Effect of nickel sulphate and magnesium sulphate on pH of sulphuric acid solutions at elevated temperatures

被引：5

作者：

Jankovic, Z. ^{[1
]}

Papangelakis, V. G. ^{[1
]}

Lvov, S. N. ^{[2
]}

机构：

[1] Univ Toronto, Dept Chem Engn & Appl Chem, Toronto, ON M5S 3E5, Canada

[2] Penn State Univ, Dept Energy & Mineral Engn, University Pk, PA 16802 USA

来源：

JOURNAL OF APPLIED ELECTROCHEMISTRY | 2009年 / 39卷 / 06期

基金：

加拿大自然科学与工程研究理事会;

关键词：

High-temperature pH measurement; Yttria-stabilized zirconia sensor; 250; DEGREES-C; AQUEOUS-SOLUTIONS; 250-DEGREES-C; SPECIATION; LATERITES; SENSORS;

D O I：

10.1007/s10800-008-9719-8

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

A flow-through potentiometric technique utilizing an yttria-stabilized zirconia (YSZ) pH sensor has been employed to elucidate the effects of NiSO4 and MgSO4 on pH of H2SO4 solutions at temperatures of 200 A degrees C and 250 A degrees C. Solution pH was found to increase with increasing NiSO4 and MgSO4 concentrations at both temperatures. This trend is attributed to the dissociation of NiSO4 and MgSO4 where the SO4 (2-)(aq) released reacts with H+(aq) to form HSO4 (-)(aq). The conversion of measured potentials into pH values was based on the mixed-solvent electrolyte (MSE) model, which is a speciation model of the new OLI Systems(A (R)) software. Both the Henderson equation and exact definition of the diffusion potential were employed in treating the obtained experimental data. Experimental pH values calculated using the diffusion potentials evaluated by either approach are similar, suggesting that the Henderson equation can be effectively used. In addition, LiCl was found to be a suitable alternative to NaCl as the reference electrode solution.

引用

页码：751 / 759

页数：9

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