Potentiometric titration of hematite and magnetite at elevated temperatures using a ZrO₂-based pH probe

详细信息    查看全文

• 作者：H.R. Zebardast ; M. Pawlik ; S. Rogak ; E. Asselin
• 关键词：Potentiometric titration ; Fouling ; Magnetite ; Hematite
• 刊名：Colloids and Surfaces A: Physicochemical and Engineering Aspects
• 出版年：5 March, 2014
• 年：2014
• 卷：444
• 期：Complete
• 页码：144-152
• 全文大小：2010 K

文摘

Potentiometric titration using a high temperature and high pressure ZrO₂ based pH probe connected to an external pressure balanced reference electrode (EPBRE) was employed to measure the surface charge and point of zero charge (PZC) of magnetite and hematite colloids at temperatures up to 200 掳C. Background-corrected titration data for magnetite and hematite particles were obtained in NaClO₄ solutions at ionic strengths of 0.1 and 0.01 which permitted the approximate estimation of PZC using the inflection point of the titration plots (pH_infl). When temperature increased from 100 掳C to 200 掳C, the pH_infl for magnetite and hematite decreased from 6.08 卤 0.1 to 4.84 卤 0.1 and 7.17 卤 0.1 to 5.74 卤 0.1, respectively.