改性钙基蒙脱石酸性条件下吸附油酸钠

为脱除选矿废水中油酸根,研究了钙基蒙脱石和十六烷基三甲基溴化铵改性钙基蒙脱石在pH2+、Al3+反应的标准自由能变化ΔG0与pH的关系。结果表明,pH2+、Al3+与油酸根化学吸附的标准自由能变化ΔG0具有较大负值,化学吸附具有自发趋势。

Sodium oleate adsorption by modified Ca-montmorillonite under acid condition

Using Ca-montmorillonite and hexadecyl trimethyl ammonium bromide modified Ca-montmorillonite to adsorb sodium oleate in simulation flotation wastewater under pH value less than 6.5, in order to remove C17H32COO- in the flotation wastewater. The different adsorption products under different adsorption conditions were studied by infrared spectrum test, also, the microstructure of Ca-montmorillonite and modified montmorillonite absorbed by C17H32COO- were observed through scanning electron microscope, the relationship between standard Gibbs free energy change ΔG0, pH value of the reaction of oleate and Ca2+, Al3+ was explained by thermodynamics. The results show that under the condition of pH value less than 6.5, the chemical adsorption of C17H32COO- can exist in the surface of Ca-montmorillonite and modified Ca-montmorillonite plates, and as the form of oleic acid molecules and indissolvable oleate, the corresponding maximum adsorption rate at the pH value of 3 and 5 are 75.15%, 95.82%, respectively,and the corresponding adsorption capacities are 17.83 and 22.73 mmol/100 g. The ΔG0 negative value of the reaction of oleate and Ca2+, Al3+ in the montmorillonite plates is much larger, and the chemical adsorption has spontaneous tendency.