摘要
通过探索不同背景溶液(NaNO_3)浓度及磷浓度下纳米二氧化钛(nTiO_2)表面Zeta电位的变化,研究了不同流速对nTiO_2颗粒和磷酸盐迁移的影响。结果表明:在pH为6.5时,随着NaNO_3浓度的增加,nTiO_2颗粒表面的Zeta负电位也随之降低。在磷酸盐存在下,nTiO_2颗粒表面的负电位随着磷酸盐浓度增加而增强。因此,nTiO_2颗粒在低NaNO_3浓度和高磷酸盐浓度下时具有较好的弥散稳定性。石英砂柱迁移实验证明了水流速度越大nTiO_2颗粒的迁移率就越大,可溶性磷酸盐的迁移量也增多。两点动力学吸附模型可以很好的模拟迁移穿透曲线。模型结果表明,随着流速的增加,导致位点2吸附效率(k_2)、解析效率(k_(2d))以及位点1吸附效率(k_1)值越小,nTiO_2颗粒在石英砂上的吸附效率越低、滞留越少、其迁移性也就越高。
We studied Zeta potentials of nanoparticles titanium dioxides(nTiO2)in different concentration of NaNO3and phosphate(P)solutions.In addition,the effect of flow rate on the transport of nTiO2in P was investigated at pH=6.5.Experimental results show that the Zeta potential of nTiO2is compressed with the increasing ion concentration(IC)of NaNO3at pH=6.5.The negative charge increases with the augment of P.Therefore,the high P and low NaNO3induce the stabilization of nTiO2aggregates.The transport experiments suggest that the rapid flow rate is favorable for the transportability of nTiO2and soluble phosphate.The breakthrough transport curves(BTCs)of nTiO2in sand columns can be fitted well with two-site kinetic attachment model.The modeling results suggest that the values of first-order attachment rate coefficients(k2)and detachment rate coefficients(k2d)on site2and first-order attachment rate coefficients(k1)on site1are responsible to the attaching efficiency of nTiO2on sands and their transportability.
作者
冯刚
徐楠
李祖玲
曹玉和
孙可青
FENG Gang;XU Nan;LI Zuling;CAO Yuhe;SUN Keqing(School of Chemistry,Biology and Material Engineering,SUST,Suzhou 215009,China;Jiangsu Key Laboratory of Environmental Functional Material,Suzhou 215009,China)
出处
《苏州科技大学学报（自然科学版）》
CAS
2018年第1期56-61,70,共7页
Journal of Suzhou University of Science and Technology（Natural Science Edition）
基金
国家自然科学基金面上研究项目(21377090)
