Scalable synthesis of wrinkled mesoporous titania microspheres with uniform large micron sizes for efficient removal of Cr(VI)

Aerosol-assisted methods possess a strong capability for synthesis of titania (TiO2) microspheres. For dynamic separation applications, rough TiO2 microspheres with uniform large micron sizes, high external-surface-area-to-volume ratios, high surface areas, uniform mesopores and abundant hydroxyl groups are desirable. Herein, we demonstrate the combination of evaporation induced self-assembly (EISA) with a microfluidic-jet spray drying process for scalable synthesis of novel mesoporous TiO2 materials with the above-mentioned properties for Cr(VI) removal under both static and dynamic conditions. The TiO2 materials are spherical with uniform large micron sizes (∼45 μm). They possess wrinkled surfaces and thus have high particle external-surface-area-to-volume ratios. They show high surface areas (22–138 m2 g−1), large pore volumes (0.15–0.27 cm3 g−1) and uniform mesopores (5.2–20.7 nm). They carry abundant surface Ti–OH groups due to the presence of oxygen vacancies and the Ti3+ valence state. Several experimental parameters, such as drying and calcination temperatures, are varied, leading to TiO2 samples with tunable surface areas and mesopore sizes. They can be adopted as batch sorbents for removal of Cr(VI) in water with fast adsorption rates, large capacities and pH-dependent adsorption behavior. Part of the adsorbed Cr(VI) can be reduced to Cr(III) in acidic solutions. The influences of adsorbent properties on adsorption performance are elucidated. Moreover, their uniform large micron sizes make them excellent fillers for efficient separation of Cr(VI) in dynamic flows with similar performance to that under static conditions, as well as easy regeneration and high cycling stability. Their adsorption performance under flowing conditions is much better than those of commercial TiO2 nanoparticles and mesoporous TiO2 materials prepared by a conventional EISA method, which make them very attractive for practical dynamic separation applications.

[1]  Jian Qiang Li,et al.  The MOF+ Technique: A Significant Synergic Effect Enables High Performance Chromate Removal. , 2017, Angewandte Chemie.

[2]  Fang Wang,et al.  Photocatalytic degradation of microcystin-LR with a nanostructured photocatalyst based on upconversion nanoparticles@TiO2 composite under simulated solar lights , 2017, Scientific Reports.

[3]  Ying-hua Liang,et al.  Removal of Cr(VI) by 3D TiO2-graphene hydrogel via adsorption enriched with photocatalytic reduction , 2016 .

[4]  D. Zhao,et al.  Scalable synthesis of mesoporous titania microspheres via spray-drying method. , 2016, Journal of colloid and interface science.

[5]  Ming Dong,et al.  Thioether-Based Fluorescent Covalent Organic Framework for Selective Detection and Facile Removal of Mercury(II). , 2016, Journal of the American Chemical Society.

[6]  G. Han,et al.  Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes. , 2016, Environmental Science and Technology.

[7]  R. Yahya,et al.  The removal of heavy metal ions from wastewater/aqueous solution using polypyrrole-based adsorbents: a review , 2016 .

[8]  S. Luo,et al.  A highly efficient polyampholyte hydrogel sorbent based fixed-bed process for heavy metal removal in actual industrial effluent. , 2016, Water research.

[9]  D. Zhao,et al.  On the improvement of pore accessibility through post-synthesis hydrothermal treatments of spray dried SBA-15 microspheres , 2015 .

[10]  Abdullah M. Al-Enizi,et al.  Radially oriented mesoporous TiO2 microspheres with single-crystal–like anatase walls for high-efficiency optoelectronic devices , 2015, Science Advances.

[11]  Lei Liu,et al.  Black titanium dioxide (TiO2) nanomaterials. , 2015, Chemical Society reviews.

[12]  G. H. Li,et al.  Efficient removal of Cr(VI) from wastewater under sunlight by Fe(II)-doped TiO₂ spherical shell. , 2015, Journal of hazardous materials.

[13]  D. Zhao,et al.  Formation of uniform large SBA-15 microspheres via spray drying , 2014 .

[14]  Hong Liu,et al.  Recent progress in design, synthesis, and applications of one-dimensional TiO2 nanostructured surface heterostructures: a review. , 2014, Chemical Society reviews.

[15]  T. Bein,et al.  Three-dimensional titanium dioxide nanomaterials. , 2014, Chemical reviews.

[16]  Huijun Zhao,et al.  Enhanced photocatalytic activity of hierarchical structure TiO2 hollow spheres with reactive (001) facets for the removal of toxic heavy metal Cr(VI) , 2014 .

[17]  D. Zhao,et al.  Ordered mesoporous black TiO(2) as highly efficient hydrogen evolution photocatalyst. , 2014, Journal of the American Chemical Society.

[18]  Xiaobo Chen,et al.  Titanium dioxide nanomaterials: self-structural modifications. , 2014, Chemical reviews.

[19]  Lixia Sang,et al.  TiO2 nanoparticles as functional building blocks. , 2014, Chemical reviews.

[20]  D. Zhao,et al.  A Perspective on Mesoporous TiO2 Materials , 2014 .

[21]  D. Zhao,et al.  A general "surface-locking" approach toward fast assembly and processing of large-sized, ordered, mesoporous carbon microspheres. , 2013, Angewandte Chemie.

[22]  W. Schuhmann,et al.  TiO2 (B)/anatase composites synthesized by spray drying as high performance negative electrode material in li-ion batteries. , 2013, ChemSusChem.

[23]  Dehong Chen,et al.  Recent Progress in the Synthesis of Spherical Titania Nanostructures and Their Applications , 2013 .

[24]  Inhar Imaz,et al.  A spray-drying strategy for synthesis of nanoscale metal-organic frameworks and their assembly into hollow superstructures. , 2013, Nature chemistry.

[25]  Yanlin Song,et al.  Hierarchical TiO2 photonic crystal spheres prepared by spray drying for highly efficient photocatalysis , 2013 .

[26]  D. Zhao,et al.  Mesoporous titania: From synthesis to application , 2012 .

[27]  Jianfang Wang,et al.  A general approach to mesoporous metal oxide microspheres loaded with noble metal nanoparticles. , 2012, Angewandte Chemie.

[28]  Dehong Chen,et al.  Facile Synthesis of Monodisperse Mesoporous Zirconium Titanium Oxide Microspheres with Varying Compositions and High Surface Areas for Heavy Metal Ion Sequestration , 2012 .

[29]  Ziyu Wu,et al.  Low-cost synthesis of flowerlike α-Fe2O3 nanostructures for heavy metal ion removal: adsorption property and mechanism. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[30]  Lizhi Zhang,et al.  Efficient removal of heavy metal ions with biopolymer template synthesized mesoporous titania beads of hundreds of micrometers size. , 2012, Environmental science & technology.

[31]  D. Zhao,et al.  Assembly of uniform photoluminescent microcomposites using a novel micro‐fluidic‐jet‐spray‐dryer , 2011 .

[32]  Wei Li,et al.  Hydrothermal etching assisted crystallization: a facile route to functional yolk-shell titanate microspheres with ultrathin nanosheets-assembled double shells. , 2011, Journal of the American Chemical Society.

[33]  Xiao Dong Chen,et al.  Microfluidic spray drying as a versatile assembly route of functional particles , 2011 .

[34]  P. Yang,et al.  Templated synthesis of shape-controlled, ordered TiO2 cage structures. , 2011, Small.

[35]  Xiao Dong Chen,et al.  Monodisperse droplet formation through a continuous jet break‐up using glass nozzles operated with piezoelectric pulsation , 2011 .

[36]  K. Suslick,et al.  Porous Carbon Produced in Air: Physicochemical Properties and Stem Cell Engineering , 2011, Advanced materials.

[37]  H. Younesi,et al.  Functionalized SBA-15 mesoporous silica by melamine-based dendrimer amines for adsorptive characteristics of Pb(II), Cu(II) and Cd(II) heavy metal ions in batch and fixed bed column , 2011 .

[38]  D. Zhao,et al.  Ordered mesoporous materials as adsorbents. , 2011, Chemical communications.

[39]  Yuying（黄宇营） Huang,et al.  Arsenic removal and recovery from copper smelting wastewater using TiO2. , 2010, Environmental science & technology.

[40]  G. Stucky,et al.  High performance separation of aerosol sprayed mesoporous TiO2 sub-microspheres from aggregates via density gradient centrifugation , 2010 .

[41]  D. Zhao,et al.  Comprehensive study of pore evolution, mesostructural stability, and simultaneous surface functionalization of ordered mesoporous carbon (FDU-15) by wet oxidation as a promising adsorbent. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[42]  Fuzhi Huang,et al.  Mesoporous Anatase TiO2 Beads with High Surface Areas and Controllable Pore Sizes: A Superior Candidate for High‐Performance Dye‐Sensitized Solar Cells , 2009 .

[43]  Colin Hills,et al.  Precipitation of heavy metals from wastewater using simulated flue gas: sequent additions of fly ash, lime and carbon dioxide. , 2009, Water research.

[44]  Arnold J. Forman,et al.  A general route to diverse mesoporous metal oxide submicrospheres with highly crystalline frameworks. , 2008, Angewandte Chemie.

[45]  C. Majumder,et al.  Novel biofiltration methods for the treatment of heavy metals from industrial wastewater. , 2008, Journal of hazardous materials.

[46]  Reinhard Vehring,et al.  Pharmaceutical Particle Engineering via Spray Drying , 2007, Pharmaceutical Research.

[47]  D. Zhao,et al.  Controllable and repeatable synthesis of thermally stable anatase nanocrystal-silica composites with highly ordered hexagonal mesostructures. , 2007, Journal of the American Chemical Society.

[48]  Xiaobo Chen,et al.  Titanium dioxide nanomaterials: synthesis, properties, modifications, and applications. , 2007, Chemical reviews.

[49]  E. Ilton,et al.  Cr(VI) removal from aqueous solution by activated carbon coated with quaternized poly(4-vinylpyridine). , 2007, Environmental science & technology.

[50]  F. Iskandar,et al.  Enhanced Photocatalytic Performance of Brookite TiO2 Macroporous Particles Prepared by Spray Drying with Colloidal Templating , 2007 .

[51]  U. Pal,et al.  Size-Controlled Synthesis of Spherical TiO2 Nanoparticles: Morphology, Crystallization, and Phase Transition , 2007 .

[52]  Xiao Dong Chen,et al.  Air drying of milk droplet under constant and time‐dependent conditions , 2005 .

[53]  Hajime Haneda,et al.  Visible-Light-Driven N−F−Codoped TiO2 Photocatalysts. 1. Synthesis by Spray Pyrolysis and Surface Characterization , 2005 .

[54]  Galo J. A. A. Soler-Illia,et al.  Fundamentals of Mesostructuring Through Evaporation‐Induced Self‐Assembly , 2004 .

[55]  M. Antonietti,et al.  Synthesis of very small TiO2 nanocrystals in a room-temperature ionic liquid and their self-assembly toward mesoporous spherical aggregates. , 2003, Journal of the American Chemical Society.

[56]  D. Zhao,et al.  Self-adjusted synthesis of ordered stable mesoporous minerals by acid–base pairs , 2003, Nature materials.

[57]  Galo J. A. A. Soler-Illia,et al.  Nanocrystalline Transition‐Metal Oxide Spheres with Controlled Multi‐Scale Porosity , 2003 .

[58]  Justin C. Lytle,et al.  Hybrid macroporous materials for heavy metal ion adsorption , 2002 .

[59]  Mohammed M. Farid,et al.  Adsorption kinetics for the removal of chromium(VI) from aqueous solution by adsorbents derived from used tyres and sawdust , 2001 .

[60]  Younan Xia,et al.  Preparation of Mesoscale Hollow Spheres of TiO2 and SnO2 by Templating Against Crystalline Arrays of Polystyrene Beads , 2000 .

[61]  Yunfeng Lu,et al.  Aerosol-assisted self-assembly of mesostructured spherical nanoparticles , 1999, Nature.

[62]  Bradley F. Chmelka,et al.  Generalized syntheses of large-pore mesoporous metal oxides with semicrystalline frameworks , 1998, Nature.

[63]  O. M. Kut,et al.  TiO2-Assisted Degradation of Environmentally Relevant Organic Compounds in Wastewater Using a Novel Fluidized Bed Photoreactor , 1996 .