SOME UNIQUE CHARACTERISTICS OF CHROMATE ION-EXCHANGE

被引：24

作者：

SENGUPTA, AK

CLIFFORD, D

机构：

[1] Univ of Houston, Houston, TX, USA, Univ of Houston, Houston, TX, USA

来源：

REACTIVE POLYMERS | 1986年 / 4卷 / 02期

关键词：

Ion exchange resins - Polystyrenes;

D O I：

10.1016/0167-6989(86)90007-3

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

Some unique characteristics of chromate ion exchange at acidic pH are presented. Binary chromate isotherms with sulfate or chloride as the competing species show inflection points due to the presence of Cr//2O//7**2** minus in the exchanger phase along with HCrO//4** minus . The positive curvature preceding such inflection points causes early gradual Cr(VI) breakthrough during column runs even when instantaneous equilibrium is assumed. Polystyrene ion-exchange resins offer higher chromate selectivity than polyacrylic ones; increased moisture content and close proximity of the neighboring ion-exchange sites are prime reasons for the polyacrylic resins' inferior chromate selectivity.

引用

页码：113 / 130

页数：18

共 25 条

[1]

Arden T.V., 1961, J APPL CHEM, V11, P229

[2]

BONNER OD, 1967, J AM CHEM SOC, V61, P326

[3] TERMODYNAMIC QUANTITIES IN EXCHANGE OF ZINC WITH SODIUM IONS IN VARIOUSLY CROSS-LINKED POLYSTYRENE SULFONATE CATION EXCHANGERS AT 25 DEGREES [J].