کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4482655 1316865 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Arsenic sorption on TiO2 nanoparticles: Size and crystallinity effects
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
پیش نمایش صفحه اول مقاله
Arsenic sorption on TiO2 nanoparticles: Size and crystallinity effects
چکیده انگلیسی

Single solute As (III) and As (V) sorption on nano-sized amorphous and crystalline TiO2 was investigated to determine: size and crystallinity effects on arsenic sorption capacities, possible As (III) oxidation, and the nature of surface complexes. Amorphous and crystalline nanoparticles were prepared using sol-gel synthesis techniques. For amorphous TiO2, solute pH in the range of 4–9 had a profound impact on only As (V) sorption. As (III) and As (V) sorption isotherms indicated that sorption capacities of the different TiO2 polymorphs were dependent on the sorption site density, surface area (particle size) and crystalline structure. When normalized to surface area, As (III) surface coverage on the TiO2 surface remained almost constant for particles between 5 and 20 nm. However, As (V) surface coverage increased with the degree of crystallinity. X-ray absorption spectroscopic analysis provided evidence of partial As (III) oxidation on amorphous TiO2 rather than crystalline TiO2. The data also indicated that As (III) and As (V) form binuclear bidentate inner-sphere complexes with amorphous TiO2 at neutral pH.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Water Research - Volume 44, Issue 3, February 2010, Pages 965–973
نویسندگان
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