Synthesis, characterization, and adsorption kinetics of titania nanotubes for basic dye wastewater treatment

Abstract

Titanium dioxide has been recognized as an excellent photocatalyst material applied on many fields especially for environmental science or engineering. However, the effect of acid washing treatment on the morphology or phase and pore structures of titania nanotubes (TNs) has not still been clearly investigated. The variation of morphology, formation mechanism, phase structure, and pore structure of TN were thus characterized with FE-SEM, TEM, XRD, and N 2 BET isotherms, respectively in the present work. Titania nanotube synthesized via a simple hydrothermal chemical process formed a crystalline structure with open-ended and multiwall morphologies. The XRD patterns and N 2 BET isotherms implied that the acid washing techniques could improve the TN surface area and the pore size distribution up to 292 m 2 g −1 and 40-60 nm, respectively. According to EXAFS/XANES spectra, the structure of the TN is closer to the anatase specimen and much more correlated with octahedral structure. Effects of the pore structure variation on basic dye (Basic Green 5 (BG5)) adsorption by TN were discussed in the present work. Moreover, the adsorption ability, mechanisms, and kinetics of BG5 dye onto TN were also examined with the aid of model analyses of the adsorption equilibrium and kinetic data. Therefore, the potential of TN for the removal of BG5 dye contaminant from wastewaters implied that further development would be warranted.

Insight into the adsorption mechanism of cationic dye onto biosorbents derived from agricultural wastes

“…Furthermore, we also compared the SBET and Q o max of MG5 adsorption onto the biosorbents in this study with those of the other adsorbents in the previous literature (Table 8). Theses adsorbents comprised hydrochar (Tran et al, 2017g), biochar (Tran et al, 2017c), non-spherical activated carbon (Shiau and Pan, 2005;Tran et al, 2017b;Tran et al, 2017f), spherical activated carbon (Huang et al, 2014;Tran et al, 2017a), silver nanoparticles-loaded activated carbon (Ag-NP-AC) and zinc oxide nanorods-loaded activated carbon (ZnONR-AC) (Ghaedi et al, 2014), mesoporous zeolite (MCM-41) (Lee et al, 2007), glucose hydrochar modified with 1% triethylenetetramine (GH-TETA1%) and activated carbon modified with 1% triethylenetetramine (GAC1%) (Tran et al, 2017a), montmorillonite and activated clay (Shiau and Pan, 2005), titania nanotube (Lin et al, 2010). The difference on the Q o max values between these adsorbents might result from different primary adsorption mechanisms.…”

Preparation of Photoactive Tungsten-doped Anatase Nanotubes Using Hydrothermal Technique

“…The precipitates were neutralized thoroughly with HCl, then washed with deionized water, filtered and dried at 100°C. The detailed procedure is reported elsewhere (15,16) .…”

Optimization of phenoxazinone synthase production by response surface methodology and its application in Congo red decolourization

“…Traditional technologies for wastewater treatment have been proved to be ineffective to treat wastewaters contaminated with various synthetic dyes. To solve the problem, several specific treatments have been evaluated to remove synthetic dyes from wastewater (Forgacs et al 2004) including adsorption (Namasivayam et al 1994;Santhy and Selvapathy, 2006;Lin et al 2010), chemical oxidation (Qiu et al 2005), photocatalysis (Hachem et al 2001;Kuo and Ho, 2001), biological decolourization (Pearcea et al 2003;Selvam and Shanmuga Priya, 2012), and processes using combination treatment (Ghoreishi and Haghighi, 2003;Papić et al 2004;Tantak and Chaudhari, 2006;Matveevich et al 2009). However, the applications of these methods on a large scale were prohibited by high cost, limited applicability, and generation of toxic byproducts that were environmentally harmful.…”