scholarly journals Water-Active Titanium/Molybdenum/Mixed-Oxides: Removal Efficiency of Organic Water Pollutants by Adsorption and Photocatalysis and Toxicity Assessment

Catalysts ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1054
Author(s):  
Tamara B. Ivetić ◽  
Nina L. Finčur ◽  
Daniela V. Šojić Merkulov ◽  
Vesna N. Despotović ◽  
Dragana D. Četojević-Simin ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Removal Efficiency ◽  
Uv Irradiation ◽  
Mixed Oxides ◽  
Hepatoma Cell ◽  
Degradation Efficiency ◽  
Hepatoma Cell Line ◽  
Simulated Sunlight ◽  
Microstructural Investigation ◽  
Vis Spectroscopy

A new titanium/molybdenum/mixed-oxides (TMO) contact-type heterojunction photocatalyst was prepared by a simple, low-cost, and environmentally-friendly mixing-calcination solid-state method. A microstructural investigation by scanning electron microscopy (SEM) showsirregularly shaped agglomerated morphology of TMO that consists of firmly connected globular TiO2 and rod-like MoO3 particles. The detailed structure and optical bandgap investigation by X-ray diffraction, Raman, and UV-Vis spectroscopy revealed the TMO’s composition of ~37 wt.% rutile TiO2, ~25 wt.% of anatase TiO2, and ~38 wt.% of molybdite MoO3 phase and an absorption threshold of around 380 nm, which implies more probability of desirable higher visible light absorption. The removal efficiency of pesticides quinmerac (QUI) and tembotrione (TEM), and pharmaceuticals metoprolol (MET), amitriptyline (AMI), ciprofloxacin (CIP),and ceftriaxone (CEF) from water in the presence of starting pure TiO2, MoO3, and prepared TMO were investigated under different pH values and UV irradiation/simulated sunlight (SS). Each starting metal-oxide precursors and prepared TMO showed a different affinity for adsorption of tested pesticides and pharmaceuticals, and, in general, better photocatalytic degradation efficiency under UV irradiation than under simulated sunlight. The highest photocatalytic degradation efficiency under UV irradiation was 81.6% for TEM using TMO; using TiO2 was 65.0% for AMI, and using MoO3 was 79.3% for CEF after 135 min. However, TMO showed a very high synergic adsorption/photocatalytic under-SS efficiency in the removal of CIP of almost 80% and under UV irradiation of 90% CIP removal after 75 min. The toxicity of catalysts, starting compounds, and their intermediates formed during the removal process was assessed using a rat hepatoma cell line (H-4-II-E). The highest hepatotoxic effects were obtained by using UV irradiated QUI and MET suspension with TMO for up to 60 min.

scholarly journals Photo-Transformation of Effluent Organic Matter by ZnO-Based Sunlight Irradiation

2020 ◽  
Vol 10 (24) ◽  
pp. 9002
Author(s):  
Thao Thi Nguyen ◽  
Seong Nam Nam ◽  
Jeill Oh
Keyword(s):  
Organic Matter ◽  
Photocatalytic Degradation ◽  
Removal Efficiency ◽  
Treatment Plant ◽  
Wastewater Effluent ◽  
Solar Irradiation ◽  
Effluent Organic Matter ◽  
Sunlight Irradiation ◽  
Vis Spectroscopy ◽  
The Impact

This study investigated the impact of effluent organic matter (EfOM) from wastewater effluent on the properties of organic matter in receiving water and the efficiency of its removal using photocatalysis. The organic matter is characterized using fluorescence excitation-emission matrices coupled with parallel factor analysis (EEM-PARAFAC), UV-Vis spectroscopy, and dissolved organic carbon (DOC) measurements. The experiments are conducted with water samples that were collected from upstream waters (used as a source of dissolved organic matter (DOM)), wastewater effluent (a source of EfOM), and waters downstream of a wastewater treatment plant, and with upstream water and wastewater effluent being mixed at different ratios in the lab (DOM/EfOM). EEM-PARAFAC analysis identifies three components: a humic-like component (C1), a tyrosine-like component (C2), and a terrestrial-like humic component (C3). When compared to DOM, EfOM has a higher specific ultraviolet absorbance at 254 nm (SUVA254), a higher fluorescence index (FI), and more abundant humic-like components. As the EfOM contribution increased, an increase in both humic-like components and a simultaneous decrease in the protein-like components are observed. The photocatalytic degradation of the organic matter using simulated solar irradiation with ZnO as a catalyst is examined. The removal efficiency of photocatalysis is calculated using the DOC, UV absorbance at 254 nm (UV254), and the maximum fluorescence intensity (Fmax) of the PARAFAC components. After 120 min of irradiation, the removal efficiency of photocatalysis differs between the DOM, EfOM, and EfOM-impacted samples due to the change in the properties of the organic matter in the source water. The photocatalytic degradation of organic matter follows pseudo-first-order kinetics, with the DOC and UV254 exhibiting a lower removal efficiency with the increasing contribution of EfOM, which indicated that EfOM has a potentially negative impact on the performance of drinking water treatment. The removal of PARAFAC components follows the order C3 > C1 > C2, indicating that humic-like components are preferentially removed when compared to protein-like components under sunlight irradiation.

scholarly journals Experimental study on photocatalytic degradation efficiency of mixed crystal nano-TiO2 concrete

2020 ◽  
Vol 9 (1) ◽  
pp. 219-229 ◽  
Author(s):  
Zhan Guo ◽  
Chenxiang Huang ◽  
Yu Chen
Keyword(s):  
Photocatalytic Degradation ◽  
Uv Irradiation ◽  
Mixed Crystal ◽  
Influential Factors ◽  
Degradation Efficiency ◽  
Experimental Results ◽  
Pollutant Concentration ◽  
Solar Irradiation ◽  
Irradiation Condition ◽  
Spraying Method

AbstractThe photocatalytic mixed crystal nano-TiO2 particles were incorporated with concrete by means of the internal doping method (IDM) and spraying method (SPM) in this paper. To evaluate the photocatalytic degradation efficiency of mixed crystal nano-TiO2 concrete, the methyl orange (MO) was chosen to simulate pollutants. The physicochemical characteristics and photocatalytic performance of mixed crystal nano-TiO2 concrete prepared by above two different methods were experimentally investigated under UV irradiation and solar irradiation. Furthermore, the effects of two key influential factors including pollutant concentration and irradiation condition were also analyzed and discussed. Experimental results indicate that the nano-TiO2 concrete prepared by the spraying method (SPM) exhibits maximum photocatalytic degradation efficiency of 73.82% when the sprayed nano-TiO2 slurry concentration is 10mg/L. The photocatalytic degradation efficiency of unpolished nano-TiO2 concrete is much higher than that of polished nano-TiO2 concrete under the same exposure time of UV irradiation. Moreover, the photocatalytic degradation efficiency of nano-TiO2 concrete decreases with the increase of pollutant concentration. The irradiation condition has an obvious influence on the photocatalytic degradation efficiency of nano-TiO2 concrete. In the aspect of applications, the practical recommendations for the nano-TiO2 concrete with self-cleaning capacity were presented according to the experimental results.

Photocatalytic degradation of leather dye over ZnO catalyst supported on alumina and glass surfaces

2001 ◽  
Vol 44 (5) ◽  
pp. 211-218 ◽  
Author(s):  
S. Sakthivel ◽  
B. Neppolian ◽  
M. Palanichamy ◽  
B. Arabindoo ◽  
V. Murugesan
Keyword(s):  
Photocatalytic Degradation ◽  
High Performance ◽  
Degradation Efficiency ◽  
Dye Molecules ◽  
Adsorption Behaviour ◽  
Fenton Reagent ◽  
High Concentration ◽  
Operational Conditions ◽  
Vis Spectroscopy ◽  
Glass Surfaces

The photocatalytic degradation of leather dye, Acid green 16, has been investigated over a ZnO catalyst supported on two different materials, namely alumina and glass beads (3-5 mm diameter). Sunlight was used as the energy source. The alumina-supported ZnO outperformed the glass-supported ZnO under identical operational conditions suggesting that the dye molecules are adsorbed on the alumina supports to make a high concentration environment around the loaded ZnO. The degradation efficiency was greater at pH = 4 compared to other acidic and neutral pH. Also, the degradation efficiency was a little bit higher in alkaline medium, which correlates with the adsorption behaviour of acid green 16 on the alumina supported ZnO. The influence of inorganic oxidants like H2O2, FeCl3 and Fenton reagent on the degradation efficiency were systematically studied. The decolourisation and extent of degradation of the dye were determined by UV-VIS spectroscopy and COD reflux methods, respectively. Complete mineralisation of the dye was conformed by High performance liquid chromatography (HPLC) analysis.

Effect of UV irradiation on aflatoxin reduction: a cytotoxicity evaluation study using human hepatoma cell line

2017 ◽  
Vol 33 (4) ◽  
pp. 343-350 ◽  
Author(s):  
Ankit Patras ◽  
Sharath Julakanti ◽  
Sudheer Yannam ◽  
Rishipal R. Bansode ◽  
Mallory Burns ◽  
...  
Keyword(s):  
Cell Line ◽  
Uv Irradiation ◽  
Hepatoma Cell ◽  
Evaluation Study ◽  
Hepatoma Cell Line ◽  
Human Hepatoma ◽  
Human Hepatoma Cell ◽  
Human Hepatoma Cell Line

scholarly journals Effect of ball milling process on the photocatalytic performance of CdS/TiO2 composite

2020 ◽  
Vol 9 (1) ◽  
pp. 558-567 ◽  
Author(s):  
Mengya Ye ◽  
Jiahui Pan ◽  
Zhan Guo ◽  
Xiaoyu Liu ◽  
Yu Chen
Keyword(s):  
High Temperature ◽  
Photocatalytic Degradation ◽  
Ball Milling ◽  
Uv Irradiation ◽  
Photocatalytic Performance ◽  
Milling Process ◽  
Degradation Efficiency ◽  
Ball Milling Process ◽  
Composite Photocatalysts ◽  
High Temperature Calcination

AbstractCdS/TiO2 composite photocatalysts were made by the method of secondary ball milling at different ball milling speeds, milling time, and material ratios. After the secondary ball milling process, parts of the samples were calcined at high temperatures. X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectroscopy (DRS) were used to observe the powder particle size, structural defect, bandgap, and absorption spectrum of the samples. Combined with the observation results, the effects of ball milling speed, time, material ratio, and high-temperature calcination on the photocatalytic performance of CdS/TiO2 composite samples were analyzed. Furthermore, the methyl orange (MO) was chosen to simulate pollutants, and the photocatalytic degradation rate of CdS/TiO2 composite photocatalysts for MO was evaluated under sunlight and UV irradiation conditions. The photocatalytic degradation efficiency of CdS/TiO2 photocatalyst under UV irradiation is much higher than that under sunlight irradiation. The experimental results reveal that secondary ball milling can effectively promote the formation of CdS/TiO2 composite nanostructure and the high-temperature calcination can reduce the bandgap width, which makes the samples easier to be excited. When the ball milling speed, time, and material ratio were respectively 400 rpm, 10 h, 25:75, and then calcined at high temperature, after 2 h of irradiation under UV light, CdS/TiO2 composite photocatalysts exhibited maximum photocatalytic degradation efficiency of 57.84%.

Endothelial Cell Protein S Synthesis Is Upregulated by the Complex of IL-6 and Soluble IL-6 Receptor

1997 ◽  
Vol 77 (05) ◽  
pp. 1014-1019 ◽  
Author(s):  
W Craig Hooper ◽  
Donald J Phillips ◽  
Bruce L Evatt
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Line ◽  
Neutralizing Antibodies ◽  
Hepatoma Cell ◽  
Protein S ◽  
Oncostatin M ◽  
Cell Protein ◽  
Microvascular Endothelial Cell ◽  
Hepatoma Cell Line

SummaryWe have recently demonstrated that the proinflammatory cytokine, interleukin-6 (IL-6), could upregulate the production of protein S in the human hepatoma cell line, HepG-2, but not in endothelial cells. In this study, we have demonstrated that the combination of exogenous IL-6 and soluble IL-6 receptor (sIL-6R) could significantly upregulate protein S production in both primary human umbilical vein endothelial cells (HUVEC) and in the immortalized human microvascular endothelial cell line, HMEC-1. The IL-6/sIL-6R complex was also able to rapidly induce tyrosine phosphorylation of the IL-6 transducer, gpl30. Neutralizing antibodies directed against either IL-6 or gpl30 blocked protein S upregulation by the IL-6/sIL-6R complex. It was also observed that exogenous sIL-6R could also upregulate protein S by forming a complex with IL-6 constitutively produced by the endothelial cell. Two other cytokines which also utilize the gpl30 receptor, oncostatin M (OSM) and leukemia inhibitory factor (LIF), were also able to upregulate endothelial cell protein S. This study demonstrates a mechanism that allows endothelial cells to respond to IL-6 and also illustrates the potential importance of circulating soluble receptors in the regulation of the anticoagulation pathway.

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