enough to be implemented in the field in its current form • Significant alteration of the method might improve it enough to produce drinkable water. Benjamin Arvey, Hannah Marvin, and Tristan Stickle Nanoparticles attracted to the magnet,. Photo: Tristan Stickle Dispersed Nanoparticles in the Arsenic Solution Photo: Tristan Stickle Heating the Fatty Acid Mixture Photo: Tristan Stickle Sample Tests TEM pictures of kitchen synthesized nanoparticles (on the left), and the commercial nanoparticles (on the right). The kitchen synthesized nanoparticles are about twice the size of the commercial nanoparticles. Photos: Hewlett-Packard Grating the soap into vinegar. (From left, Hannah, Ben, Tristan) Photo: William Stickle Acknowledgements: Thanks to the people from HP who helped make the project possible: Dr. Gallahan, Dr. Stickle, Dr. Eschbach, Mr. Burgess, Ms. Glassman, Mr. Nelles. Revised: 10 October 2014