Estudis d’interacció entre nanopartícules de plata i sòls agrícoles: efectes en la forma i mida de les nanopartícules

Abstract

Nowadays, the use of nanoparticles has been incorporated into many aspects of our daily lives. Either because they are generated by natural phenomena or because they are increasingly used in products that we use during the day to day as personal hygiene products or disinfectants, or simply because it is a field in which much work is being done to improve medical, technological products... Many of these nanoparticles reach the wastewater, which goes to the sewage treatment plants. Many of these wastewater and sewage sludge end up reaching agricultural land. According to some studies that have been carried out in recent years, these nanoparticles can interact with the soil and this interaction depends on their soil characteristics, such as the ion exchange capacity, conductivity, quantity of matter organs, the size of granules ... and also due to the characteristics of the nanoparticle (size, surface area, type of nanoparticle ...) In this work we focus on observing how these nanoparticles (in our case they will be nanoparticles of silver of 77.5 nm in diameter) interact with the ground. We have verified that most of these nanoparticles are retained in the soil and only a small fraction can be recovered once they have been in contact with the ground for one or two weeks. It has been observed that, depending on the type of soil and the experimental procedure followed, these nanoparticles undergo changes in size and some of them are oxidized and passed to the silver ion. One of the parameters that most affect the size and shape of silver is the temperature in the soil sequence. In order to determine these nanoparticles, it will work with technical instruments such as ICP-OES and ICP-MS. In this last one, it works with the unique particle method (SP) in order to be able to distinguish ionic silver from silver in the form of a nanoparticle. In addition, one of the challenges of this work was to be able to determine the size of the nanoparticles. To do this, we had to prepare a spreadsheet, with which we determined the size of the particles, their nanoparticles and their concentration in the number of nanoparticles; the spreadsheet has been validated with 3 nanoparticles of Different3 different sizes