CAJ | 학술논문

研究了不同电解质(NaCl、CaCl2、KCl、K2SO4和 K2CrO4)对氧化铁纳米颗粒(Fe2O3NP)聚集作用的影响,并用聚集效率来衡量聚集作用变化,用DLVO理论对各因素的影响进行解释.实验表明：浓度和价态的升高会显著增强NP的聚集作用；阴离子对NP聚集作用的影响强于阳离子(以KCl为对照,K2SO4引起了比CaCl2更显著的变化)；K2CrO4的影响显著大于其他离子(0.5mmol/L的K2CrO4即可引起剧烈的聚集).通过DLVO理论发现：离子在较低浓度增长或价态的上升,会同时降低ζ电位和双电层厚度以促进聚集作用；阴离子和K2CrO4较阳离子,会更显著地降低ζ电位,从而加速聚集作用；浓度在较高区间变化时ζ电位相对稳定,此时双电层的压缩是促进聚集作用的主要原因.
연구료불동전해질(NaCl、CaCl2、KCl、K2SO4화 K2CrO4)대양화철납미과립(Fe2O3NP)취집작용적영향,병용취집효솔래형량취집작용변화,용DLVO이론대각인소적영향진행해석.실험표명：농도화개태적승고회현저증강NP적취집작용；음리자대NP취집작용적영향강우양리자(이KCl위대조,K2SO4인기료비CaCl2경현저적변화)；K2CrO4적영향현저대우기타리자(0.5mmol/L적K2CrO4즉가인기극렬적취집).통과DLVO이론발현：리자재교저농도증장혹개태적상승,회동시강저ζ전위화쌍전층후도이촉진취집작용；음리자화K2CrO4교양리자,회경현저지강저ζ전위,종이가속취집작용；농도재교고구간변화시ζ전위상대은정,차시쌍전층적압축시촉진취집작용적주요원인.
Influences of electrolytes (NaCl, CaCl2, KCl, K2SO4 and K2CrO4) on the hematite nanoparticle (Fe2O3NP) aggregation were investigated. The attachment efficiency (α) was applied to assess the alternations of aggregation behavior, and the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was utilized to elucidate the mechanisms underlying the observed changes. Results clearly showed that the aggregation behaviors were enhanced by electrolytes of higher valence and/or at higher concentration;anions exhibited greater effects on the aggregation of NPs than cations (e.g., K2SO4 had induced more significant aggregation than CaCl2 as comparing to KCl);K2CrO4 could enhance the aggregation more significantly than other electrolytes (0.5 mmol/L of K2CrO4 could induce great aggregation). Based on the DLVO theory, we suggested that increasing the concentration (within a relatively low range) and valence of electrolytes would promote the aggregation by decreasing the zeta potential (ζ) and the Debye length simultaneously;the greater impacts of anions and K2CrO4 on aggregation of NPs comparing to the cations were mainly induced by the dramaticall decrease ofζ;theζwould remain relatively steady within relatively high concentration ranges of electrolytes, whereas the reduction of Debye length would become the key factor in promoting aggregation behaviors.