Enhanced Photocatalytic Degradation of Antibiotic and Hydrogen Production by Iron Doped Cerium(IV) Oxide

2021 ◽  
Vol 21 (5) ◽  
pp. 3099-3106
Author(s):  
Yang Hsu ◽  
Joy Thomas ◽  
Chang Tang Chang ◽  
Chih Ming Ma

Norfloxacin (NF) is an emerging antibiotic contaminant due to its significant accumulation in the environment. Photocatalytic degradation is an effective method for removing emerging contaminant compounds in aqueous solution; however, it is not commonly applied because of the poor solubility of contaminant compounds in water. In this study, a photocatalytic degradation experiment was carried out on NF using a self-made ceria catalyst. At an initial concentration of NF of 2.5 mg L−1, the dosage of CeO2 was 0.1 g L−1 photocatalyst in water, and the initial pH of the NF solution was 8.0. With a reaction time of 180 min, the total removal rate of NF could reach 95%. Additionally, the studies on hydrogen production show that the maximum hydrogen production with 2% Fe–CeO2 can reach 25,670 μmol h−1 g−1 under close to 8 W of 365 nm, a methanol concentration of 20%, and a catalyst dose of 0.1 g L−1 photocatalyst in water. Furthermore, the intensities of photoluminescence (PL) emission peaks decreased with increased Fe-doped amounts on CeO2, suggesting that the irradiative recombination seemed to be weakened.

2012 ◽  
Vol 476-478 ◽  
pp. 2005-2008
Author(s):  
Xiu Hua Zhu ◽  
Jia Huan Liu ◽  
Li Li Zhao ◽  
Peng Yuan Wang

Environmental friendly materials, K6SiW11O39SnⅡ(abbreviated as SiWSn), was synthesized, which is visible light response photocatalyst. The photocatalytic decomposition of Acid Brilliant Scarlet (abbreviated as ABS) aqueous solution with SiWSn was investigated using a broad spectrum of solar radiation. The results showed that the photocatalytic degradation efficiency of ABS with SiWSn was affected by the initial pH of ABS solution, the amount of SiWSn and the photolysis time. When the initial pH of ABS solution was 5, the initial concentration of that (20mL) was 3mg L-1, the concentration of SiWSn was 1.25g L-1, and it was irradiated 4h under the sunlight, the discoloration rate of which was 71.4%.


2012 ◽  
Vol 433-440 ◽  
pp. 172-177 ◽  
Author(s):  
Chen Zhong Jia ◽  
Qiao Yan Qin ◽  
Yan Xin Wang ◽  
Cai Xiang Zhang

Photocatalytic degradation of bisphenol A in aqueous solution by UV-TiO2 was studied in self-made photocatalysis reactor. The results showed that BPA was degraded effectively in UV-TiO2 photocatalysis system, and the processe followed Langmuir-Hinshelwood kinetic model. When TiO2 was dosed at 1.0 g/L, air amount was 1.2 L/min, BPA initial concentration was 10 mg/L with pH=5.5, and irradiated by a 15 W low pressure mercury vapor discharge lamp, the removal rate of BPA was up to 97%, and BPA was completely removed in 80 min when pH≥9.5; The photocatalytic removal rate constant was strongly related to the above factors.


2014 ◽  
Vol 1010-1012 ◽  
pp. 523-527
Author(s):  
Ya Mei Wen ◽  
Hong Hui Teng

Brewing spent diatomite (BSDT), a beer industrial by-product, was used for the adsorptive removal of copper ions from an aqueous solution. The results show that The removal rate of Cu2+decreased from 67.2% to 2.8% with decreasing initial pH from 6 to 2; the adsorption capacity decreased proportionally with an increasing amount of BSDT-800, but the removal efficiency of Cu2+increased with an increasing amount of adsorbent; the adsorption uptake at equilibrium (qe) increases from 9.9 mg/g to 34.1 mg/g with increasing initial concentration from 10 mg/L to 50 mg/L at 293K; the adsorption process of Cu2+onto BSDT-800 can be described by second-order reaction kinetics.


2018 ◽  
Vol 6 (1) ◽  
pp. 22-30
Author(s):  
C. Lalhriatpuia ◽  
◽  
Thanhming liana ◽  
K. Vanlaldinpuia

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.


2020 ◽  
Vol 301 ◽  
pp. 145-152 ◽  
Author(s):  
Faizah Yunus ◽  
Muhammad Syazwan Kassim ◽  
Syed Shahabuddin ◽  
Nur Rahimah Said ◽  
Siti Nor Atika Baharin

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.


2013 ◽  
Vol 634-638 ◽  
pp. 280-285 ◽  
Author(s):  
Lin Deng ◽  
Bing Huang ◽  
Huai Yuan Zhao ◽  
Jia Yao Du ◽  
Ling Gao

A new immobilization microorganism (IM) method was built by adding sodium alginate, SiO2 and CaCO3 in gel and cross-linking with saturated H3BO3 aqueous solution with 2% CaCl2 for traditional PVA-H3BO3 method. The modified method was used for preparation IM for hydrogen production from waste water contained organics by sewage treatment plants’ sludge pretreated. The change rate of the IM balls diameter and unit hydrogen production were taken as the primary performance criterion of the IM. The modified IM method for hydrogen production from waste water contained organics was confirmed: 9% PVA and 0.9% sodium alginate for the embedding medium, saturated H3BO3 aqueous solution and 2% CaCl2 for cross-linking agent, and adding NaCO3 adjusting PH, 3%SiO2 and 0.5%CaCO3 for the support packing of IM balls, and the balls diameter of about 3mm. The modified IM balls had unit hydrogen production of 63.3% and total sugar removal rate of 143.4mL/h•L for washing model wastewater from ice cream factory, which contained 2000 mg/L total sugar and 5500mg/L COD, and higher mechanical strength. It were identified that the method could reduce outside surface’s shrink, and improve the homogeneous of inside endoporus structure of modified IM balls, and a similar inside microporosity and outside microporosity by SEM detection.


2011 ◽  
Vol 183-185 ◽  
pp. 1378-1382 ◽  
Author(s):  
Qing Dong Qin ◽  
Jun Ma ◽  
Da Fang Fu

All-silica zeolite beta (BEA) was tested for the ability to remove nitrobenzene and benzoic acid from aqueous solution. The effect of contact time, temperature, initial concentration and initial pH were investigated in a batch reactor system. Adsorption of nitrobenzene decreased with increase in temperature. The equilibrium isotherm was L-shaped. Nitrobenzene adsorption was independent of pH. Adsorption of benzoic acid increased with increasing temperature from 5 °C to 22 °C and decreased with increasing temperature from 22°C to 32 °C. The equilibrium isotherm was approximately S-shaped. Benzoic acid adsorption was dependent of pH. At pH8.0, benzoic acid can also be adsorbed effectively. The results above confirmed that BEA had the potential to be utilized as relatively effective adsorbent for nitrobenzene and benzoic acid removal.


2013 ◽  
Vol 764 ◽  
pp. 284-292 ◽  
Author(s):  
Jaimin Vyas ◽  
Manish Mishra ◽  
Vimal Gandhi

The photocatalytic degradation (PCD) of three commercially textile dyes, namely Alizarin Cyanine Green G (ACG), Reactive Red 195 (RR195) and Reactive Black 5 (RB5) has been investigated using TiO2(Degussa P25) photocatalyst in aqueous solution under UV light. Experiments were conducted to optimize various parameters viz. amount of catalyst, initial concentration of dye and solution pH. Degradation of all the dyes was examined by using UV spectrophotometer. Photocatalytic degradation increased with increasing TiO2loading (in the range 0.51.5 g/L) and decreasing with increasing dye concentration (in the range 20-100 mg/L) and solution pH (in the range 4-10). Result demonstrated that the reactivity of the three dyes for TiO2catalyzed PCD was as follows: Reactive Red 195>Reactive Black 5>Alizarin cyanine Green G, respectively.


2012 ◽  
Vol 476-478 ◽  
pp. 1926-1929
Author(s):  
Xiao Cai Yu ◽  
Dong Dong Hu ◽  
Qian Du ◽  
Xv Zheng ◽  
Ji Yao Guo

Nanoscale titanium dioxide (TiO2) has been fabricated through a sound sol-gel method at room temperature with Tetra-n-butyl Titanate as the precursor, and the particles are characterized by XRD and TEM techniques. The results manifest that the as-prepared TiO2 is amorphous with the anatase structure and its size is around 33.2nm. Five factors, including dosage of TiO2, initial concentration of diesel, pH value, photocatalytic degradation reaction time and the presence of H2O2, are considered in the diesel degradation experiments. An orthogonal test is carried out to optimize the photocatalytic degradation of diesel pollutants based on the single-factor experiments. It reveals that when the dosage of TiO2 is 1.0g/L, the initial concentration of diesel is 0.5g/L, pH value is 6, the reaction time is 4h and the H2O2 dosage is 0.09%, the removal rate of diesel pollutants can up to 88%. Besides, the influence of each factor on removing diesel can be arranged in decreasing order: initial concentration of diesel> photocatalytic reaction time> pH value> TiO2 dosage> H2O2 dosage.


2013 ◽  
Vol 15 (4) ◽  
pp. 494-503 ◽  

<p>The performance of a laboratory scale electrocoagulation system for the removal of Cr and Ni from model wastewater was studied systematically using iron and aluminum electrodes with an effective surface area of 13.8 cm2 and a distance of 4 cm. The influence of several parameters, such as initial concentration, electrode combination, current supply and initial pH was investigated during electrocoagulation process. The increase in initial concentration favored removal rate, did not affect nickel removal, but restricted chromium removal, thus indicating its required mechanism of reducing hexavalent ion to trivalent. The best removal efficiency, when metals existed separately in treated solutions, was accomplished with the use of iron electrodes for Cr (50%) and with aluminum electrodes for Ni (90%). When metals co-existed, iron electrodes achieved the best result, which was 76% for Cr and 82% for Ni, leaving 30 mg l-1 and 17 mg l-1 of residual concentrations, respectively, after 180 min of treatment. Solutions&rsquo; nominal pH appeared to be optimal, since increasing or decreasing their initial value did not benefit the electrocoagulation process. Chromium and nickel simultaneous removal was best achieved for conditions of 100 mg l-1 initial concentration, pH 5 and a current of 0.8 A.</p>


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