scholarly journals Modeling and optimization of the photocatalytic degradation of Tartrazine in aqueous solution

2021 ◽  
pp. 133-145
Author(s):  
Mirvet Assassi ◽  
Farid Madjene ◽  
Sara Harchouche ◽  
Hind Boulfiza
Keyword(s):  
Aqueous Solution ◽  
Reaction Time ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Heterogeneous Photocatalysis ◽  
Active Species ◽  
Influential Factor ◽  
Solar Irradiation ◽  
Uv Lamp ◽  
Positive Effect

The application of heterogeneous photocatalysis process using ZnO photocatalyst for the degradation of Tartrazine (TRZ) dye in aqueous solution was investigated in a batch reactor. The estimation, the comparison of the parameter?s effects and the optimization of the removal yield of TRZ were realized by using Box-Behnken experimental design (BBD). The results suggested that the most influential factor on the photocatalytic degradation of the dye was the initial TZR concentration with an effect of (-23.24), the second in the order was the amount of the catalyst with an effect of (+18.09), the third was the reaction time with an effect of (+15.38) and the fourth was stirring speed with a positive effect of (+4.41). The model obtained by BBD led to the following optimal conditions for degradation yield of TRZ: initial concentration of TZR equal to 20.035 mg/L, reaction time equal to 88.635 min, 0.6409 mg/L of ZnO amount and 404.9 rpm for the stirring speed, which gave 98.576% of degradation efficiency. The study of irradiation type effect shows that a solar irradiation gave higher yield than photocatalysis by UV lamp. The O2?- radicals were the principal active species responsible of the degradation of TRZ. The BOD5/COD ratio increased from 0.26 to 0.41 after 60 minutes of photocatalysis under solar light, indicating the feasibility of coupling the photocatalysis process to biological treatment for the removal of TRZ.

Use of Nanopillars-TiO2 Thin Films in the Photocatalytic Degradation of Bromophenol Blue from Aqueous Solution

2018 ◽  
Vol 6 (1) ◽  
pp. 22-30
Author(s):  
C. Lalhriatpuia ◽  
◽  
Thanhming liana ◽  
K. Vanlaldinpuia
Keyword(s):  
Thin Films ◽  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Bromophenol Blue ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

The photocatalytic activity of Nanopillars-TiO2 thin films was assessed in the degradation of Bromophenol blue (BPB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the XRD, SEM and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data showed anatase phase of TiO2 particles with average particle size of 25.4 and 21.9 nm, for S1 and S2 catalysts respectively. The SEM and AFM images indicated the catalyst composed with Nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The average height of the pillars was found to be 180 and 40 nm respectively for the S1 and S2 catalyst. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of BPB using the UV light was studied at wide range of physico-chemical parametric studies to determine the mechanism of degradation as well as the practical applicability of the technique. The batch reactor operations were conducted at varied pH (pH 4.0 to 10.0), BPB initial concentration (1.0 to 20.0 mg/L) and presence of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of BPB. The maximum percent removal of BPB was observed at pH 6.0 and a low initial concentration of the pollutant highly favours the photocatalytic degradation using thin films. The presence of several interfering ions suppressed the photocatalytic activity of thin films to some extent. The time dependence photocatalytic degradation of BPB was demonstrated with the pseudo-first-order rate kinetics. Study was further extended with total organic carbon measurement using the TOC (Total Organic Carbon) analysis. This demonstrated an apparent mineralization of BPB from aqueous solutions.

scholarly journals TiO2 BEADS FOR PHOTOCATALYTIC DEGRADATION OF HUMIC ACID IN PEAT WATER

2011 ◽  
Vol 11 (3) ◽  
pp. 253-257 ◽  
Author(s):  
Winarti Andayani ◽  
Agustin N M Bagyo
Keyword(s):  
Aqueous Solution ◽  
Humic Acid ◽  
Oxalic Acid ◽  
Chemical Oxygen Demand ◽  
Photocatalytic Degradation ◽  
Uv Light ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Color Intensity ◽  
Before And After

Degradation of humic acid in aqueous solution containing TiO2 coated on ceramics beads under irradiation of 254 nm UV light has been conducted in batch reactor. The aim of this experiment was to study photocatalytic degradation of humic acid in peat water. The irradiation of the humic acid in aqueous solution was conducted in various conditions i.e solely uv, in the presence of TiO2-slurry and TiO2 beads. The color intensity, humic acid residue, conductivity and COD (chemical oxygen demand) of the solution were analyzed before and after irradiation.  The compounds produced during photodegradation were identified using HPLC. The results showed that after photocatalytic degradation, the color intensity and the COD value of the solution decreased, while the conductivity of water increased indicating mineralization of the peat water occurred. In addition, oxalic acid as the product of degradation was observed.

Photocatalytic degradation of azo dye in TiO2 suspended solution

2001 ◽  
Vol 43 (2) ◽  
pp. 313-320 ◽  
Author(s):  
C.-H. Hung ◽  
P.-C. Chiang ◽  
C. Yuan ◽  
C.-Y. Chou
Keyword(s):  
Reaction Time ◽  
Light Intensity ◽  
Photocatalytic Degradation ◽  
Azo Dye ◽  
Batch Reactor ◽  
Reaction Rates ◽  
Pseudo First Order Reaction ◽  
Degradation Rates ◽  
Orange G ◽  
Degradation Of Azo Dye

The photocatalysis of azo dye, Orange G, by P-25 anatase TiO2 was investigated in this research. The experiments were conducted in a batch reactor with TiO2 powder suspension. Four near-UV lamps were used as the light source. The experimental variables included solution pH level, amount of TiO2, illumination light intensity, and reaction time. A pseudo-first order reaction kinetic was proposed to simulate the photocatalytic degradation of Orange G in the batch reactor. More than 80% of 10 mg/L Orange G decomposition in 60-minute reaction time was observed in this study and fast decomposition of Orange G only occurred in the presence of both TiO2 and suitable light energy. Faster degradation of Orange G was achieved under acid conditions. The degradation rates of Orange G at pH = 3.0 were about two times faster than those at pH = 7.0. Faster degradation of azo dye was observed for greater irradiated light intensity and more TiO present during the reaction. The reaction rates were proportional to TiO2concentration and light intensity with the power order of 0.726 and 0.734, respectively.

Boron Nitride Doped Polypyrrole Hybrid Composites for Photocatalytic Degradation of 2-Chlorophenol from Aqueous Solution

2020 ◽  
Vol 301 ◽  
pp. 145-152 ◽  
Author(s):  
Faizah Yunus ◽  
Muhammad Syazwan Kassim ◽  
Syed Shahabuddin ◽  
Nur Rahimah Said ◽  
Siti Nor Atika Baharin
Keyword(s):  
Aqueous Solution ◽  
Boron Nitride ◽  
Photocatalytic Degradation ◽  
Hybrid Composites ◽  
Hexagonal Boron Nitride ◽  
Solar Irradiation ◽  
X Ray Diffraction ◽  
Initial Concentration ◽  
Polymerization Method

This investigation focused on the photocatalytic degradation of o2-chlorophenol in aqueous solution by using hexagonal boron nitride (h-BN) doped polypyrrole (PPy) composite under solar irradiation. The composite was prepared via in-situ oxidation polymerization method using FeCl3 as oxidation agent. The synthesized h-BN/PPy composite were comprehensively characterized using x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The photodegradation of 2-chlorophenol was performed under direct sunlight for 180 minutes with initial concentration (50-250 mg/L) and pH (3-9). h-BN/PPy composite efficiently degraded 2-chlorophenol (91.1%) with optimum conditions at pH 6 and 50 mg/L initial concentration compared to PPy and h-BN.

Study on the Photocatalytic Degradation of Diesel Pollutants in Seawater by a Prepared Nano Ag-Droped Zinc Oxide

2014 ◽  
Vol 609-610 ◽  
pp. 311-316
Author(s):  
Xiao Cai Yu ◽  
Dong Dong Hu ◽  
Jin Fang Chen ◽  
Xiao Jie Jin ◽  
Xu Zheng
Keyword(s):  
Reaction Time ◽  
Photocatalytic Degradation ◽  
Calcination Temperature ◽  
Ph Value ◽  
Uv Light ◽  
Removal Rate ◽  
Orthogonal Experiment ◽  
Influential Factors ◽  
Influential Factor ◽  
Sonochemical Method

ZnO and Ag-droped ZnO photocatalysts with different Ag loadings (0.5, 1.0, 1.5, 2.0at%) and different calcination temperature (300, 400, 500, 600, 700°C) were synthesized by a sonochemical method. The morphology and crystal pattern of some prepared catalysts were characterized by XRD and SEM techniques which demonstrated that the prepared catalysts were of hexagonal wurtzite structure. Ag loadings, calcination temperature and other factors, dosage of photocatalyst, reaction time and pH value of seawater, were also taken into consideration in the procedure of photocatalytic degradation reaction under UV light. An orthogonal experiment was carried out to investigate the best combination of factors which can reach the best diesel pollution removal rate and the influence order of factors. Reaction time and dosage of catalyst were the most influential factors in this experiment, and the factor of calcination temperature was the weakest influential factor. The removal rate of diesel can up to 78% when the experiment was undertaken under the very conditions: the dosage of catalyst 2.0g/L, reaction time 2.0h, Ag loading of catalyst 1.0 at%, calcinations temperature 400°C and pH value 8.5.

scholarly journals Photocatalytic Degradation of Acid Yellow 36 Using Zinc Oxide Photocatalyst in Aqueous Media

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Sajjad Khezrianjoo ◽  
Hosakere Doddarevanna Revanasiddappa
Keyword(s):  
Photocatalytic Degradation ◽  
Catalyst Concentration ◽  
Heterogeneous Medium ◽  
Batch Reactor ◽  
Aqueous Media ◽  
Electrical Energy ◽  
Degradation Process ◽  
Active Species ◽  
Catalyst Loading ◽  
Order Of Magnitude

A detailed investigation of photocatalytic degradation of Acid Yellow 36 (AY36) has been carried out in aqueous heterogeneous medium containing ZnO as photocatalyst in a batch reactor. The effects of some parameters such as pH, catalyst loading, and ethanol concentration were examined. Solutions with initial concentration of 50 mg L−1 of dye, within the range of typical concentration in textile wastewaters, were treated at natural pH of 6.93 and catalyst concentration of 1 g L−1 after 180 min irradiation. Investigations on the active species indicated that hydroxyl radicals play the major role in the process. Experiments showed that the most efficient pH on the removal of the dye with photocatalytic degradation process was 8; however, acidic pH was favored for the dark surface adsorption. Electrical energy consumption per order of magnitude for photocatalytic degradation of AY36 has been also determined.

scholarly journals Graphene-Based TiO2 Nanocomposite for Photocatalytic Degradation of Dyes in Aqueous Solution under Solar-Like Radiation

2021 ◽  
Vol 11 (9) ◽  
pp. 3966
Author(s):  
Martina Kocijan ◽  
Lidija Ćurković ◽  
Davor Ljubas ◽  
Katarina Mužina ◽  
Ivana Bačić ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photocatalytic Degradation ◽  
Energy Gap ◽  
Visible Region ◽  
Pure Tio2 ◽  
Solar Irradiation ◽  
Degradation Of Dyes ◽  
Visible Part ◽  
Vis Spectroscopy ◽  
Improved Performance

This study presents a novel method for the development of TiO2/reduced graphene oxide (rGO) nanocomposites for photocatalytic degradation of dyes in an aqueous solution. The synergistic integration of rGO and TiO2, through the formation of Ti–O–C bonds, offers an interesting opportunity to design photocatalyst nanocomposite materials with the maximum absorption shift to the visible region of the spectra, where photodegradation can be activated not only with UV but also with the visible part of natural solar irradiation. TiO2@rGO nanocomposites with different content of rGO have been self-assembled by the hydrothermal method followed by calcination treatment. The morphological and structural analysis of the synthesized photocatalysts was performed by FTIR, XRD, XPS, UV-Vis DRS, SEM/EDX, and Raman spectroscopy. The effectiveness of the synthesized nanocomposites as photocatalysts was examined through the photodegradation of methylene blue (MB) and rhodamine B (RhB) dye under artificial solar-like radiation. The influence of rGO concentration (5 and 15 wt.%) on TiO2 performance for photodegradation of the different dyes was monitored by UV-Vis spectroscopy. The obtained results showed that the synthesized TiO2@rGO nanocomposites significantly increased the decomposition of RhB and MB compared to the synthesized TiO2 photocatalyst. Furthermore, TiO2@rGO nanocomposite with high contents of rGO (15 wt.%) presented an improved performance in photodegradation of MB (98.1%) and RhB (99.8%) after 120 min of exposition to solar-like radiation. These results could be mainly attributed to the decrease of the bandgap of synthesized TiO2@rGO nanocomposites with the increased contents of rGO. Energy gap (Eg) values of nanocomposites are 2.71 eV and 3.03 eV, when pure TiO2 particles have 3.15 eV. These results show the potential of graphene-based TiO2 nanocomposite to be explored as a highly efficient solar light-driven photocatalyst for water purification.

Detoxification of Aqueous Solutions Containing the Commercial Pesticide Metasystox by TiO2-Mediated Solar Photocatalysis

2005 ◽  
Vol 129 (1) ◽  
pp. 74-79 ◽  
Author(s):  
A. Arques ◽  
A. García-Ripoll ◽  
R. Sanchís ◽  
L. Santos-Juanes ◽  
A. M. Amat ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Surface Tension ◽  
Titanium Dioxide ◽  
Active Species ◽  
Test Laboratory ◽  
Solar Irradiation ◽  
Complete Elimination ◽  
Solar Photocatalysis ◽  
Order Of Magnitude ◽  
Commercial Pesticide

A commercial pesticide, namely metasystox, has been chosen to study its detoxification in aqueous solution by means of solar photocatalysis employing titanium dioxide. Initial toxicity/biodegradability has been checked by means of active sludges respirometry and the Zahn–Wellens test. Laboratory scale experiments indicate that significant detoxification (by approximately one order of magnitude) of a 0.05g∕L solution of the active species can be achieved in only 3h of solar irradiation due to the nearly complete elimination of the active compound, methyloxydemeton. In this case, total organic carbon (TOC) measurements cannot be used to evaluate the process as nonactive organic excipients interfere in the measurement. The experiment has been scaled-up to 25L in a solar pilot plant; also in this case more than 75% elimination of methyloxydemeton is achieved in 5h irradiation (∼1400kJ). Besides detoxification (80% initial inhibition of the active sludges and 20% at the end of the experiments), and moderate TOC reduction (∼20%) are observed together with an increase of the surface tension of the solutions, probably due to elimination of excipients having surfactant properties.

Conditions Influencing Struvite Precipitation from Anaerobic Sludge Digestion Filtrate in a Batch Reactor

2011 ◽  
Vol 183-185 ◽  
pp. 1432-1436
Author(s):  
Xiang Sheng Cao ◽  
Xue Zheng Meng ◽  
Yin Zhong Wang
Keyword(s):  
Reaction Time ◽  
Batch Reactor ◽  
Anaerobic Sludge ◽  
Precipitation Process ◽  
Operational Conditions ◽  
Sludge Digestion ◽  
Stirring Rate ◽  
Struvite Precipitation ◽  
Positive Effect ◽  
Sedimentation Time

Struvite precipitation in sludge dewatering filtrate was achieved in a lab-scale sequencing batch reactor. The influence of the operational conditions on the struvite precipitation process has been studied. These operational conditions include stirring rate of the reactor, reaction time and sedimentation time. Experiments indicated that stirring rate of the reactor within 50 rpm to 250 rpm had no strong influence on the formation of struvite. As reaction time increased, there was a slight positive effect on the removal of Mg2+, NH4+ and PO43-. Suggested reaction time is 40-80 minutes based on our experiments. In order to obtain the lower turbidity and the lower PO43- concentration in the decanting filtrate of the batch reactor, the minimum sedimentation time should be more than 30 minutes.

Sign in / Sign up

Export Citation Format

Share Document