表面活性剂对纳米TiO_2在水中分散与沉降性能的影响

Dispersion and deposition of the aqueous suspensions of TiO_2 nanoparticles in the presence of surfactant

研究了不同表面活性剂对纳米TiO2在水中分散行为及沉降行为的影响,并从理论上加以解释.采用紫外分光光度计测定了纳米TiO2的吸光度,采用纳米粒度仪测定了粉体的表面Zeta电位.结果表明:表面活性剂十六烷基三甲基氯化铵、十二烷基苯磺酸钠和吐温80都增大了纳米TiO2在水体中的分散性.十六烷基三甲基氯化铵和十二烷基苯磺酸钠对纳米TiO2的分散机理是改变了粉体表面的Zeta电位,从而增大了粒子之间的排斥力,使溶液能够稳定存在,减少了纳米TiO2的沉降率;吐温80对纳米TiO2的分散机理是吐温80能够明显降低水的表面张力,因此空间稳定作用相对明显.

The dispersion and deposition of the aqueous suspensions of TiO2 nanoparticles were studied in the presence of surfactant, and the experimental results were explained in theory. The absorbance of TiO2 nanoparticles was measured using Uv spectrophotometer, the zeta potential of TiO2 nanoparticles was measured using Malvern Instruments. It shows that hexadecyltrimethylammonium chloride, sodium dodecyl benzene sulfonate and tween 80 enhanced the dispersion behavior of TiO2 nanoparticles in aqueous solutions. The mechanism of the hexadecyltrimethylammonium chloride and sodium dodecyl benzene sulfonate dispersing TiO2 nanoparticles is that the changes in the zeta potential of TiO2 nanoparticles surface consequently enhances the repulsive force of TiO2 nanoparticles, stabilitates the aqueous suspensions, and decreases the deposition of TiO2 nanoparticles in the aqueous suspensions; The mechanism of the twain 80 scattering nanometer TiO2 is that the twain 80 can significantly reduce the surface tension of the water, so the stabilization of space is obviously increased.