Photocatalytic efficiency of titanium dioxide immobilized on PVP/AAc hydrogel membranes: A comparative study for safe disposal of wastewater of Remazol Red RB-133 textile dye

The paper reports on the photocatalytic efficiency ofTiO2nanoparticles immobilized on polyvinyl pyrrolidone/acrylic acid (PVP/AAc) copolymer hydrogels, which are prepared by means ofγ-rays induced homo- and copolymerization. The efficiency of immobilized photocatalyst is tested on a commercial textile dye namely Remazol Red RB-133. The results are compared with photocatalytic efficiencies of different types of non supportedTiO2photocatalysts such as aqueous slurries of colloidalTiO2prepared by sol-gel technique, and commercially available Degussa P25. Although less efficient than nonsupported ones, the hydrogel supportedTiO2photocatalyst has the practical advantages of easy separation and removal from the reactors. This makes it a viable technique for the safe disposal of textile wastewater into the water streams.

Download Full-text

Removal of Remazol Red RR from Aqueous Solution by Glass Supported Films of Synthesized ZnO Nanoparticles

INTERNATIONAL CENTER FOR RESEARCH AND RESOURCE DEVELOPMENT (ICRRD) QUALITY INDEX RESEARCH JOURNAL ◽

10.53272/icrrd.v2i3.2 ◽

2021 ◽

Vol 2 (3) ◽

Author(s):

Mohammad Akter Hossain ◽

Md. Nazmul Kayes ◽

Md. Mufazzal Hossain

Keyword(s):

Aqueous Solution ◽

Removal Efficiency ◽

High Surface ◽

Sol Gel ◽

Volume Ratio ◽

Textile Dye ◽

Sunlight Irradiation ◽

X Ray ◽

Operating Variables ◽

Remazol Red

The nanoparticles of ZnO (n-ZnO) have been synthesized by a sol-gel method and characterized by UV-visible and FTIR spectroscopy, scanning electron microscopy (SEM), energy dispersive X-Ray spectrometry (EDX) and powder X-ray diffractometry (XRD). Precursor of n-ZnO particles were prepared via a non-aqueous route, which was calcined at 500oC. These particles were then deposited on a glass substrate for adsorption and photodegradation of a typical textile dye, Remazol Red R (RRR). Especially, the high surface to volume ratio of nanoparticles has appealed much attention to use these particles both as an adsorbent and a photocatalyst. A comparative study was carried out between n-ZnO and a commercially available ZnO (c-ZnO) to investigate the removal efficiency of RRR from its aqueous solution under different conditions. The removal efficiency has been optimized by varying several operating variables and the highest performance has been obtained with 0.115 g/slide of ZnO and 0.5 × 10-4 M aqueous solution of RRR under sunlight irradiation. It is important to note that the use of the films of ZnO in the presence of solar light makes it suitable for recycling and causes no secondary environmental pollution.

Download Full-text

Influence of some sol-gel synthesis parameters of mesoporous TiO2 on photocatalytic degradation of pollutants

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq150110020g ◽

2016 ◽

Vol 22 (1) ◽

pp. 65-73

Author(s):

Aleksandar Golubovic ◽

Ivana Veljkovic ◽

Maja Scepanovic ◽

Mirjana Grujic-Brojcin ◽

Natasa Tomic ◽

...

Keyword(s):

Anatase Phase ◽

Sol Gel ◽

Tetrabutyl Titanate ◽

Textile Dye ◽

Reactive Orange 16 ◽

Higher Temperature ◽

Tio2 Nanopowders ◽

Gel Technique ◽

Reactive Orange ◽

Sol Gel Synthesis

The titanium dioxide (TiO2) nanopowders were produced by sol-gel technique from tetrabutyl titanate as a precursor by varying some parameters of the sol-gel synthesis like the temperature (500 and 550 ?C) and the duration of the calcination (1.5, 2, and 2.5 h). X-ray powder diffraction (XRPD) results have shown that all synthesized nanopowders are dominantly in anatase phase, with the presence of a small amount of rutile in samples calcined at 550 ?C. According to the results obtained by Williamson-Hall method, the anatase crystallite size was increased with the duration of the calcination (from 24 to 29 nm in samples calcined at lower, and from 30 to 35 nm in samples calcined at higher temperature). The analysis of the shift and linewidth of the most intensive anatase Eg Raman mode confirmed the XRPD results. The analysis of pore structure from nitrogen sorption experimental data described all samples as mesoporous, with mean pore diameters in the range of 5-8 nm. Nanopowder properties have been related to the photocatalytic activity, tested in degradation of the textile dye (C.I. Reactive Orange 16), carbofuran and phenol.

Download Full-text

Fabrication and Measurement of Flexible Polymer Aerogel and Factors Affecting its Thermal Conductivity

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.324.133 ◽

2021 ◽

Vol 324 ◽

pp. 133-138

Author(s):

Jia Zhen Wang ◽

Jing Du ◽

Yun Bo Wang

Keyword(s):

Thermal Conductivity ◽

Sol Gel ◽

Optimal Solution ◽

Factors Affecting ◽

Flexible Polymer ◽

Different Types ◽

Wire Method ◽

High Production ◽

Gel Technique ◽

High Production Cost

Silica aerogels are the most widely studied type of aerogel. However, its application still suffers from low mechanical strength and high production cost. The paper studies the use of recyclable PVC as the backbone material of the aerogel and introduces an economically friendly fabrication process of flexible PVC aerogel using sol-gel technique and ambient drying instead of the CO2 critical drying. Three different types of PVC powder with the molecule weight of 43000, 48000, and 80000 respectively are chosen and dissolved in DMF in five different concentrations-0.2, 0.4, 0.6, 0.8, and 1.0 g (mL)-1. The lowest thermal conductivity of the aerogel is measured using hot-wire method as 0.0323W(m*K)-1, which is made of PVC with molecule weight of 80000 in a concentration of 0.4g (mL)-1. The analysis based on SEM pictures shows that PVC type and concentration would greatly influence aerogel’s structure thus affecting its thermal conductivity. The optimal solution for producing low thermal conductivity aerogel is to use PVC powder with low molecule weight with a concentration between 0.2 and 0.6 g (mL)-1.

Download Full-text

Comparative Study for Photodegradation of Remazol Red R by Different TiO2 Samples

Dhaka University Journal of Science ◽

10.3329/dujs.v65i1.54505 ◽

2017 ◽

Vol 65 (1) ◽

pp. 49-54

Author(s):

Nurnabi Rashed ◽

AZM Mainul Islam Mazumder ◽

Md Mufazzal Hossain

Keyword(s):

Removal Efficiency ◽

Catalyst Concentration ◽

Potassium Dichromate ◽

Light Sources ◽

Photodegradation Efficiency ◽

Different Types ◽

Environmentally Safe ◽

Degussa P25 ◽

Remazol Red ◽

Maximum Removal

Potassium dichromate modified TiO2 photocatalyst (MD-TiO2) was prepared and its photocatalytic activity was compared with that of ordinary commercial TiO2 (C-TiO2) and special Degussa P25 TiO2 (D-TiO2). An organic dye, remozol red R(RRR) was used as a substrate for photodegradation from aqueous solution into environmentally safe products such as water, carbon dioxide and mineral ions. The photodegradation of RRR was carried out by varying the concentration of different types of TiO2 suspension, initial concentrations of dyes between 0.5× 10-4 M and 2.5 ×10-4 M, pH between 2.0 and 6.0 and light sources which are UV, artificial visible and sunlight. With increasing the catalyst concentration, percent degradation was found to increase up to a concentration of 1.2 g/100 mL of C-TiO2, 0.12 g/ 100 mL of D-TiO2 and 0.10 g/100 mL of modified MD-TiO2 for a definite concentration of RRR. However, RRR shows adsorption on TiO2 samples except C-TiO2. Again, the photodegradation efficiency is inversely affected by the dye concentration. Thus, the removal efficiency was found to be influenced by all of the above parameters. The maximum removal efficiency is found at pH 3.0 under sunlight in the presence of modified MD-TiO2,which suggests that MD-TiO2 can be used as an effective material for the removal of RRR instead of C-TiO2 and D-TiO2. Dhaka Univ. J. Sci. 65(1): 49-54, 2017 (January)

Download Full-text

Synthesis of anatase nanopowders by sol-gel method and influence of temperatures of calcination to their photocatalitic properties

Science of Sintering ◽

10.2298/sos1501041g ◽

2015 ◽

Vol 47 (1) ◽

pp. 41-49 ◽

Cited By ~ 1

Author(s):

A. Golubovic ◽

B. Simovic ◽

M. Scepanovic ◽

D. Mijin ◽

A. Matkovic ◽

...

Keyword(s):

Photocatalytic Performance ◽

Anatase Phase ◽

Sol Gel ◽

Tetrabutyl Titanate ◽

Textile Dye ◽

Reactive Orange 16 ◽

Tio2 Nanopowders ◽

Gel Technique ◽

Reactive Orange ◽

Brookite Phase

The titanium dioxide (TiO2) nanopowders were produced by sol-gel technique from tetrabutyl titanate as a precursor, varying the temperature ?f calcination (from 500 to 550?C with the step of 10 ?C). XRPD results have shown that all synthesized nanopowders are dominantly in anatase phase. The analysis of the shift and linewidth of the most intensive anatase Eg Raman mode confirmed the XRPD results and added the presence of small amount of highly disordered brookite phase in all samples. The analysis of pore structure from nitrogen sorption experimental data described all samples as mesoporous, with mean pore diameters in the range of 1.5 and 4.5 nm. Nanopowder properties have been related to the photocatalytic activity, tested in degradation of the textile dye (C.I. Reactive Orange 16). The sample calcined at temperature of 510?C showed the best photocatalytic performance.

Download Full-text

Synthesis, Characterization, and Comparison of Sol–Gel TiO2 Immobilized Photocatalysts

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2012-0054 ◽

2013 ◽

Vol 11 (2) ◽

pp. 633-639

Author(s):

Clara Duca ◽

Gustavo E. Imoberdorf ◽

Madjid Mohseni

Keyword(s):

Photocatalytic Activity ◽

Composite Coatings ◽

Sol Gel ◽

High Photocatalytic Activity ◽

Dichlorophenoxyacetic Acid ◽

Titanium Tetraisopropoxide ◽

Vis Spectroscopy ◽

Degussa P25 ◽

Gel Technique ◽

2,4 Dichlorophenoxyacetic Acid

Abstract This study was focused on the synthesis of titania-based photocatalytic coatings with high photocatalytic activity, attrition resistance, and stability. Five different photocatalytic coatings were synthesized using the sol–gel technique. Three coatings were prepared using aqueous sols of TiO2 nanoparticles with different amounts of titanium tetraisopropoxide and different quantities and types of acids. The other two photocatalysts were composite sol–gel coatings which were prepared by incorporating commercial Degussa P25 into the TiO2 synthesized through sol–gel technique. The physical and optical properties of the immobilized photocatalysts were characterized with UV–vis spectroscopy, X-ray diffraction, scanning electron microscopy, and light scattering. The photocatalytic activity of each coating was determined using a lab-scale differential photoreactor by measuring the degradation rate of a model micropollutant, the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The conversions of 2,4-D obtained with the TiO2 coatings without Degussa P25 were in the order of 7–23%, whereas the two composite coatings provided conversions in the range of 66–69%. In addition, one of the composite coatings showed a more homogeneous morphology and less cracking, and for this reason, it was more durable and showed lower attrition.

Download Full-text

Noble metal modified titania catalysts in the degradation of Reactive Black 5: a kinetic approach

Water Science & Technology ◽

10.2166/wst.2011.524 ◽

2011 ◽

Vol 64 (5) ◽

pp. 1040-1045 ◽

Cited By ~ 8

Author(s):

A. Valentine Rupa ◽

R. Vaithiyanathan ◽

T. Sivakumar

Keyword(s):

Visible Light ◽

Metal Salt ◽

Sol Gel ◽

Industrial Effluent ◽

Kinetic Studies ◽

Economic Feasibility ◽

Reactive Black 5 ◽

Tio2 Catalyst ◽

Degussa P25 ◽

Gel Technique

The photocatalytic degradation of Reactive Black 5 (RB 5), a di-azo dye was investigated over M/TiO2 (M = Ag, Au and Pt) photocatalysts irradiated with UV and visible light. TiO2 was prepared by sol–gel technique (Syn-TiO2). Photodeposition of metal salt precursors over Syn-TiO2 was carried out so as to obtain 1 wt% of M/TiO2 catalysts. The photodecolourization and photodegradation reactions were also compared with commercial TiO2 (Degussa P25) catalyst. Kinetic studies for the decolourization of RB 5 showed that it followed pseudo first order. Recycling of catalysts was performed to check the economic feasibility of the photocatalytic process. In order to check the applicability of M/TiO2 catalyst in the treatment of industrial effluent, real textile effluent was collected from an industry and subjected to photodegradation and the results are presented. Enhanced activity of M/TiO2 catalyst under visible light irradiation highlights its importance in the field of photocatalysis.

Download Full-text