Degradasi Zat Warna Artifisial Limbah Tekstil dengan Advanced Oxidation Processes Menggunakan Katalis Nanopartikel Ce/Karbon

One of the innovation textile waste processing is advance oxidation processes using peroxymonosulfate and catalyst nanoparticle Ce/carbon. This study was aimed to decrease content of artificial dye waste and determined the optimum conditions by using catalyst nanoparticle Ce/carbon. Catalyst synthesis was processed in hydrothermal autoclave at temperature 1800C for 18 hours, it convert D-glucose into black carbon, then impregnated with catalyst metal Ce by 3% and 5% by weight, after that catalyst calcined by N2 at temperature 5000C for 4 hours. Adsorption of artificial dye textile waste was held 25 ppm for 2 hours with concentration of catalyst 0,4 gr/L. The optimum adsorption of artificial dye textile waste with catalyst concentration 0,4 gr/L was is 12,921 with adsorption percentage reached 48,32%

Pengolahan Zat Warna Tekstil (Rhodamine B) dengan Teknologi AOP (Advance Oxidation Processes) Menggunakan Katalis Ce@Carbon Sphere dan Oksidan Peroxymonosulfate

Waste water of textile industry contributes in environmental pollution, especially wastewater containing dye and organic compounds are dangerous because they are non-biodegradable, toxic and harmful to the environment, like as Rhodamine B. Therefore, it is necessary to do the processing of waste dye textile industry to reduce the impact of pollution on the environment. One of the lastest innovations in the processing of textile waste is using advanced oxidation processes (AOPs) by oxidant capable of generating a radical sulphate (SO4*). This study aims to determine the activity of Ce@Carbon Sphere as a catalyst in the oxidation process, to degradation of dye in wastewater by using a combination of peroxymonosulfate and catalyst Ce@Carbon Sphere as an oxidater, and determine the optimum conditions to reduce dye in water. Catalytic synthesis process carried out by the hydrothermal process to produce black carbon from D-glucose and Cerium Nitrate Hexahidrate solution, at 180oC for 18 hours in an autoclave. Then calcined with N2 at 550oC for 2 hours. Degradation of Rhodamine B (waste artificially) 25 ppm for 2 hours with various concentrations of the catalyst 0,1; 0,2; 0,3 and 0,4gr/L and the concentration proxymonosulfate 1; 2; 3 and 4 g/L. One oft the conditions for reducing the levels of Rhodamine B in water is concentration of peroxymonosulfate at 1 g/L and Ce@Carbon Sphere at 0,1 g/L with efficiency up to 32,59%

Pengolahan Limbah Tekstil Artifisial (Zat Warna Reaktif) dengan Proses Oksidasi Katalitik Menggunakan Nano-Mn/Carbon Sphere

The latest innovations in the processing of textile waste is using advanced oxidation processes (AOPs) by oxidant capable of generating a radical sulphate (SO4*). The purpose of this research is to determine catalyst activity of Nano-Mn/CS in oxidation process, reduce the dye on using peroxymonosulfate and Nano-Mn/CS, and determine the optimum conditions for reducing the dye in water. Catalytic synthesis process carried out by the hydrothermal process at temperature of 180o C for 18 hours in an autoclave to produce black carbon from D-glucose solution and then it will be impregnated with a variation of 3% and 5% Mn. Then it calcined with N2 at temperature of 500o C for 4 hours. The optimum condition for degradation of methylene blue (artificial wastes) 25 ppm carried out for 120 minutes with 0,2 gr/L catalysts Nano-Mn/CS and 4 gr/L oxone with efficiency of 91.07%

Degradation of azo dye orange G in aqueous solutions by persulfate with ferrous ion

2009-2010 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Optimization of Disperse Blue 3 mineralization by UV-LED/FeTiO3 activated persulfate using response surface methodology

Response surface methodology based on Box-Behnken design (BBD) was successfully applied for the optimization of the UV-LED/FeTiO3 activated persulfate (PS) process. Disperse Blue 3 (DB3) azo dye oxidation was carried out in a quartz jacketed stirred batch reactor using 405 nm UV at 10 W/m−2 as radiation source. The effects of temperature, catalyst concentration and persulfate dose upon the total organic carbon (TOC) removal were investigated. Optimum operating conditions were found to be: ilmenite: 320 mg/L−1, PS: 1.56 g/L−1 and 67°C. Under these conditions, 96% mineralization was achieved. Ecotoxicity of the final effluent was evaluated using Aliivibrio fischeri bacteria, finding a negligible toxicity.Comunidad Autónoma de Madrid and MINECO have supported this work through projects S2013/MAE-2716 and CTM2016-76454-R, respectively. Jefferson E. Silveira and Wendel S. Paz gratefully acknowledge the support from CAPES: Science Without Borders Program, Ministry of Education Brazil, under grants BEX-1046/13-6 and BEX-9476/13-0 respectively

Activation of sodium persulfate by magnetic carbon xerogels (CX/CoFe) for the oxidation of bisphenol A: Process variables effects, matrix effects and reaction pathways

An advanced oxidation process comprising sodium persulfate (SPS) and a novel magnetic carbon xerogel was tested for the degradation of bisphenol A (BPA), a model endocrine-disrupting compound. The catalyst, consisting of interconnected carbon microspheres with embedded iron and cobalt microparticles, was capable of activating persulfate to form sulfate and hydroxyl radicals at ambient conditions. The pseudo-first order degradation rate of BPA in ultrapure water (UPW) was found to increase with (i) increasing catalyst (25–75 mg/L) and SPS (31–250 mg/L) concentrations, (ii) decreasing BPA concentration (285–14,200 μg/L), and (iii) changing pH from alkaline to acidic values (9–3). Besides UPW, tests were conducted in drinking water, treated wastewater, groundwater and surface water; interestingly, the rate in UPW was always lower than in any other matrix containing several organic and inorganic constituents. The effect of natural organic matter (in the form of humic acids) and alcohols was detrimental to BPA degradation owing to the scavenging of radicals. Conversely, chlorides at concentrations greater than 50 mg/L had a positive effect due to the formation and subsequent participation of chlorine-containing radicals. Liquid chromatography time-of-flight mass spectrometry was employed to identify major transformation by-products (TBPs) of BPA degradation in the absence and presence of chlorides; in the latter case, several chlorinated TBPs were detected confirming the role of Cl-related radicals. Based on TBPs, main reaction pathways are proposed.Z. Frontistis would like to thank the Greek State Scholarships Foundation (IKY) for the financial support of this research through the “IKY Fellowships of Excellence for Postgraduate Studies in Greece e Siemens Programme” in the framework of the Hellenic Republic e Siemens Settlement Agreement. Part of this work was financially supported by: Project POCI-01- 0145-FEDER-006984 - Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 e Programa Operacional Competitividade e Internacionalizaç~ao (POCI) - and by national funds through FCT - Fundaçaeo para a Ciencia e a Tecnologia. R.S. Ribeiro acknowledges the FCT individual Ph.D. grant SFRH/BD/94177/2013, with financing from FCT and the European Social Fund (through POPH and QREN). A.M.T. Silva acknowledges the FCT Investigator 2013 Programme (IF/01501/2013), with financing from the European Social Fund and the Human Potential Operational Programme.Z. Frontistis would like to thank the Greek State Scholarships Foundation (IKY) for the financial support of this research through the “IKY Fellowships of Excellence for Postgraduate Studies in Greece e Siemens Programme” in the framework of the Hellenic Republic e Siemens Settlement Agreement. Part of this work was financially supported by: Project POCI-01- 0145-FEDER-006984 - Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 e Programa Operacional Competitividade e Internacionalizaç~ao (POCI) - and by national funds through FCT - Fundaçaeo para a Ciencia e a Tecnologia. R.S. Ribeiro acknowledges the FCT individual Ph.D. grant SFRH/BD/94177/2013, with financing from FCT and the European Social Fund (through POPH and QREN). A.M.T. Silva acknowledges the FCT Investigator 2013 Programme (IF/01501/2013), with financing from the European Social Fund and the Human Potential Operational Programme.info:eu-repo/semantics/publishedVersio

Substrate Oxidation Enhances the Electrochemical Production of Hydrogen Peroxide

Hydrogen peroxide (H_2O_2) is electrochemically produced via oxygen (O_2) reduction on a carbon cathode surface. In order to enhance the production of H_2O_2, anodic loss pathways, which significantly reduce the overall H_2O_2 production rate, should be inhibited. In this study, we investigate the effects of organic electron donors (i.e., typical chemical contaminants) on the anodic loss pathways of H_2O_2 in a single-cell electrochemical reactor that employs an anode composed of TiO_2 over-coated on a mixed-metal oxide ohmic contact catalyst, Ir_(0.7)Ta_(0.3)O_2, deposited on a Ti-metal that is coupled with a graphite rod cathode in a sodium sulfate (Na_2SO_4) electrolyte that is saturated with oxygen (O_2). Organic electron donors are shown to enhance the electrochemical production of H_2O_2, while simultaneously undergoing oxidative degradation. The observed positive effect of organic electron donors on the electrochemical production of H_2O_2 is due in part to a preferential adsorption of organic substrates on the TiO_2 outer layer of the anode. The sorption of the organic electron donors inhibits the formation of surficial titanium hydroperoxo species ( Ti-OOH) on the anode surface. The organic sorbates also act as scavengers of surface-bound hydroxyl radical Ti-OH. As a result, the decomposition of H_2O_2 on the anode surface is significantly reduced. The cathodic production rate of H_2O_2 at low pH is enhanced due to proton coupled electron transfer (PCET) to O_2, while the anodic decomposition of H_2O_2 is inhibited due to electrostatic interactions between negatively-charged organic substrates and a positively-charged outer surface of the anode (TiO_2 pH_(zpc) = 5.8) at low pH

Hydrothermal synthesis of reduced graphene oxide-CoFe2O4 heteroarchitecture for high visible light photocatalytic activity: Exploration of efficiency, stability and mechanistic pathways

RGO-CoFe2O4 heterostructure nanocomposite was prepared by hydrothermal method and was characterized by various analytical techniques such as Powder X-ray Diffraction method (PXRD), UV-vis absorbance, Photoluminescence (PL), Fourier Transform Infra Red (FTIR) spectroscopic techniques, BET surface area measurements, Field Emission Scanning Electron Microscopy (FESEM), Raman Spectroscopy and Vibrating Sample Magnetometer (VSM). The results confirmed the formation of hybrid structure with CoFe2O4 particles embedded in RGO sheets. Photocatalytic activity of the nanocomposites was probed for the degradation of 4-Chlorophenol (4-CP) as the model compound under the visible light illumination. The photocatalytic activity decreases in the following order RGO-CoFe2O4 > CoFe2O4 > RGO. Further the activity of RGO-CoFe2O4 composite was explored in the presence of peroxymonosulfate (PMS) as an oxidant. LUMO of PMS can accommodate photogenerated electrons, thereby suppresses the recombination process. The enhanced activity of RGO-CoFe2O4 hybrid is compared to its individual counterparts and the higher activity is accounted to its unique electronic structure. RGO serves as electron acceptor from CoFe2O4 and electron donor to the oxygen molecule. During the photocatalysis, transformation of the native structure from normal spinel to inverse spinel and vice versa may take place continuously from the process of electron trapping and detrapping by Fe3+ and Co2+ions. The observed continuous absorption for RGO-CoFe2O4 composite in the UV-vis spectra implies active d-d transitions involving transition metals present in the nanocomposite. © 2017 Elsevier Ltd. All rights reserved

7‑hydroxymitragynine is an active metabolite of mitragynine and a key mediator of its analgesic effects

Mitragynina speciosa, more commonly known as kratom, is a plant native to Southeast Asia, the leaves of which have been used traditionally as a stimulant, analgesic, and treatment for opioid addiction. Recently, growing use of the plant in the United States and concerns that kratom represents an uncontrolled drug with potential abuse liability, have highlighted the need for more careful study of its pharmacological activity. The major active alkaloid found in kratom, mitragynine, has been reported to have opioid agonist and analgesic activity in vitro and in animal models, consistent with the purported effects of kratom leaf in humans. However, preliminary research has provided some evidence that mitragynine and related compounds may act as atypical opioid agonists, inducing therapeutic effects such as analgesia, while limiting the negative side effects typical of classical opioids. Here we report evidence that an active metabolite plays an important role in mediating the analgesic effects of mitragynine. We find that mitragynine is converted in vitro in both mouse and human liver preparations to the much more potent mu-opioid receptor agonist 7-hydroxymitragynine, and that this conversion is mediated by cytochrome P450 3A isoforms. Further, we show that 7-hydroxymitragynine is formed from mitragynine in mice and that brain concentrations of this metabolite are sufficient to explain most or all of the opioid-receptor-mediated analgesic activity of mitragynine. At the same time, mitragynine is found in the brains of mice at very high concentrations relative to its opioid receptor binding affinity, suggesting that it does not directly activate opioid receptors. The results presented here provide a metabolism-dependent mechanism for the analgesic effects of mitragynine and clarify the importance of route of administration for determining the activity of this compound. Further, they raise important questions about the interpretation of existing data on mitragynine and highlight critical areas for further research in animals and humans.</p

Augmenting intrinsic fenton-like activities of MOF-derived catalysts via N-molecule-assisted self-catalyzed carbonization

To overcome the ever-growing organic pollutions in the water system, abundant efforts have been dedicated to fabricating efficient Fenton-like carbon catalysts. However, the rational design of carbon catalysts with high intrinsic activity remains a long-term goal. Herein, we report a new N-molecule-assisted self-catalytic carbonization process in augmenting the intrinsic Fenton-like activity of metal–organic-framework-derived carbon hybrids. During carbonization, the N-molecules provide alkane/ammonia gases and the formed iron nanocrystals act as the in situ catalysts, which result in the elaborated formation of carbon nanotubes (in situ chemical vapor deposition from alkane/iron catalysts) and micro-/meso-porous structures (ammonia gas etching). The obtained catalysts exhibited with abundant Fe/Fe–Nx/pyridinic-N active species, micro-/meso-porous structures, and conductive carbon nanotubes. Consequently, the catalysts exhibit high efficiency toward the degradation of different organic pollutions, such as bisphenol A, methylene blue, and tetracycline. This study not only creates a new pathway for achieving highly active Fenton-like carbon catalysts but also takes a step toward the customized production of advanced carbon hybrids for diverse energy and environmental applications