scholarly journals Coupled Oxides/LLDPE Composites for Textile Effluent Treatment: Effect of Neem and PVA Stabilization

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 394
Author(s):  
Norfatehah Basiron ◽  
Srimala Sreekantan ◽  
Lim Jit Kang ◽  
Hazizan Md Akil ◽  
Rabiatul Basria S.M.N. Mydin

The polyvinyl alcohol (PVA) and neem extract were grafted onto coupled oxides (3ZT-CO) via reflux process to stabilize the particles to form 3ZT-CO/PVA and 3ZT-CO/Neem. These were then incorporated into LLDPE by melt blending process to give LLDPE/3ZT-CO/PVA and LLDPE/3ZT-CO/Neem composites. The Neem and PVA stabilized particles showed high zeta potential and dispersed homogeneously in water. The stabilization process altered the shape of the particles due to plane growth along the (002) polar direction. The stabilizers acted as capping agents and initiated the one-dimensional growth. The alkyl chain groups from PVA increased the polarity of the LLDPE/3ZT-CO/PVA and played a dominant role in the water adsorption process to activate the photocatalytic activity. This was further enhanced by the homogeneous distribution of the particles and low degree of crystallinity (20.87%) of the LLDPE composites. LLDPE/3ZT-CO/PVA exhibited the highest photodegradation (93.95%), which was better than the non-stabilized particles. Therefore, the photocatalytic activity of a polymer composite can be enhanced by grafting PVA and neem onto couple oxides. The LLDPE/3ZT-CO/PVA composite was further used to treat textile effluent. The results showed the composite was able to remove dye color by 93.95% and to reduce biochemical oxygen demand (BOD) and chemical oxygen demand (COD) by 99.99%.

2020 ◽  
Vol 17 (35) ◽  
pp. 507-523
Author(s):  
Marina COMINOTE ◽  
Gabriel Libardi SILVA ◽  
Netalianne Mitchelle Fagundes HERINGER ◽  
Faiçal GAZEL ◽  
Renato César de Souza OLIVEIRA

Electroflocculation is a technique for liquid effluent treatment that has been widely used due to simplicity in operation and to the possibility of application in different types of effluents. This study aimed to evaluate the electroflocculation treatment efficiency, monitoring and controlling an effluent automatically from the textile industry, also considering a feasibility study to photovoltaic generation application. The electrofloculation tests were performed with raw effluent, in a batch reactor containing aluminum electrodes and glass vat. Sensors and a microcontroller make up the electronic system, which monitors and controls voltage, temperature, and time variables and also processes and sends the data to the computer. The tests consist of applying 1 and 2A current in a 3 liters volume taking aliquots in 5, 10, 15 min. The parameters analyzed were: pH, conductivity, turbidity, Chemical Oxygen Demand, and absorbance sweep in 200 to 800 nm range. The samples presented in the visible region a band with the maximum absorbance at 670nm; thus, it was decided to evaluate the system at this wavelength. The results of the electroflocculation tests showed that the best removal of turbidity, COD, and absorbance at 670nm occurred in the conditions of 2A / 10min, with average efficiency above 70%. A photovoltaic system was projected to meeting the demand for the energy electroflocculation system, whose analysis found that the best strategy is connecting the photovoltaic system to the electric power grid. Through financial simulation, It was identified as a significant energy-saving which offsets costs related to system installation. in conclusion, the system developed is efficient in textile effluent treatment and that the photovoltaic system meets the demand for energy from the electroflocculation system, ensuring project sustainability.


2020 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Pedro Henrique Mainardi ◽  
Ederio Dino Bidoia

Ecotoxicology is a science that studies the effects of pollutants and forecast their transformations on the environment. Ecotoxicological studies have been used in soil and water quality assessment, development and implementation of new techniques of water and effluent treatment, tools for better industrial management, bioremediation techniques and sustainable agriculture approaches. Microorganisms, which were seen to detain a fundamental importance in nutrient cycling and energy flow, have been increasingly used as bioindicators in ecotoxicological analyses. The populational inhibition of microbiological strains may be measured through the absorbance of visible light, an efficient, fast, low-cost and reliable method that has been widely used in qualitative and quantitative analysis. In this manuscript, a real textile effluent sample was analyzed regarding its electric conductivity, pH, turbidity, solids, alkalinity, biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and a spectrophotometry microbial population inhibition (MPI) method using the Bacillus subtilis bacteria and the Saccharomyces cerevisiae yeast. The EC20, EC50 and acute toxicity indexes were satisfactory in relation to the widely used method of light reduction of the Vibrio fischeri luminescence bacteria. The MPI was shown to be a feasible method to determine the hazardous effects caused by the textile effluent sample towards the microbial populations.


1973 ◽  
Vol 93 ◽  
pp. 74-103 ◽  
Author(s):  
John Gould

To Professor E. R. Dodds, through his edition of Euripides'Bacchaeand again inThe Greeks and the Irrational, we owe an awareness of new possibilities in our understanding of Greek literature and of the world that produced it. No small part of that awareness was due to Professor Dodds' masterly and tactful use of comparative ethnographic material to throw light on the relation between literature and social institutions in ancient Greece. It is in the hope that something of my own debt to him may be conveyed that this paper is offered here, equally in gratitude, admiration and affection.The working out of the anger of Achilles in theIliadbegins with a great scene of divine supplication in which Thetis prevails upon Zeus to change the course of things before Troy in order to restore honour to Achilles; it ends with another, human act in which Priam supplicates Achilles to abandon his vengeful treatment of the dead body of Hector and restore it for a ransom. The first half of theOdysseyhinges about another supplication scene of crucial significance, Odysseus' supplication of Arete and Alkinoos on Scherie. Aeschylus and Euripides both wrote plays called simplySuppliants, and two cases of a breach of the rights of suppliants, the cases of the coup of Kylon and that of Pausanias, the one dating from the mid-sixth century, the other from around 470 B.C. or soon after, played a dominant role in the diplomatic propaganda of the Spartans and Athenians on the eve of the Peloponnesian War.


DYNA ◽  
2017 ◽  
Vol 84 (203) ◽  
pp. 291-297 ◽  
Author(s):  
Juan Carlos Cueva-Orjuela ◽  
Angelina Del Socorro Hormaza-Anaguano ◽  
Andrés Merino-Restrepo

En Colombia, la caña de azúcar representa el segundo cultivo con mayor extensión. Se estima que a partir de los ingenios azucareros se producen aproximadamente 6 millones de toneladas de bagazo de caña de azúcar, BCA, de los cuales 5 millones son utilizados ineficientemente para la quema de calderas. El BCA está compuesto principalmente por celulosa, hemicelulosa y lignina, posibilitando su uso como un potencial adsorbente. En particular, en esta investigación se evaluó la viabilidad del BCA para la remoción del rojo básico 46, RB46, en solución acuosa. El efecto de factores tales como el punto de carga cero, pH de la solución, tamaño de partícula, dosificación del adsorbente, concentración inicial del colorante, tiempo de contacto y fuerza iónica fueron evaluados a través de un diseño estadístico. Se obtuvo una remoción del 86.4% y la posterior optimización del proceso, a través un diseño de superficie de respuesta, permitió alcanzar una adsorción máxima del 95.0%. Estos resultados sugieren que el BCA representa una alternativa promisoria de un adsorbente no convencional que puede ser aprovechado para el tratamiento de efluentes coloreados.


2021 ◽  
Vol 411 ◽  
pp. 67-78
Author(s):  
Ivy Ai Wei Tan ◽  
J.R. Selvanathan ◽  
M.O. Abdullah ◽  
N. Abdul Wahab ◽  
D. Kanakaraju

Palm oil mill effluent (POME) discharged without treatment into watercourses can pollute the water source. Microbial fuel cell (MFC) has gained high attention as a green technology of converting organic wastewater into bio-energy. As an approach to overcome the limitations of the existing POME treatment methods, air-cathode MFC-Adsorption system is introduced as an innovative technology to treat POME and generate bio-electricity simultaneously. However, the use of conventional MFC with proton exchange membrane in large scale applications is restricted by the high cost and low power generation. Addition of mediator in MFC is essential in order to increase the electron transfer efficiency, hence enhancing the system performance. This study therefore aims to investigate the effect of different type of mediators i.e. congo red (CR), crystal violet (CV) and methylene blue (MB) on the performance of an affordable air-cathode MFC-Adsorption system made from earthen pot with POME as the substrate. The addition of different mediators altered the pH of the MFC-Adsorption system, in which more alkaline system showed better performance. The voltage generated in the system with CR, CV and MB mediator was 120.58 mV, 168.63 mV and 189.25 mV whereas the current generated was 2.41 mA, 3.37 mA and 3.79 mA, respectively. The power density of 290.79 mW/m3, 568.72 mW/m3 and 716.31 mW/m3 was produced in the MFC-Adsorption system with CR, CV and MB mediator, respectively. The highest POME treatment efficiency was achieved in MFC-Adsorption system with MB mediator, which resulted in biochemical oxygen demand, chemical oxygen demand, total suspended solids, turbidity and ammoniacal nitrogen removal of 75.3%, 84.8%, 91.5%, 86.1% and 23.31%, respectively. Overall, the air-cathode MFC-Adsorption system with addition of MB mediator was feasible for POME treatment and simultaneous bio-energy generation.


2015 ◽  
Vol 28 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Thomas Bersinger ◽  
Isabelle Le Hécho ◽  
Gilles Bareille ◽  
Thierry Pigot ◽  
Alexandre Lecomte

Continuous monitoring of the sanitation network of the urban catchment of Pau (southwest France) has been performed since March 2012 using rain gauges, flowmeters, as well as turbidity and conductivity probes. Good correlations were obtained between turbidity, total suspended solids (TSS) and chemical oxygen demand (COD) on the one hand, and conductivity and total nitrogen on the other hand. This allowed an instantaneous and continuous estimation of pollutant concentrations and fluxes since that date. In the present paper we focused on the results of October 2012, which was characterized by alternating periods of dry and rainy events. Turbidity and conductivity raw data show different trends during the study period depending on the parameter and the rain events. A turbidity peak is observed at the beginning of each rain event but its amplitude varies with the intensity of the rain and the length of the preceding dry weather period. Conversely, conductivity decrease during each rain event implying, that rain water acts as a dilution factor. The behaviour of COD and total nitrogen differ markedly due to their partitioning between the dissolved (total nitrogen) and particulate phases (COD). Daily pollutant fluxes allow a global comprehension and monitoring of the sewer system. Important COD fluxes during a rain event preceded by a long dry weather period highlight the importance of erosion of sedimentary deposits in the sewerage network. During these events, important fluxes are discharged into receiving water leading to the question of the impact on aquatic life. Generally, these results highlight the potential of online monitoring to better understand the behaviour of the sewer network on long or short time scales. This could be a useful tool to manage wastewater treatment.


Author(s):  
Sari J Laihonen ◽  
Helena Greijer

Aim of this work was to study how degree of crystallinity influences the DC conduction characteristics of capacitor grade polypropylene (PP). PP pellets were pressed to 0.3 mm plates using two different cooling rates in order to vary the degree of crystallinity. The DC conduction currents were measured at 50 and 70 °C at 8-55 kV/mm. 3 h polarization and 15 h depolarization times were used. It turned out that temperature and the dielectric stress played a more dominant role regarding DC-conductivity than the obtained ~4 wt-% difference in crystallinity. Especially at 39-55 kV/mm, when temperature increased from 50 to 70 °C the DC-conductivity increased 10-15 times. There was however a trend related to the degree of crystallinity: the increase in crystallinity (more slowly sample cooling) led to lower conductivity values.


Author(s):  
Weerana Eh Kan ◽  
Jamil Roslan ◽  
Ruzinah Isha

<p>Conservative desalination technology including distillation requires high energy and cost to operate. Hence, pretreatment process can be done prior to desalination to overcome energy demand and cost reduction. Objective of this research is to study the effect of calcination temperature of hybrid catalyst in photocatalytic reactor system in the seawater desalination, i.e. salt removal in the seawater. The catalyst was synthesized via wet impregnation method with 1:1 weight ratio of TiO<sub>2</sub> and activated oil palm fiber ash (Ti:Ash). The catalyst was calcined at different temperature, i.e. 500 <sup>o</sup>C and 800 <sup>o</sup>C. The study was carried out in a one liter Borosilicate photoreactor equipped with mercury light of 365 nanometers for two hours with 400 rpm mixing and catalyst to seawater sample weight ratio of 1:400. The Chemical Oxygen Demand (COD), pH, dissolved oxygen (DO), turbidity and conductivity of the seawater were analyzed prior and after the testing. The fresh and spent catalysts were characterized via X-Ray Diffractogram (XRD and Nitrogen physisorption analysis. The calcination temperature significantly influenced the adsorption behaviour and photocatalytic activity. However, Ti:Ash which calcined at 800 <sup>o</sup>C has less photocatalytic activity. It might be because the surface of fiber ash was sintered after calcined at high temperature. The Ti:Ash catalyst that calcined at 500 <sup>o</sup>C was found to be the most effective catalyst in the desalination of seawater by reducing the salt concentration of more than 9 % compared to Ti:Ash calcined at 800 <sup>o</sup>C. It can be concluded that catalyst calcination at 500 °C has better character, performance and economically feasible catalyst for seawater desalination. Copyright © 2016 BCREC GROUP. All rights reserved</p><p><em>Received: 22<sup>nd</sup> January 2016; Revised: 23<sup>rd</sup> February 2016; Accepted: 23<sup>rd</sup> February 2016</em></p><strong>How to Cite:</strong> Kan, W.E., Roslan, J., Isha R. (2016). Effect of Calcination Temperature on Performance of Photocatalytic Reactor System for Seawater Pretreatment. <em>Bulletin of Chemical Reaction Engineering &amp; Catalysis</em>, 11 (2): 230-237 (doi:10.9767/bcrec.11.2.554.230-237)<p><strong>Permalink/DOI:</strong> http://dx.doi.org/10.9767/bcrec.11.2.554.230-237</p>


2019 ◽  
Vol 11 (3) ◽  
pp. 373-381
Author(s):  
M. Abdulla-Al-Mamun ◽  
B. R. Goush

The natural rise-husk charcoal was made by burned in a furnace at 230 °C. Carboxylic group (-COOH) was functionalized onto the charcoal by using oxalic acid in situ process. Fourier Transform Infrared Spectroscopy (FTIR) and morphology by Scanning Electron Microscope (SEM) demonstrated that the COOH-group was successfully functionalized on the charcoal and the particles were porous. The COOH-activated charcoal was applied for liming effluent treatment through a filtration media. Eight environmental load parameters was determined by the standard method. The results were compared with the standard permissible limits set by Inland Surface Water-Bangladesh Standards (ISW–BDS-ECR, 1997). It has been observed that the rice husk based activated carbons dramatically reduce the pollutants to permissible level. The removal efficiency of pH, Electrical Conductivity (EC), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), Biological Oxygen Demand in 5 days at 20 °C (BOD5), Chemical Oxygen demand (COD), Total Alkalinity, S2- from liming effluent up to 40.0%, 85.89%, 98.8%, 81.32%, 96.74%, 78.6%, 97.15% and 79.61% respectively. In conclusion, the liming effluent simply recycled by filtration process and can be used for industrial purpose.


Sign in / Sign up

Export Citation Format

Share Document