mL Of H2O2 Research Articles

Instrumental characterization of merino wool fibers dyed with Cinnamomum camphora waste/fallen leaves extract: An efficient waste management alternative

The present study describes the use of Cinnamomum camphora waste/fallen leaves as an eco-friendly natural colorant for developing colorful and antibacterial wool fibers in view of growing environmental pollution and increasing needs for biomedical textiles in healthcare sector. Extraction of the natural colorant from C. camphora reddish colored/middle-aged waste/fallen leaves was carried out via simple water bath and ultrasound water bath extraction methods. While optimizing the colorant extraction in an aqueous solvent, ultrasound water bath provided enhanced extraction efficiency at pH 3, temperature of 70 °C, an initial dose level of 1.0 gm/50 ml of H2O, time of 80 min, and ultrasonic frequency of 80 kHz. Phytochemical analysis of extracted dye was successfully carried out using simple qualitative experimental analysis. The extracted colorants from C. camphora waste leaves were used to dye merino wool fibers through exhaustion dyeing technique. The optimal dyeing conditions, dye performances, and the ultrasonic effects were reported effectively. Build-up properties and fastness characteristics were studied in the presence and absence of mordants under corresponding ISO standards. Increasing ethanol concentration, increased discoloration properties of dyed wool fiber. Dyeing kinetics and dyeing rates under both simple water bath and ultrasound water bath conditions were compared. The structural and thermal changes in the dyed fibers under both conditions were analyzed using FT-IR, TG, and SEM analysis. An adequate amount of C. camphora leaves extract on wool fiber exhibited good antibacterial behaviors with high durability to increasing number of washing cycles. Premordanting with Cu2+, Fe2+, and Al3+ salts had a slightly negative effect on the antibacterial activity of dyed wool fibers but showed enhanced durability. Camphor waste leaves will prove great potential for industrial application as a source of natural colorant, as well as a value-adding application (biomedical textile) in addition to its normal usage.

Ultrasonic renovation mechanism of spent LCO batteries: A mild condition for cathode materials recycling

Recycling of spent lithium-ion batteries was an important step for the utilization of waste electric and electronic equipment. Commonly studies mainly focused on metal extraction while bringing the waste of chemical reagents, secondary pollution, and energy consumption. The reasons for the failure of lithium-ion batteries were the pore blocking by organics and the structural collapse in LiCoO2 crystal. Ultrasonic hydrothermal renovation was a promising method to directly renovate spent LiCoO2 crystal structure and remove the organics. It combined the advantages of ultrasonic and hydrothermal technologies which were high-efficiency and clean production. Ultrasonic cavitation generated by high-powered ultrasonic in liquid phase was a process with bubble formation and implosion. Under the effect of ultrasonic cavitation and advanced oxidation synergistically, the blocked channels and layer structure were effectively rebuilt, the organics were removed and the crystal structure of LiCoO2 was renovated. This experimental result showed that the optimal renovation condition was at the ultrasonic power of 1050 W, the reaction temperature of 90 ℃, the reaction time of 6 h, 1 mL of H2O2, and 0.5 MPa of Ar gas content. The renovated LiCoO2 exhibited good electrochemical properties, the first charge and discharge capacity of 132.1mAh•g − 1 and 131.0mAh•g − 1, and the first cycle efficiency arrived at 99.16%. Additionally, an environmentally friendly and efficient route for the recycling of spent lithium-ion batteries was developed.

Manganese ferrite dispersed over graphene sand composite for methylene blue photocatalytic degradation

Abstract Magnetic materials can be considered as promising catalysts for the degradation of various organic pollutants in wastewater treatment as they can be easily separated with visible light response. The purpose of this research was to develop a highly efficient photocatalyst in decomposing methylene blue (MB) was synthesized using MnFe2O4 nanoparticles supported on graphene sand composite (MnFe2O4-GSC), resulting in an easily, magnetically separable and recyclable photocatalyst. MnFe2O4-GSC was prepared by a solvothermal methodology using commercial sand, graphene oxide (GO) and metal ions (Fe3+ and Mn2+) as precursor materials. The photocatalyst was characterized by scanning electron microscopy, X-ray diffraction, differential reflectance spectroscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy and zeta potential analysis. The results indicated that MnFe2O4 had a spherical shape with uniform size of about 200 nm were successfully loaded and dispersed on the graphene nanosheets and on the sand’s surface. The photocatalytic performance of MnFe2O4-GSC for MB degradation under visible light irradiation was investigated with different reaction conditions, H2O2 concentration, catalyst dosage and pH. The use of the MnFe2O4-GSC as a heterogeneous photocatalyst achieved 100 % degradation of 10 mg L−1 of MB solution at natural pH (pH 7.65) in the presence of 5 mL of H2O2 and 180 min of contact time. In cyclic photodegradation experiments, the performance of MnFe2O4-GSC was stable and practically unchanged regarding its efficiency after five runs. Thus, this research provided a promising strategy for designing efficient and magnetically recyclable photocatalysts for decontamination of dye wastewater under visible light irradiation.

Injection mixed drug intratumoral to produce ROS and creating a coagulum as cancer therapeutics drug depot.

e15635 Background: To explore the nature of hydrogen peroxide at higher dosage for denature-aggregation of tumor with drugs through aggregation in denatured tumor as a coagulum for drug depot and prolong function of drug. Methods: (1). Preparation for two 5 ml of BLM-I131, one diluted with 0.12 ml NS and 0.2 ml (0.2mCi = 49.67µg BLM) for tumor injection in control group; one diluted with 0.12 ml of H2O2 (0.833 mg/ml) and 0.2 ml (0.2mCi = 49.67µg BLM) for tumor injection in experimental group. (2).Tumor imaging with BLM-I131 analyzed at different time points. (3). Radioactivity in tumor of mice analyzed under SPECT scanning imaging instrument at the 0, 5 h, 1 h, 2 h, 4 h, 8 h, 24 h, 48 h, 96 h, 120 h, 144 h and 168 h, activity of isotope I131 is representing the BLM retaining time in tumor. (4). Also, tumor sectioned and observed cellular and extracellular matrix changes of histological structure. Results: It was observed that BLM-I131 with ROS in tumors sustained for 168 hours while BLM-I131 with NS in tumors sustained for 8 hours only. Radioactivity of BLM-I131 in tumors with ROS reach at peak 1.5 hours and second peak at 20 hours by average to extend to 168 hours, while radioactivity of BLM-I131 in tumors with NS reached at peak in 0.5 hour, decreased to 30% in 1.5 hour quickly to background in 8 hours; We observed the extracellular matrix changes in experimental tumor while no changes in control tumor. Conclusions: A water soluble oxidant mixed with free drug can play a biological scissors role to chop tumor matrix, then it resulted in a denature tumor matrix into a coagulation for a drug depot, it showed drug of BLM-I131 sustained in tumor for a long time; while oxidant plays an important role to punch holes on cell membrane and resulted a high permeability for high concentration drug in each cancer cells.

Coating phosphorus fertilizer with renewable natural polymers

Low phosphorus use efficiency (PUE) is one of the major reasons of poor production worldwide. Among the various approaches used to enhance PUE, polymer coated fertilizers are relatively a new concept. Its main advantages are that they dissolve slowly and release nutrients to plants gradually during the growing season. Keeping this in view, a study was performed in the laboratory to evaluate polymers coated monoammonium phosphate (MAP) to enhance PUE. Commercial MAP and MAP coated with biodegradable polymers with Krafit black liquor (BL) and cellulose acetate (CA) in the concentration (0.5, 1.0, 2.0 wt % coating). The effectiveness of these coatings was assessed by the electrical conductivity (EC) and phosphorus release (PR) in a kinetic experiment. The kinetic study was carried out in a controlled environment (± 25 °C), following the release pattern of P from 1.5 g of fertilizer in 50 mL of H2O, with and without the coatings. The objective of this work was to study different lignin-based coatings and the phosphorus release behavior of the resulting fertilizer. EC showed to be an effective method of indirect analysis of P releasing from coated MAP. The BL coating presented better results than the CA in terms of controlling the release of P, and the higher the coating ratio (1.0 and 2.0 %) the slower the release of P.

Microwave-assisted digestion employing diluted nitric acid for mineral determination in rice by ICP OES

A microwave-assisted digestion method using diluted HNO3 was developed for further determination of Al, Ca, Cr, Cu, Fe, K, Mn, Mo and Ni in rice samples by ICP OES. The following optimized conditions were established after full factorial design: digestion time of 14 min, concentration of 1 mol L−1 HNO3 and 2.5 mL of H2O2. The efficiency in decomposing organic matter with diluted acid was higher than 89%. The methodology was validated using the SRM NIST 1568a Rice Flour and recovery tests, with agreement between the determined and certified/added concentration values, and RSD of up to 12%. The limits of detection of the method were in the range of 0.0087 mg kg−1 (Mn) to 1.6 mg kg−1 (Ca). In addition, a simple and inexpensive spectrophotometric method was proposed for the quantification of organic carbon in varied samples (carbohydrates, proteins, lipids) in the form of digested or solids.

MAGNETICALLY RECOVERABLE POLYMER CATALYST FOR CELLULOSE HYDROGENOLYSIS

A new type of Ru-containing magnetically recoverable catalyst based on a polymer matrix of hypercrosslinked polystyrene (HPS) for the reaction of the hydrogenolysis of microcrystalline cellulose to ethylene and propylene glycol (EG and PG) is proposed. The catalyst is synthesized sequentially in two stages. At the first stage, by means of thermal decomposition of iron (III) salts in the presence of polyols, magnetite particles (Fe3O4) are formed in the pores of the HPS. At the second stage, Ru-containing nanoparticles of the active phase of the catalyst are synthesized on the surface of Fe3O4/HPS. Samples of the original HPS, Fe3O4/HPS and Ru-Fe3O4/HPS were characterized using various physicochemical methods. In particular, it was shown that the synthesized samples of catalysts have a high specific surface area (450 - 750 m2/g, depending on the magnetite content), retain the micro-mesoporous nature of the original polymer, and have a high saturation magnetization (4.0 ± 0.5 emu /g), which makes them easy to separate from the reaction mass by an external magnetic field. According to the results of transmission electron microscopy (TEM), the average diameter of the nanoparticles of the active phase Ru was 2.0 ± 0.5 nm. The hydrogenolysis of cellulose to glycols was carried out under the following conditions: 255 °C; 60 bar H2; 55 min; 0.3 g of cellulose; 0.07 g of catalyst 3% Ru-Fe3O4/HPS; 30 ml of H2O; 0.07 g of Ca(OH)2. Under these conditions, the selectivities for EG and PG were 22.6 % and 20.0 %, respectively. The degree of cellulose conversion reaches 100 %. The catalyst showed good stability under hydrothermal reaction conditions, is easily separated from the reaction mass by an external magnetic field, and can be used in the processes of cellulose-containing biomass conversion.

Determination of Trace and Major Elements in Vegan Milk and Oils by ICP-OES After Microwave Digestion.

Increasing technological developments also bring about environmental pollution. Heavy metals and metallic compounds, as a result of soil, water, and air industrialization, pass through to people and animals through the food chain and have a negative impact on health. In this study, the concentrations of Na, Mg, K, Ca, P, Fe, Cu, B, Mn, Zn, Al, S, As, Bi, Cd, Co, Cr, Mo, Ni, Pb, Pt, Sb, Se, Sn, Ti, W, and Hg in commercial vegan milk (soybean milk, coconut milk, and almond milk) and oils (soybean oil, coconut oil, bitter almond oil, sweet almond oil, and walnut oil) were determinated using inductively coupled plasma-optical emission spectrometry after microwave digestion. In order to compare the efficiencies of digestion in vegan milk and oil samples, 6mL of HNO3 (conc.), 3mL of H2O2 (30%); 7mL of HNO3 (conc.), 3.5mL of H2O2 (30%), and 8mL of HNO3 (conc.), 4mL of H2O2 (30%) were used in microwave digestion procedures. The proposed procedures were applied to the analysis of 81 vegan milk and 125 vegan oil samples covering three different brands in Turkey. Na, Mg, K, Ca, P, S, Mn, Zn, Cu, B, Sb, and Sn concentrations in vegan milks ranged (minimum-maximum in ppm) as follows: 307.4-501.2, 1.8-15.6, 478.8-1300.4, 276.3-1189, 197-797.8, 18.7-241.4, 0.09-0.42, 0-0.58, 0.02-1.06, 0.34-1.56, 0.26-0.67, and 3.4-30.4ppm, respectively. The results of Na, K, Ca, P, Mg, S, Mn, Zn, Se, Fe, Cu, Sb, and Sn concentrations in vegan oils (minimum-maximum in ppm) ranged as follows: 6.8-31.2, 403.5-425.2, 142.8-160.4, 71.65-149.8, 0.35-0.85, 14.2-35.2, 0.02-0.27, 0.07-0.36, 1.90-4.64, 0.92-5.36, 0.01-0.05, 1.02-1.66, and 21.2, 35.0ppm, respectively. Vegan milk contents except for Se, Fe, Sb, and Sn in this study were higher than vegan oil contents. The methods were validated by linearity, limits of detection and quantification, precision, and analyzing certified reference material (NIST SRM-3235), soybean milk. The highest values of LOD were found Pb, P, and Bi, and the highest values of LOQ were found Mo, Pb, and Sb.

PHOTOCATALYTIC DEGRADATION OF DISPERSE BLUE 56 BY Cu-Ti-PILCs AND Fe-Ti-PILCs

Pollution with aromatic hydrocarbon has been rising because of the extreme usage of benzene containing compounds. Most of the people, animals and plants have been exposed to aromatic hydrocarbons due to polluted water sources. The aim of the present work was to carry out an experimental study for the photocatalytic degradation of aromatic hydrocarbon containing compounds by iron-titanium-pillared interlayered clays (Fe-Ti-PILCs) and copper-titanium-pillared interlayered clays (Cu-Ti-PILCs). For this purpose, a dye named disperse blue 56 (DB56) was selected for treatment experiment. Zeolite was used as a catalyst support material to prepare Fe-Ti-PILCs and Cu-Ti-PILCs. The experiments were carried out in batch method and UV-Vis spectroscopy was used for analysis. Several parameters such as contact time, H2O2 and amount of PILCs were examined to find optimized conditions. The obtained degradation rates using Cu-Ti-PILCs were better than Fe-Ti-PILCs. The obtained highest removal rates were ~97% and ~94% for Cu-Ti-PILCs and Fe-Ti-PILCs, respectively in 120 min reaction time with using 100 mg/L of dye, 1 g of Fe-Ti-PILC and Cu-Ti-PILCs and 1 mL of H2O2.

Artificial neural network employment for element determination in Mugil cephalus by ICP OES in Pontal Bay, Brazil.

Fish are important sources of protein, making them very significant in the human diet. Although the consumption of this food is beneficial for health, it is essential that the product does not contain inorganic components above the limits recommended by the current legislation. Therefore, a method for determination of elements in fish (Mugil cephalus) samples was optimized. A simplex centroid mixture design with restriction was applied for optimization of the acid digestion of samples in an open system under reflux in order to evaluate the best ratio between the reagents HNO3, H2O2 and H2O. The results indicated that more intense analyte signals were obtained when a mixture containing 3.6 mL of HNO3 (65% v/v), 0.4 mL of H2O2 (30% v/v) and 6.0 mL of H2O was used. The accuracy of the method was assessed with a CRM of oyster tissue (NIST 1566b). The method presented relative standard deviations (RSDs) of 3.54%; 3.82%; 4.81% and 3.50% for Zn, Fe, Cu and S, respectively. The detection limits were 0.002 mg kg-1 for Cu and Zn and 0.02 mg kg-1 for Fe and S. The proposed method was applied for the determination of Zn, Fe, Cu and S in fish samples. A Kohonen Self-Organizing Map (KSOM) with K-means implementation was applied to better delimit the boundary between groups and the spatial and temporal influence on how concentrations of the chemical elements were perceived. To verify the separation, the Davies-Bouldin and Silhouette indices were used, obtaining 0.5374 and 0.8541, respectively, indicating satisfactory separation.

A sustainable system for maleic acid synthesis from biomass‐derived sugar

AbstractBACKGROUNDThe preparation of maleic acid from the oxidation of renewable furfural has attracted significant attention, but research regarding the direct transformation of biomass‐derived sugar to maleic acid is rare. The research regarding the direct transformation of xylose to maleic acid would further promote its industrial applications.RESULTSThe direct synthesis of maleic acid from xylose was investigated based on a sustainable system of deep eutectic solvents (DESs). Four DESs were screened to evaluate their abilities for the dehydration of xylose. Hydrogen peroxide (H2O2) was then loaded to realize the oxidation of furfural without the separation of intermediates. A good maleic acid yield of 20.8%, along with 5.0% of fumaric acid, based on the xylose content were obtained under the initial xylose loading of 50 mM, a tin(IV) chloride (SnCl4)–xylose molar ratio of 4:1, in a monophase choline chloride (ChCl)–formic acid (Fa) (molar ratio of 1:6) system at 120 °C for 2 h. Then, 4 mL of H2O2 per mmol furfural was loaded for a further 10 min at 120 °C.CONCLUSIONThis ChCl–Fa–SnCl4–H2O2 system possesses a higher oxidation selectivity to maleic acid with no furanone and succinic acid. Moreover, it was interesting that ChCl and SnCl4 could be recovered through natural recrystallization. © 2019 Society of Chemical Industry

Fabrication of ZnO/FeVO4 heterojunction nanocomposite with high catalytic activity in photo-Fenton-like process

In this study, a novel heterojunction ZnO/FeVO4 nanocatalyst was synthesized through a simple method and used in a photo-Fenton-like oxidation reaction for the removal of an anionic surfactant. The synergistic effect of UV-light induced photocatalysis and Fenton-like process on the removal of sodium dodecyl sulfate (SDS) was analyzed using response surface methodology (RSM). Maximum SDS removal efficiency (99.0%) was achieved using 40 mg of the nanocomposite, 1.57 mL of H2O2 at pH 5.5 and 45 min. Compared to the pure FeVO4 and ZnO nanocatalysts, the synthesized nanocomposite exhibited higher catalytic activity in the degradation of SDS. Kinetic studies showed that the process could be described with pseudo-first-order, modified Freundlich and parabolic-diffusion models. The catalyst was also successfully applied for the treatment of real wastewaters containing surfactants. The facile synthesis, high catalytic activity and excellent reusability makes the ZnO/FeVO4 nanocatalyst promising for future applications in environmental remediation.

Determination and In Vitro Bioaccessibility Evaluation of Cu, Fe, Mn, and Zn in Chia (Salvia hispanica L.) Seeds by ICP OES

The objective of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, Mn, and Zn in chia seeds (Salvia hispanica L.) by inductively coupled plasma optical emission spectrometry (ICP OES). For the evaluation of the total content, a method of acid digestion was developed, using a complete factorial design 23, in a digester block with reflux system using cold finger, and the variables chosen were as follows: volume of nitric acid, sulfuric acid, and hydrogen peroxide. Optimization provided the best conditions considering 5.0 mL of HNO3 65% m m−1, 0.5 mL of H2SO4 98% m m−1, and 3.0 mL of H2O2 30% m m−1. The detection limits, in μg g−1, were 0.18 (Cu), 0.22 (Fe), 0.28 (Mn), and 0.37 (Zn). The analyte addition and recovery test were applied to evaluate the accuracy and recovery percentage values ranging from 84 to 114% were obtained, which is considered adequate for quantitative analysis. Precision was expressed as relative standard deviation (% RSD). It was less than or equal to 7.6% (n = 10) for all analytes. The procedure was applied to 10 samples of chia seed commercialized in Salvador (Brazil). The following concentration ranges, in μg g−1, were found: Cu (12–24.2), Fe (53.2–108), Mn (29.8–84.2), and Zn (45.8–77.4). Bioaccessibility was assessed using an in vitro method that takes into account the entire gastrointestinal tract. The following bioaccessible fractions were obtained in percent: Cu (3.6–14), Fe (5.2–5.5), Mn (5.8–29.1), and Zn (< 0.7 μg g−1). The procedure was validated through a mass balance (bioaccessible content + residual fraction compared with the total content), which presented percentages of recovery ranging from 82 to 156%. This new information provides a starting point for more complex evaluations from the nutritional point of view, including the establishment of a recommended daily dietary intake for this frequently consumed seed.

Highly efficient removal of surfactant from industrial effluents using flaxseed mucilage in coagulation/photo-Fenton oxidation process

In this study, flaxseed mucilage (FSM) has been used as a green coagulant in the pretreatment stage of a combined process for the removal of an anionic surfactant, sodium dodecyl sulfate (SDS). In the post-treatment stage, heterogeneous photo-Fenton-like oxidation using MnFe2O4 nanocatalyst was applied to remove the remained SDS. Using response surface methodological approach, optimum condition in the coagulation process was obtained at pH 7.0, FSM dose of 100 mg L−1 and 30 min. In the photo-Fenton oxidation process, complete SDS removal was achieved using 76 mg of the nanocatalyst, 1.07 mL of H2O2 at 17 min. Application of the combined process on the real wastewater samples indicates that the proposed method can be used effectively for the treatment of industrial effluents containing surfactants.

Performance Evaluation of Modified Black Clay as a Heterogeneous Fenton Catalyst on Decolorization of Azure B Dye: Kinetic Study and Cost Evaluation

Black clay (BC) was used as a catalyst for the decolorization of Azure B dye by Fenton process. BC was modified by acid, alkali, distilled water, and calcination to check their changes in characterization and efficiency on decolorization of Azure B. Among three modified catalysts, maximum decolorization was obtained by acid-modified BC (AMBC) catalyst due to the highest removal of impurities, comparatively. The characterization of AMBC was done by Fourier-transform infrared spectroscopy and X-ray diffraction spectroscopy which show the presence of metal ion. The BET surface area, pore volume, pore size, and density of AMBC were calculated to be 79.402 m2/g, 0.0608 m3/g, 0.00306 nm, and 16 g/cm3, respectively. The highest decolorization of 97.59% was achieved only in 10 min using AMBC at optimized calcination of 100 °C and 3 h of aging. AMBC was considered as the main catalyst for optimizing the different process parameters. Optimized conditions were obtained: pH 2, 0.2 mL of H2O2, catalyst dose 0.3 g, room temperature (30 °C), and stirring speed 400 r/min. The catalyst has showed excellent stability and reusability. It could remove more than 85% of color even after four cycles of run and less than negligible leaching of iron. AMBC has good recycling ability among other modified catalysts. To check the selectivity of catalyst, different dyes such as Congo red and mixed dye (mixture of Azure B and Congo red) decolorization were studied. In the present work, kinetic study was also carried out and a three-stage decolorization process was found.

Development of a point-of-contact technique to measure adenosine triphosphate: A quality improvement study.

PurposePatients with heart failure with preserved ejection fraction (HFpEF) experience fatigue due to impaired myocardial bioenergetics. Cardiomyocyte function depends on the delivery of adenosine triphosphate (ATP), yet there is no convenient bedside method to measure ATP. The purpose of this study was to develop a point-of-contact measurement of ATP that can be used in a clinical setting.MethodsIn a laboratory setting, digital finger punctures were conducted using 5 μl and 10 μl of capillary blood placed into various amounts of water (H2O). After mixing the solution for 10 s, a Hygiena AquaSnapTM Free ATP probe was placed into the solution for 10 s for the detection of ATP. The probe was then placed into the Hygiena luminometer for 15 s, and a value in relative light units (RLU) was obtained.ResultsTest samples using 10 μl of blood diluted from 50 to 500 mls of H2O produced ATP readings of 10,000-7569 RLUs. Using 5 μl of blood in 375–900 ml of H2O decreased the ATP values to 6459-4189 RLUs. Dilutional volume sparing experiments were conducted with ATP standards to determine the concentration of ATP per RLUs.ConclusionPatients with HFpEF have increased metabolic demand and impaired myocardial bioenergetics. Thus, identifying a method to measure ATP that is quick and accurate is imperative to accurately assess cellular energy production in this population. Point-of-contact measures, such as ATP, are needed for precision-guided treatment. Data from this study provides the first step toward developing evidence for health policies related to managing fatigue.

Hickman Run, Fairmont, WV stream quality assessment

Hickman Run stream needs rehabilitation because of pollution coming from various sources. Stream health was assessed through sampling of 10 different sites along Hickman Run stream, which drains into the Monongahela river. Chemical data was collected such as temperature, pH, conductivity, dissolved oxygen in addition to biological testing for coliform bacteria and the collection of aquatic macroinvertebrates. Conductivity measurements did not exceed 400 mg/L on days there were no precipitation. pH was between 6-9 at all sites except for sites 1-4 on one test day where there was active precipitation. Dissolved oxygen measured above 3 ppm at all sites. Fecal coliform count was at or below 200 fecal coliforms per 100 mL of H2O at all sites except for the furthest site downstream. On a test day in January 2019, all sites but 1 and 4 were above the fecal coliform threshold. On a test day in February 2019, all sites were below the fecal coliform threshold. 15 aquatic macroinvertebrates were collected, identified and assessed for pollutant tolerance using the Hilsenhoff Family Biotic Index. Overall, Hickman Run stream is in good condition at this time and does not need rehabilitation. This research was funded by a FSU NASA WV Space Grant Consortium Undergraduate Affiliate Fellowship grant.

Visible Light Induced Photocatalytic Degradation of Malachite Green by Solid State Synthesized MgFeO3–MgFe2MxO4 + δ (M = None, Mn4+, Ni2+, Zn2+, Eu3+, Dy3+, Yb3+) Nanocomposites

MgFe2O4 composite samples were synthesized by one-step solid state reactions between MgCl2 and FeCl3 at 600, 800 and 900 °C. The doped materials were synthesized using Ni(NO3)2, MnO2, Yb2O3, Zn(NO3)2 and Eu2O3dopant raw materials at 800 °C for 12 h. The obtained materials were characterized by powder X-ray diffraction technique. Rietveld analysis data showed that the obtained MgFe2O4 materials were crystallized in the cubic crystal system with the space group Fd-3m and lattice parameters a = b = c = 8.38 A. The morphologies of the synthesized materials were studied by field emission scanning electron microscope. The optical properties of the obtained materials showed that the materials had absorption in ultraviolet–visible light region. Direct optical band gap energies data of the obtained materials indicated that there are two band structure ranges. A strong band structure was in the range of 2.7 to 2.8 eV. The weak band structure was in the range of 1.8 to 2.0 eV. The photocatalytic performance of MgFe2O4 was also investigated for the degradation of Malachite Green (MG) in aqueous solution under direct visible light irradiation (Light power and colour: 40 W and white, respectively). The optimum conditions were obtained by design expert software for S3. It was found that the optimum conditions were 0.09 mL of H2O2, 28 mg of catalyst, and 40 min reaction time. The initial volume and concentration of MG solution were 60 mL and 70 ppm, respectively. It was found that MgFe2O4 had excellent efficiency under the optimized conditions at the presence of direct visible light irradiation. The degradation yield in the optimized conditions was 100%. According to the Langmuir–Hinshelwood (L–H) kinetic model, the kinetic degradation of MG followed a pseudo-first order kinetic model. The apparent rate constant (kapp) and correlation coefficient (R2) values were 0.1367 min−1 and 0.9225, respectively.

Synergetic effect of Fe2O3 and BiVO4 as photocatalyst nanocomposites for improved photo-Fenton catalytic activity

Photo-Fenton reactions and the related functional nanomaterials have been widely studied for applications in wastewater treatment industry. Herein, visible-light-responsive Fe2O3 nanoparticle-decorated BiVO4 nanoplates were designed and successfully prepared through a one-pot hydrothermal route. The as-prepared Fe2O3/BiVO4 nanocomposites exhibit excellent photo-Fenton catalytic activity toward the discoloration of methylene blue (MB) and Rhodamine B (RhB) dye molecules in the presence of H2O2. The experimental results indicate that nearly 100% of MB (100 mL, 10 mg L−1) and RhB (100 mL, 5 mg L−1) dye molecules are degraded in the presence of 1 g L−1 Fe2O3/BiVO4-1 (FB-1) photo-Fenton catalyst and 0.5 mL of H2O2 within 20 min. The Fe2O3/BiVO4 Fenton photocatalyst also demonstrates high reusability under visible light irradiation with λ ≥ 420 nm. The photoinduced electrons on the conduction band of BiVO4 nanoplates can move toward the surface of Fe2O3/BiVO4 to accelerate the reduction of Fe3+; then, the as-formed Fe2+ ions on the surface of the catalyst greatly enhance the decomposition of H2O2 to form reactive ·OH species for the use in photodegradation of MB and RhB dye molecules. The synergetic effect of Fe2O3 and BiVO4 reported in this work might provide more opportunity to fabricate other novel semiconductor-based Fenton nanocomposites for contamination treatments in wastewater.

Preparation of Ag/Fe3O4/graphene composites for wastewater removal via the photo-Fenton reaction

In this study, Ag/Fe3O4/graphene composites were used as catalysts for the removal of wastewater via the photo-Fenton reaction. The Ag/Fe3O4/graphene composites were successfully synthesized by the hydrothermal method. The Ag content was varied from 15 and 25 wt%. The structural properties of the samples were investigated by X-ray diffraction and Raman spectroscopy, and their magnetic properties were examined using a vibrating sample magnetometer. Structural analysis revealed the presence of an inverse-cubic spinel structure corresponding to Fe3O4. and a cubic structure corresponding to Ag. The presence of graphene was confirmed by the presence of the D- and G-bands at 1300 and 1500 cm−1 in the Raman spectra, respectively, and the magnetic properties of the samples indicated that Ag/Fe3O4/graphene exhibits a ferromagnetic behavior at room temperature. The photo-Fenton reaction was examined in terms of the degradation of methylene blue from an aqueous solution. Control experiments were carried out to investigate the effects of the H2O2, content and solution pH. The maximum degradation of methylene blue was observed with 4 mL of H2O2, and at pH 13, reflecting that Ag/Fe3O4/graphene composites demonstrate promise for wastewater removal via the photo-Fenton process.