scholarly journals Electrolytic Cell Applied for the Breakdown of Endocrine Disrupting Drugs in Aqueous Tributaries

2020 ◽  
Author(s):  
Jorge Alberto Mendoza Pérez ◽  
Abril Gardenia Martínez Castillo ◽  
Jorge Octaviano Gomez Castrejon ◽  
Juan Carlos Gómez Buendía
Keyword(s):  
Titanium Dioxide ◽  
Aqueous Media ◽  
Potassium Hydroxide Solution ◽  
Oxygen Demand ◽  
Polar Compounds ◽  
Electrolytic Cell ◽  
Synthetic Wastewater ◽  
Alkaline Salt ◽  
Endocrine Disrupting ◽  
Layer Chromatography

In this chapter, we report previous results about advances of an electrolysis process developed for breakdown of endocrine disrupting drugs in aqueous media. The objective is to achieve the breakdown of two drugs: trimethoprim and a mixture of clavulanic acid-amoxicillin (1:7) with an electrolytic cell by means of oxidization-reduction reactions. The evaluation of the process was carried out using spectrometry techniques UV-Vis, thin layer chromatography (TLC), chemical oxygen demand (COD), and total organic carbon (TOC). Handcrafted mineral carbon electrodes doped with titanium dioxide were designed, platinum and copper wires were placed, and a potassium hydroxide solution was used as electrolyte. The electrolyte, being an alkaline salt, allows the transport of charges from one side to the other, and electrode doped with titanium dioxide is used in order to help the electronic transfer, and the mineral carbon, having a strong affinity for organic and non-polar compounds, performs an adsorption process. Results from several performed assays showed that after 1 hour of treatment, it can be seen the breakdown of the drugs present in a synthetic wastewater solution.

Bioremediation of synthetic fatliquors under microaerobic condition

2016 ◽  
Vol 75 (5) ◽  
pp. 1118-1127 ◽  
Author(s):  
B. Umamaheswari ◽  
K. Priya ◽  
Rama Rajaram
Keyword(s):  
Oxygen Demand ◽  
Polar Compounds ◽  
Industrial Applications ◽  
Gas Chromatography Mass Spectrometry ◽  
Microaerobic Condition ◽  
Wide Range ◽  
End Products ◽  
Emulsifying Agent ◽  
Microaerobic Conditions ◽  
Layer Chromatography

Synthetic fatliquors are useful as a fatliquoring agent, flotation agent and emulsifying agent in a wide range of industrial applications such as leather, pharmacy and farm chemicals. These fatliquors remain recalcitrant to natural biota in existing treatment plants. In the present study, the isolated microaerophilic Serratia sp. HA1 strain CSMB3 is capable of utilizing structurally different fatliquors as the sole substrate for their growth under microaerobic conditions. Degradation of vegetable fatliquors was observed from 95 to 97% in terms of lipids, with the production of lipase at 72 h. Degradation of synthetic fatliquors was observed in terms of chemical oxygen demand from 85% to a minimum of 25%. It is in the order of sulfited/sulfated fatliquors > sulfochlorinated fatliquors > chlorinated fatliquors. A thin layer chromatography chromatogram confirmed the degradation of non polar fatliquor to polar compounds. Production of the red pigment prodigiosin in synthetic fatliquors enhanced the growth of the isolate. Fourier transform infrared spectroscopy (FTIR) confirmed the bioremediation of sulfochlorinated fatliquor into lipids and fatty acids and gas chromatography–mass spectrometry (GC-MS) results confirmed that alcohols and esters are the final end products. Thus the isolated strain CSMB3 may be used in the treatment of wastewaters containing vegetable and synthetic fatliquors.

Effect of Dispersant on the Measurement of Particle Size Distribution of Titanium Dioxide

2012 ◽  
Vol 512-515 ◽  
pp. 261-264
Author(s):  
Li Shen ◽  
Jin Hu ◽  
Da Ping Wu
Keyword(s):  
Particle Size ◽  
Titanium Dioxide ◽  
Zeta Potential ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Anionic Surfactant ◽  
Sodium Sulfate ◽  
Aqueous Media ◽  
Rutile Tio2 ◽  
Tio2 Particles

As anionic surfactant, a commercial salt of lauryl sodium sulfate was used. The effects of different amounts of dispersant on the measurement of particle size distribution between two titanium dioxide powders (anatase and rutile) in aqueous media were discussed. Diluted aqueous suspensions were characterized in terms of particle size distribution and zeta potential. The results demonstrate that the measurement of particle size distribution strongly depends on the amounts of dispersant. The amounts of dispersant have a significant effect on the behavior of the rutile-TiO2 particles. The particle size first decreases significantly with an increase in the amounts of dispersant and then lesser increases with a further increase in the amounts of dispersant. The tendency show significant differences between two particles.

scholarly journals Treatment of low strength wastewater using compact submerged aerobic fixed film (SAFF) reactor filled with high specific surface area synthetic media

2019 ◽  
Vol 80 (4) ◽  
pp. 737-746
Author(s):  
Rishi Gurjar ◽  
Akshay D. Shende ◽  
Girish R. Pophali
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Synthetic Wastewater ◽  
Utilization Rate ◽  
Kinetic Coefficients ◽  
Fixed Film ◽  
Synthetic Media

Abstract Studies on laboratory-scale submerged aerobic fixed film reactor (SAFF) packed with synthetic media having specific surface area of 165 m2/m3 with a void volume of 89% were carried out to assess its performance under various organic loading rates (OLR) and hydraulic retention times (HRT). Synthetic wastewater having chemical oxygen demand (COD) and biochemical oxygen demand (BOD) of 400 ± 10% and 210 ± 10% mg/L respectively was fed and the reactor was subjected to OLRs ranging from 0.37 to 1.26 kg COD/m3.d. It was observed that steady sloughing of biofilm occurs within the SAFF reactor all the times and average concentration of sloughed biomass in the effluent was 26 mg/L. The COD and BOD removal efficiencies varied between 85 and 89% and 86 to 94%, respectively. The kinetic studies demonstrated that SAFF reactor followed Stover–Kincannon and Grau models, with high correlation coefficients (R2) of 0.9977 and 0.9916, respectively. Thus, the values of kinetic coefficients such as maximum substrate utilization rate, Umax = 64.1 g/(L.d); saturation value constant, KB = 72.31 g/(L.d) and Grau second-order substrate removal rate constant, Ks = 2.44 day−1 can be useful to develop and design large scale SAFF reactors. Finally, the study reveals that the optimum range for OLR can vary within 0.68–0.94 kg COD/m3.d.

scholarly journals Enhanced Photocatalytic Degradation of Caffeine Using Titanium Dioxide Photocatalyst Immobilized on Circular Glass Sheets under Ultraviolet C Irradiation

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 964
Author(s):  
Rattana Muangmora ◽  
Patiya Kemacheevakul ◽  
Patiparn Punyapalakul ◽  
Surawut Chuangchote
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Degradation ◽  
Tio2 Film ◽  
Irradiation Time ◽  
Anatase Phase ◽  
Treated Wastewater ◽  
Synthetic Wastewater ◽  
Coated Glass ◽  
Caffeine Degradation ◽  
Ultraviolet C

This work presents the development of titanium dioxide (TiO2) film immobilized on circular glass sheets for photocatalytic degradation of caffeine under ultraviolet C (UVC) irradiation. TiO2 was synthesized through the ultrasonic-assisted sol–gel method and immobilized on circular glass sheets by the doctor blade technique. Polyvinylpyrrolidone (PVP) was used to mix with the TiO2 precursor solution to enhance film adhesion on the glass surface. TiO2 film was mainly composed of anatase phase with a small amount of rutile phase. Caffeine removal was found to increase with increasing irradiation time. Caffeine (20 mg/L) in the synthetic wastewater could not be detected after 3 h of UVC irradiation. The reaction rate of caffeine degradation followed the pseudo-first-order model. The concentrated caffeine solutions required a longer irradiation time for degradation. The used TiO2-coated glass sheets could be easily separated from the treated wastewater and reusable. The caffeine removal efficiency of TiO2-coated glass sheets in each cycle maintained a high level (~100%) during fifteen consecutive cycles.

scholarly journals Assessing local materials for the treatment of wastewater in open drains

2019 ◽  
Vol 79 (5) ◽  
pp. 895-904 ◽  
Author(s):  
Priyanka Jamwal ◽  
Daniel Phillips ◽  
Kim Karlsrud
Keyword(s):  
Organic Matter ◽  
Removal Efficiency ◽  
Green Infrastructure ◽  
Low Cost ◽  
Oxygen Demand ◽  
Synthetic Wastewater ◽  
Significant Difference ◽  
Biological Contaminants ◽  
Local Materials ◽  
Aggregate Material

Abstract In the present study, three low-cost filter aggregate materials were tested and compared for organic matter and fecal coliform (FC) removal at the laboratory scale. Setups were subjected to synthetic wastewater at two hydraulic loading rates (HLR), i.e. 4 cm/day and 40 cm/day. The hydraulic retention time (HRT) at the two HLRs varied from 4 days to 12 h, respectively. The result obtained shows that the biochemical oxygen demand (BOD5) removal efficiency of aggregate materials decreased with the increase in HLR. Both at high and low HLR, the terracotta aggregate material exhibited maximum BOD5 loading removal and without significant difference for the case of FC removal efficiency for all the three aggregate materials. At higher HLR, cell debris and biofilm loss from the aggregate material contributed to the chemical oxygen demand (COD) levels in the treated water. The terracotta aggregate material provided best organic matter removal at both HLRs. The study demonstrates the potential of incorporating inexpensive and readily available local materials into decentralized, frugal green infrastructure interventions capable of lowering the quantum of harmful biological contaminants in open storm water channels in rapidly urbanizing cities of developing countries, and that the terracotta aggregate material provided best organic removal at both HLRs.

Biodegradation of aniline

1997 ◽  
Vol 36 (10) ◽  
pp. 53-63 ◽  
Author(s):  
Shabbir H. Gheewala ◽  
Ajit P. Annachhatre
Keyword(s):  
Activated Sludge ◽  
Ammonia Oxidation ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Inhibitory Effect ◽  
Synthetic Wastewater ◽  
Nitrifying Bacteria ◽  
Aquatic Life ◽  
Oxidation Rates ◽  
Batch Tests

Discharge of aniline to the environment must be controlled as aniline is toxic to aquatic life and also exerts additional oxygen demand due to nitrification reaction involved during its biodegradation. Organic carbonaceous removal by heterotrophs during aniline biodegradation releases NH4+ which is the substrate for autotrophic nitrifying bacteria. However, aniline is toxic to nitrifying bacteria and severely inhibits their activity. Accordingly, batch and continuous studies were conducted to assess the biodegradation of aniline and its inhibitory effect on nitrification. Synthetic wastewater was used as feed with aniline as sole carbon source for mixed microbial population. Experiments were conducted at ambient temperatures of 30–32°C. An aerobic activated sludge Unit was operated at an HRT of about 13 hours and SRT of about 12 days. Biomass from aerobic activated sludge process treating domestic wastewater was acclimatized to synthetic wastewater Containing aniline. Removal efficiencies more than 95% were obtained for feed aniline concentrations upto 350 mg/l with insignificant inhibition of nitrification due to aniline. Ammonia oxidation rates of about 20–115 mgNH4N/l/d were observed. Batch tests were carried out to test the inhibitory effects of high initial aniline concentrations on nitritication. Carbonaceous removal by heterotrophs proceeded rapidly within 4–6 hours with nitrification picking up as soon as aniline concentration dropped below 3–4 mg/l. For higher initial aniline concentration more than 250 mg/l, complete nitrification did not take place even after aniline Concentration dropped below 3–4 mg/l.

Electrochemical incineration of vinasse in filter-press-type FM01-LC reactor using 3D BDD electrode

2008 ◽  
Vol 58 (12) ◽  
pp. 2413-2419 ◽  
Author(s):  
J. L. Nava ◽  
A. Recéndiz ◽  
J. C. Acosta ◽  
I. González
Keyword(s):  
Aqueous Media ◽  
Three Dimensional ◽  
Oxygen Demand ◽  
Electrochemical Reactor ◽  
Filter Press ◽  
Boron Doped Diamond ◽  
Diamond Electrode ◽  
Boron Doped ◽  
Boron Doped Diamond Electrode ◽  
Electrochemical Incineration

This work shows results obtained in the electrochemical incineration of a synthetic vinasse with initial chemical oxygen demand (COD) of 75.096 g L−1 in aqueous media (which resembles vinasse industrial wastewater). Electrolyses in a filter-press-type FM01-LC electrochemical reactor equipped with a three-dimensional (3D) boron doped diamond electrode (BDD) were performed at Reynolds values between 22 ≤ Re ≤ 109, and a fixed current density of 10 mA cm−2. The electrochemical incineration achieved up to 97% in vinasse mineralization with current efficiencies that surpass unity and energy consumption of 168 KW-h m−3, at Re =109. The mineralization of vinasse indicates that such degradation occurs via hydroxyl radicals formed by the oxidation of water on the BDD surface. Experimental data revealed that hydrodynamic conditions slightly influence the vinasse degradation rate and current efficiency, indicating that the oxidation involves a complex pathway.

Preparation, Characterization and Photocatalytic Application of Carbonate Modified Titania

2013 ◽  
Vol 764 ◽  
pp. 219-235
Author(s):  
Rita Sandeep Dhodapkar ◽  
Nageswara Rao Neti
Keyword(s):  
Titanium Dioxide ◽  
Catalytic Activity ◽  
Pollution Abatement ◽  
Oxygen Demand ◽  
Binding Energies ◽  
Advanced Technology ◽  
Oh Radicals ◽  
Oh Groups ◽  
Adsorption Sites ◽  
Photocatalytic Application

Carbonate is a common pollutant in water and wastewater. A study to understand its influence on the photodegradation rates is necessary especially when TiO2/UV technique is emerging as an advanced technology for pollution abatement. In the present investigation, we report surface modification of titanium dioxide using carbonate ions, characterization of carbonate modified titanium dioxide (CMT) and photocatalytic application of carbonate modified TiO2. Titanium dioxide from two different sources namely BDH, Mumbai and Degussa AG, Germany was used as photocatalyst. The CMT catalysts were characterized using potentiometry, FT-IR and XPS. Approximately, 18.9 mg CO3/g CMT(BDH) and 8.13 mg CO3/g CMT(Degussa) was found loaded as determined by potentiometry. The C 1s and O 1s binding energies observed at 289.2 and 531.3 eV, respectively were attributed to surface carbonate species. The adsorption and photodegradation of Acid Blue I dye examined using neat TiO2 as well as CMT catalysts revealed that carbonate inhibits catalytic activity for color and Chemical Oxygen Demand (COD) removal. The photo degradation rate constant (k, s-1) decreases gradually with increasing concentration of carbonate. Thus, in the absence of carbonate kdye is 5.45 × 10-4 s-1 (R2 = 0.97) and kCOD is 3.50 × 10-5 s-1 (R2 = 0.97). At 100 mg/L CO32-, kdye is 0.16 × 10-4 s-1 (R2 = 0.96) and kCOD is 2.66 × 10-5 s-1 (R2 = 0.98). In addition, the carbonate spiking studies revealed the onset of inhibition soon after the addition of carbonate into reacting suspensions of TiO2. The results suggest that carbonate inhibits catalytic activity through formation of strong surface complex under suitable pH by displacing OH2+ and OH groups from TiO2 surface. This results not only in fewer (OH)surface groups available for h+ trapping for oxidation into OH radicals but also in non-availability of adsorption sites for the dye molecules. A pretreatment to remove carbonate from (waste) water appears necessary prior to application of TiO2/UV technique

Pharmaceutical Removal from Synthetic Wastewater Using Heterogeneous - Photocatalyst

2015 ◽  
Vol 802 ◽  
pp. 507-512 ◽  
Author(s):  
Chee Mei Lee ◽  
Puganeshwary Palaniandy ◽  
Nastaein Qamaruz Zaman ◽  
Mohd Nordin Adlan
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Degradation ◽  
Degradation Rate ◽  
Treatment Process ◽  
Treatment Method ◽  
Synthetic Wastewater ◽  
Optimum Ph ◽  
Pharmaceutical Removal ◽  
Ph Range ◽  
Very High

Compound Parabolic Collecting Reactor (CPCR) was designed and used for the heterogeneous-photocatalytic treatment process. Sunray was act as an economically and ecologically sensible light source. The photocatalytic degradation of paracetamol in the synthetic wastewater by using titanium dioxide (TiO2) was investigated. The experimental results show that the paracetamol removal rates were very high and nearly equal (97.2% to 99.7%) at pH 4-7 and TiO2 concentration of 0.5-1 g/L. This implies that the photocatalytic degradation rate of paracetamol is not affected by pH range in this study as the electrostatic interaction between the TiO2 and paracetamol is not able to be developed unless a wider range of pH is set. Furthermore, the concentration of TiO2 of 0.5 g/L is too high to treat the concentration of 10 mg/L of paracetamol. Further research is needed in order to identify the optimum pH condition and a suitable correlation of concentration between TiO2 and paracetamol. Finally, the results proved that the heterogeneous-photocatalyst treatment method which associated with the application of CPCR and solar energy is able to eliminate the paracetamol from the synthetic wastewater.

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