title: Electrophoresis system for high temperature mobility measurements of nanosize particles.
abstract: The electrophoretic mobility, which reflects the zeta potential of a solid material, is an important experimental quantity providing information about the electrical double layer at the solid/liquid interface. A new high temperature electrophoresis cell was developed suitable for electrophoretic mobility measurements of dispersed nanosize particles up to 150 degrees C and 40 bars. Amorphous silica (SiO(2)) particle size standards were used to test the particle size detection limit of the new instrument at 25, 100, and 150 degrees C and several pH values. The microscopic detection of the particles was enabled by dark-field illumination, which allowed extending the previously available capabilities and provided higher accuracy of the electrophoretic mobility data. The electrophoretic mobility measurements for SiO(2) at temperatures above 100 degrees C were reported for the first time and indicated a gradual increase in particle electrophoretic response with increasing temperature. The obtained data indicated negatively charged SiO(2) surface throughout the pH and temperature ranges studied.
authors.affiliation: Department of Energy and Mineral Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
authors.forename: Victor
authors.initials: V
authors.lastname: Rodriguez-Santiago
authors.forename: Mark V
authors.initials: MV
authors.lastname: Fedkin
authors.forename: Serguei N
authors.initials: SN
authors.lastname: Lvov
mesh_terms: D002138:Calibration; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004867:Equipment Design / Q000295:instrumentation*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D012542:Scattering, Radiation; D012822:Silicon Dioxide / Q000592:standards
chemical_list: D012822:Silicon Dioxide