Journal
ENVIRONMENTAL SCIENCE & TECHNOLOGY
Volume 38, Issue 9, Pages 2729-2736Publisher
AMER CHEMICAL SOC
DOI: 10.1021/es034388k
Keywords
-
Categories
Ask authors/readers for more resources
Novel nanostructured porous fibers of self-supported, radially aligned H(2)Ti(8)O(17)(.)1.5H(2)O nanorods were prepared from layered H(2)Ti(4)O(9)(.)1.2H(2)O tetratitanate fibers by novel solvothermal reaction in glycerine at 150-250 degreesC. The H(2)Ti(8)O(17)(.)1.5H(2)O fibers with diameters of 0.5-1.5 mum and lengths of 10-20 mum consist of multi-scale nanopores and nanostructures. They also are of high crystallinity, large surface area of 127 m(2) g(-1), and stable phase up to 350 degreesC. Photocatalytic activity of the H(2)Ti(8)O(17)(.)1.5H(2)O fibers was evaluated in aqueous photooxidation of an azo dye methyl orange in the presence of UV irradiation and O-2, using P-25 as the standard sample. Both the photocatalytic activity and the dispersity-agglomeration property of H(2)Ti(8)O(17)(.)1.5H(2)O fibers are pH-controllable. Highly photooxidative activity, superior to that of P-25, occurs at pH 6.0-11.0 due to certain distinguishable material characteristics and to large amounts of adsorbed reactants of surface active OH. free radicals, surface hydroxyl OH, O-2(.-), (OOH)-O-., and methyl orange. The agglomeration of H(2)Ti(8)O(17)(.)1.5H(2)O fibers becomes more serious from pH 2.0 to pH 5.0 and from pH 6.0 to pH 11.0. Well-dispersed H(2)Ti(8)O(17)(.)1.5H(2)O fibers occur at pH 6.0. Both the total photodegradation of waste chemicals and the entire sedimentation of H(2)Ti(8)O(17)(.)1.5H(2)O fibers can be timed to end simultaneously at suitable pH value. The photocatalyst-free reaction solution is then easily removed, and the fresh wastewater is added again. Standard unit operation processes of chemical engineering are used to design a continuous, low-cost, large-scale, liquid-phase photocatalysis technique based on the H(2)Ti(8)O(17)(.)1.5H(2)O fibers.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available