nTiO2 mass transfer and deposition behavior in an aquatic environment

Nano-TiO2 (nTiO(2)) is widely used in industry, and some of it is inevitably released into natural aquatic environments. nTiO(2) can be deposited on the streambed or transported along the stream and streambed, and it can also undergo exchange-transfer processes in these systems. The behavior of nTiO(2) in rivers includes depositiontransfer processes in the stream and exchange-transfer processes between the stream and streambed. In this work, the deposition, mass transfer, exchange, and aggregation behavior of nTiO(2) in a simulated river were studied as a function of the solution pH, stream velocity, and anionic, cationic, and neutral surfactant concentrations. In these experiments, a recirculating flume was used to simulate a natural stream. The nTiO(2) deposition and aggregation phenomena in the river and streambed were characterized. Of the three surfactants studied, the anionic surfactant enhanced the nTiO(2) stability in the river and limited its aggregation most effectively, resulting in slow nTiO(2) deposition and nTiO(2) transport over long distances. This study provides information about nanoparticle transport phenomena in simulated natural aquatic systems.