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The amorphous SrTiO 3 - crystalline PbS heterojunctions were prepared through different weight percentages of PbS (5 and 10%) to promote the photocatalytic water splitting. The amorphous SrTiO 3 exhibits the combination of the hexagonal cone and nanoparticle like morphology. Similarly, the crystalline PbS shows nanoparticle like morphology. The XRD and TEM results further confirm the amorphous SrTiO 3 -crystalline PbS heterojunction formation. The EDS and XPS analysis confirm the presence of SrTiO 3 –PbS heterojunction. The SrTiO 3 –PbS heterojunction inhibits the self-trapped excitons recombination. The formation of amorphous-crystalline heterojunction suppress the electron transfer resistance which effectively reduces the charge carrier recombination. The SrTiO 3 –PbS (5%) shows efficient photocatalytic hydrogen production of 5.9 mmol g−1h−1 under ultraviolet irradiation. • Amorphous SrTiO 3 - crystalline PbS heterojunctions were synthesised with varied PbS concentrations (5 and 10%). • XRD and TEM analysis confirms the formation of amorphous SrTiO 3 - crystalline PbS heterojunction. • SrTiO 3 -PbS heterojunction inhibits the self-trapped excitons recombination and electron transfer resistance. • SrTiO 3 -PbS heterojunction enhance the photo generated electron transaction and hydrogen production efficiency. [ABSTRACT FROM AUTHOR]

This study attempted to manage the food waste and soybean curd residue generated in Taiwan's National Ilan University by black soldier fly-aided co-composting. The food waste and soybean curd residue were co-composted with rice husk as a bulking agent in 4:1 ratio and 0.42 mg BSF/g waste. The higher organic matter degradation of 31.9% was found in Container B (black soldier flies aided food waste and rice husk co-composting) with a rate constant of 0.14 d−1. In Container D (black soldier flies aided soybean curd residue and rice husk co-composting), the organic matter degradation of 29.4% was found with a rate constant of 0.29 d−1. The matured compost of 6.02 kg was obtained from 20 kg of food waste, while 5.83 kg of matured compost was generated from 20 kg of soybean curd residue. The physico-chemical parameters of the final matured compost were in the favorable range of Taiwan's compost standards. The germination index was 188.6% and 194.78% in Containers B and D, respectively. The present study will expand the application of BSF at the institutional level which prove to be a feasible solution for rapid, clean, and efficient composting of post-consumer food wastes. [ABSTRACT FROM AUTHOR]

Artificial lightweight aggregate (LWA) is produced using water reservoir sediment, spent glass, and diatomaceous earth in various compositions and sintering temperatures between 1020°C and 1110°C. This study prepared aggregate samples whose physical properties included bloating index (BI), water absorption capacity (WAC), apparent density, and compressive strength. Results showed that the morphology of the external aggregated samples, the number of pores increased as the sintering temperature rose, while the water adsorption capacity decreased with the increasing sintering temperature. Apparent density generally decreased with an increasing fraction of waste glass (WG) because average particle size of the WG was larger than spent diatomaceous earth, and water reservoir sediment. Furthermore, LWA with lower apparent density corresponded to a higher BI. According to analysis results, formulations of water reservoir sediment 50%, WG 40%, and spent diatomaceous earth 10% and water reservoir sediment 40%, WG 40%, and spent diatomaceous earth 20% aggregated samples can be used to produce artificial LWA for use as structural concrete. [ABSTRACT FROM AUTHOR]

This study presents the first attempt at employing catalytic biochar to remove ground-level ozone at ambient temperature. With the increase in human activity, ozone has become a critical inorganic pollutant that needs to be addressed, using more sustainable methods. Fe- and Mn-impregnated catalytic biochars were prepared from a sugarcane feedstock via the wet impregnation method and pyrolysis at various temperatures, where the optimum value was determined to be 550 °C. The metal-impregnated biochar samples demonstrated enhanced surface areas and pore volumes compared with the pristine biochar (SCB550), resulting in improved ozone-adsorption capacity. SCB550-Fe exhibited an ozone-adsorption capacity of 52.1 mg/g at 20 ppm, which was approximately four times higher than that of SCB550. SCB550-Fe demonstrated superior ozone-removal performance compared to SCB550-Mn; 122 mg/g capacity as opposed to 116.2 mg/g at 80 ppm, respectively. Isothermal and kinetic modeling are also presented to suggest a plausible mechanism of ozone removal by catalytic biochar. This includes physical adsorption, complexation, electrostatic interaction, and electron transfer during the redox reaction between ozone and metals. Overall, this study should provide preliminary insights into ozone removal using biochar and promote further research regarding material optimization and kinetic studies. [ABSTRACT FROM AUTHOR]

This study prepares a novel phosphorene (PN) and loads it onto TiO2 to fabricate PN-TiO2 and effectively photodegrade the hydrophobic environmental hormone 17β-estradiol in aqueous solutions. The effect of the PN on degradation efficiency is systematically investigated. It is observed that the doping of TiO2 with PN significantly enhances its photocatalytic and adsorption properties compared with that in the absence of PN; that is, the addition improves the adsorption capability of the composite. The optimal PN weight content is found to be 0.5%. The performance of the PN-TiO2 photocatalyst in degrading E2 is around 67.5%. However, its photodegradation efficiency gradually decreases when the PN content is further increased. This optimal PN content directly suggests synergistic interactions affecting the photodegrading efficiency. Compared with other PN-based photocatalysts mentioned in the literature, this PN-based material possesses striking advantages, such as higher energy efficiency, greater removal capacity, and superior cost-effectiveness. Further, the decrease in the biotoxicity of the water after treatment is evident in observing the development of zebrafish embryos. The studies of the catalyst performed on the zebrafish show that it results in a higher mortality rate at 96 h with a superior hatching rate and healthy fish development. In summary, the prepared PN-based materials exhibited promising photocatalytic capabilities for the removal and biotoxicity reduction of 17β-estradiol in aqueous solutions. [ABSTRACT FROM AUTHOR]

A well‐established electrode modifier, i. e. carboxylic acid (CA) functionalized‐multiwalled carbon nanotubes (f‐MWCNT), and a less explored safranin O (SFO) were fabricated on cuboidal graphite electrodes to develop two different voltammetric sensors for norfloxacin's electrochemical detection. The developed CA f‐MWCNT/graphite electrode and SFO/graphite showed a linear range of 3.10×10−7 to 3.13×10−5 M and 2.50×10−8 to 4.06×10−7 M with a limit of detection of 1.60×10−8 and 4.80×10−9 M, respectively. The practical applicability was tested in the spiked hospital wastewater, milk, and orange juice. It showed that the SFO could be a potential modifier for rapid, simple, and sensitive voltammetric detection of norfloxacin. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of acetaminophen (Ace) in water was studied using Zeolite Socony Mobil-5 (ZSM-5) supported TiO 2 materials, which were synthesized using a sol–gel method. The structural features of the photocatalysts were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and surface area (BET) measurements. The best loading content of TiO 2 over ZSM-5 was 40 wt% and the initial concentration of Ace was controlled at 15 mg L −1 with low intensity irradiations of 0.97 mW cm −2 , the degradation rate can reach to 96.6% after 180 min irradiation. Hydroxylation and photolysis were proposed as the initial step for Ace degradation. Main reaction intermediates and products were identified by GC–MS analysis. Additionally, the material was regenerated four times, while the degradation of Ace remained at a higher level of approximately 90%. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are common organic pollutants that can cause adverse effects on human health. Treatment techniques, including photocatalytic oxidation, have been studied to remediate VOCs. Acetone was used as a model pollutant to investigate the photocatalytic degradation performance of electrospun photocatalytic nanofibers with synthesized flower-like titanium dioxide (F-TiO2) and cellulose acetate (CA). The synthesized F-TiO2 and photocatalytic nanofibers were characterized using FE-SEM, XRD, FTIR, UVVis, XPS, and a pore size and porosity analyzer. The addition of F-TiO2 decreases the diameter of the nanofibers. The photocatalytic degradation performance test showed an enhanced acetone degradation efficiency on F-TiO2/CA photocatalytic nanofibers (FT-CFs), with an up to 95.0% acetone degradation efficiency under optimum conditions, over P25 TiO2/CA photocatalytic nanofibers (T-CFs). The filtration efficiency of 3.0%FT-CF reached 99.9% with a filter basis weight of 0.660 g m−2 and face velocity of 5.0 cm−1 s. The filtration and photocatalytic degradation cycle tests revealed excellent reusability, with 97% particle filtration and no sign of material deterioration. Moreover, the biodegradability tests showed that the material can biodegrade in water and in soil for 30 and 40 days, respectively. This study demonstrates that electrospun FT-CFs exhibit exceptional photocatalytic degradation of acetone, a high filtration efficiency, excellent reusability, and biodegradability, making them a promising solution for VOC remediation. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the toxicity of various pollutant species from motorcycle exhaust via dose–response analysis and margin of safety using Escherichia coli DH5α. The toxicity evaluation of the major components of motorcycle exhaust volatile organic compounds (VOCs), collected with impinger, and polycyclic aromatic hydrocarbons (PAHs), collected with filter and XAD-2, is essential to determine emission standards for motorcycles. The toxicity of benzene (B), toluene (T), ethyl benzene (E) and xylene (X) was selected for comparison as standard VOCs emitted from motorcycles. In addition, three types of reformulated gasoline (high oxygenate and high benzene content (No. 1), low oxygen and high benzene (No. 2), and low oxygen and low benzene (No. 3) were prepared to reveal combined toxicity of individual compositions. Motorcycle exhaust is significantly more toxic than BTEX due to the highly toxic VOCs generated from incomplete combustion. Overall toxicity evaluation showed that the toxicity, indicated as EC50, was approximately as follows: PAHs>two-stroke engines>four-stroke engines>BTEX. [Copyright &y& Elsevier]

In order to recover valuable materials and to minimize the adverse effects of hazardous materials contained in scrap computers, a dismantling practice is commonly adopted to treat scrap computers. By using the dismantling process, both useful and hazardous materials can be manually separated and retrieved. On the basis of the properties of the retrieved materials, they can be sent to appropriate facilities for further recycling or treatment. Among the retrieved materials, the treatment of hazardous materials from cathode ray tubes (CRT) and printed circuit boards with integrated circuits have drawn considerable attention, thus implying that the proper treatment of such materials can greatly assure the successful recycling of scrap computers. For this reason, this study reviews the available technologies which can be applied to treat and recycle cathode ray tube components and printed circuit boards with integrated circuits. Actual recycling data from a scrap computer recycling plant located in Taiwan are also introduced. The data show that this recycling plant can recover 94.75wt.% and 45.99wt.% of useful materials from the main machines (i.e., CPU, power supplier, fan, IC boards, DVD drive, CD drive, hard disk, soft disk, shell casing, etc.) and monitors of scrap computers, respectively. [Copyright &y& Elsevier]

The study provides novel attempt to use an aerobic biofiltration system containing entrapped mixed microbial cells (EMMC) for removal of (CH3)3N-dominant waste gases. In the study, heterotrophic microflora-immobilized cellulose was packed into an EMMC reactor to degrade (CH3)3N. Effects of (CH3)3N inlet concentrations in continuous mode of operation at various flow rates are indicated. The result indicated that the (CH3)3N removal efficiency is higher than 90% at inlet loading below 27.2 mg N h−1 and retention time 5.3 min. In addition, the maximal mass loading to reach approximately 99% efficiency was 95.5 mg N h−1 for trimethylamine treatment. This EMMC biofiltration system also showed higher tolerance to endure fluctuations in concentrations and flow rates and still maintained in stable performance for removal. Adaptability test in response to gradual shift up and down of inlet TMA loading indicated that lack of steady-state multiplicity and hysteresis guarantees the microbial communities more precisely adapted to continuous treatment for maintaining stability. [Copyright &y& Elsevier]

Atmospheric concentrations of chlorine atom (Cl⋅), chlorine monoxide radical (ClO⋅), and hydroxyl radical (HO⋅) in the coastal marine boundary layer are estimated in this study. A steady-state approach to their concentrations in equilibrium with other atmospheric chemical species is used. Measurements of atmospheric trace species, HCl, Cl2, HCHO, H2O2, CH3OOH, CH4, CO, SO2, NO, NO2, and O3, were performed at four sites in Taiwan during the spring of 1999. The results indicate that the concentrations of the Cl⋅ atom and the ClO⋅ and HO⋅ radicals decrease significantly with cloud cover. The calculated average daytime concentrations of Cl⋅, ClO⋅, and HO⋅ are 3×105, 1×107, and 6×105 molecules/cm3, respectively. Due to the high reactivity of Cl⋅ with hydrocarbons and its concentration level competitive to that of HO⋅, Cl⋅ should be a significant sink for hydrocarbons in these cases. [Copyright &y& Elsevier]

Acetone is solvent widely used in laboratories and factories. Serious problems will occur when it is exposed to the environment. Therefore, a new design for a bimetallic metal functional group catalyst that can convert acetone into carbon dioxide and water within 250 °C was prepared, in order to effectively treat acetone and reduce the required energy. Hydrophobic Y type zeolite adsorption and low-temperature catalytic combustion were used to continuously treat acetone, and the effect of different operating parameters (including different metal loads, metal content, transformation temperature, pollutant concentration, and space velocity) on the efficiency of acetone treatment was discussed in this study. The isothermal adsorption model, kinetics, and thermodynamic model analysis were also used to establish the reaction mechanism, and to explore the factors affecting the catalyst reaction rate. The results show that the acetone conversion rate of 10-Fe1Mn1-USY reaches 90% at 400 ppm, 20,000 h−1 space velocity, and 227 °C. The kinetic behavior of the reaction between 10-Fe1Mn1-USY and acetone is more suited to the Power-rate Law model. Arrhenius equation analysis results show that the required activation energy for the reaction between 10-Fe1Mn1-USY and acetone is 70.2 kJ mol−1, and the collision frequency factor is 2.81 × 105 s−1. This reaction is an endothermic reaction, and the main reaction mechanism is surface metal oxidation. A new design for a bimetallic metal functional group catalyst that can convert acetone into carbon dioxide and water within 250 ℃ was prepared, in order to effectively treat acetone and reduce the required energy. Hydrophobic Y type zeolite adsorption and low-temperature catalytic combustion were used to continuously treat acetone, and the effect of different operating parameters on the efficiency of acetone treatment was discussed in this study. Result shown that the redox reaction between the adsorbed acetone and the active oxygen on the surface of the catalyst to generate CO2 and H2O. [ABSTRACT FROM AUTHOR]

The study investigated the synergistic effects of rGO and Pt over TiO 2 for the HER via artificial photosynthesis under UVB and visible light irradiation. The introduction of glycerol and industrial wastewater to the system as sacrificial reductants signifies that the major reaction pathway is photocatalytic partial water splitting. The material characterizations revealed successful heterojunction formation and provided insight into chemistry behind the activity of the photocatalysts. Amongst various combinations of rGO on TiO 2 , 1GNT exhibited an HER yield five times that of bare TiO 2 under UVB light. Addition of Pt led to the formation of a strong Schottky barrier at the heterojunction and consequently boosted HER performance. 1P0.5 GT presented the highest of 28.5 mmol g−1 h−1 with glycerol and 9.6 mmol g−1 h−1 with wastewater under UVB light respectively. For both binary and ternary photocatalysts, the HER performances dwindled under visible light irradiation, accentuating the insufficient activation of the TiO 2. In addition, 1PT outperformed all the other photocatalysts thereby elucidating the impression that rGO and Pt does not work well together in enhancing HER despite quenching the exciton recombination rate of TiO 2 significantly. The role of pH in the synthesis and the experiments has been discussed. Finally, the underlying mechanisms in the photodeposition and photoreformation have been proposed. • Synergistic effects of rGO & Pt over TiO 2 towards HER via artificial photosynthesis • Comprehensive characterization of as-synthesized photocatalysts. • Proposed underlying HER and Photodeposition mechanisms. • Tested glycerol & wastewater to determine HER efficiency in real world scenario. • Highly efficient photocatalyst generated up to 28.5 mmol g−1 h−1 H 2 under UVB light. [ABSTRACT FROM AUTHOR]

S–modified MXene (Ti3C2Tx@S–5) was prepared to improve the catalytic activity of MXene in the electrocatalytic degradation of tetracycline hydrochloride (TC). Here, S groups in the form of Ti–S and S–O species were anchored onto MXene, resulting in superior conductivity and surface activity. Ti3C2Tx@S–5 exhibited an excellent performance of 100% TC degradation under the conditions of 25 °C, a pH of 6, a TC concentration of 10 mg L−1, and an applied current of 20 mA. Radical quenching and EPR analyses revealed that ·O2− and 1O2 played dominant roles in Ti3C2Tx@S–5 and Ti3C2Tx systems. Furthermore, S modification promoted the triggering of ·OH and active chlorine, which contributed to the acceleration of TC degradation. The involvement of these active substances in degradation pathways was further proven. This research advances the S modification of MXene and improves TC degradation by promoting the triggering of ·OH and active chlorine, broadening the applicability of MXene material. [ABSTRACT FROM AUTHOR]

Ti-doped MCM-41 with different Si/Ti molar ratios was prepared at room temperature to degrade tetracycline antibiotics in aqueous solution. The Ti was doped into the skeleton structure of MCM-41. The photocatalytic activity of Ti-doped MCM-41 was investigated. The optimal catalyst had Si/Ti molar ratio of 25 and over 99% removal of oxytetracycline in 150 min, and the removal could maintain 98% after 5 reuses. Ions and soluble organic matters in natural water affected the degradation reaction when Ti-doped MCM-41 was used to treat simulated wastewater of chicken farms. The degradation products of oxytetracycline, tetracycline and chlortetracycline were detected by Escherichia coli DH5α and HPLC–MS/MS. No intermediate product with higher toxicity was detected. [ABSTRACT FROM AUTHOR]

The skeletal muscle progenitors' proliferation and migration are crucial stages of myogenesis. Identifying drug candidates that contribute to myogenesis can have a positive impact on atrophying muscle. The purpose of the study is to synthesize the Antrodia cinnamomea (AC)-β-cyclodextrin (BCD) inclusion complex (IC) and understand its in vitro pro-regenerative influence in murine skeletal C2C12 myoblasts. The IC was subjected to various nano-characterization studies. Fluorescent IC was synthesized to understand the cellular uptake of IC. Furthermore, 25 µg/mL, 12.5 µg/mL, and 6.25 µg/mL of IC were tested on murine C2C12 skeletal muscle cells for their anti-inflammatory, pro-migratory, and pro-proliferative action. The cellular internalization of IC occurred rapidly via pinocytosis. IC (252.6 ± 3.2 nm size and −37.24 ± 1.55 surface charge) exhibited anti-inflammatory action by suppressing the secretion of interleukin-6 and enhanced cell proliferation with promising cytocompatibility. A 12.5 μg/mL dose of IC promoted cell migration in 24 h, but the same dose of AC significantly reduced cell migration, suggesting modification by BCD. Molecular studies revealed that IC promoted C2C12 myoblasts migration by upregulating long non-coding RNA (lncRNA) NEAT-1, SYISL, and activating the pPKC/β-catenin pathway. Our study is the first report on the pro-proliferative and pro-migratory effects of BCD-modified extracts of AC. [ABSTRACT FROM AUTHOR]

Mercury is a physiological toxin released by spent fluorescent lamps (SFLs) and is considered a serious pollutant. As the world’s largest producer of fluorescent lamps, China suffers from SFL pollution because of inefficient recycling and management of SFLs. Drawing upon the most successful practices worldwide, this paper suggests the recycling of SFLs on the basis of the extended producer responsibility (EPR) system in China. Manufacturers and importers are the main parties responsible for the take-back, recycling, and disposal of SFLs in the EPR system. In view of the situation in China and to address the objectives of the EPR system, this paper recommends the implementation of a third-party take-back mode for small- and medium-scale enterprises and of a take-back mode for large enterprises to be carried out by original equipment manufacturers. This paper suggests an extended responsibility fund to finance and support the SFL recycling system and discusses in detail the different recycling network systems and fund flows of the two take-back modes. By conducting a case study, the authors determine that the subsidy rate for SFLs that a recycling company can obtain from the extended responsibility fund for recycling and disposing of lamps can be set at $1.35/kg. The authors also predict the levy level that fluorescent lamp manufacturers must submit.Implications:For policymakers, a proper and effective way to manage and recycle spent fluorescent lamps (SFLs) is necessary. The recommended system and the predicted number values of the subsidy rate and levy level can be the basis in practice. For people, the proper management measures will reduce exposure from SFLs effectively, especially the risk of exposure to mercury. For society, the measures can help increase resource utilization rate. For manufacturers, an effective extended responsibility fund will motivate them to improve processing technique and green design. [ABSTRACT FROM AUTHOR]

Co-catalyst free SrTiO3 was prepared by hydrothermal method and it's calcinated by different temperatures such as 300, 500, 700, and 900 °C to improve the photocatalytic hydrogen production. The SrTiO3 exhibits a cubic crystal structure which was revealed through X-ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) images show the combination of nano spherical-needle morphology changed into nano-cubic morphology when the temperature varied from 300 to 900 °C. Further, transmission electron microscopy (TEM) result also confirms the nano-cubic crystal structure with well-resolved edges. The elemental mapping analysis shows the Sr, Ti, O elements were distributed uniformly in the prepared SrTiO3. The X-ray photoelectron spectroscopy (XPS) confirms the presence of chemical compositions and valance state of Sr, Ti, O elements in SrTiO3. The self-trapped excitons recombination of SrTiO3 was analyzed by photoluminescence (PL) analysis. The Electrochemical Impedance Spectroscopy (EIS) analysis of SrTiO3-900 °C shows the lowest electron transfer resistance which promotes effective charge separation. Among the different catalysts, SrTiO3-900 °C gives 6.8 mmol g−1 h−1 of hydrogen under Ultra-Violet irradiation. [ABSTRACT FROM AUTHOR]

In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2nonwoven filters using electrospinning. The wires of titanium dioxide and the nonwoven binding titania nanofibers were formed using 14 kV voltage and a distance of 15 cm. A single-factor experimental method was used to investigate the effects of parameters such as initial concentration, retention time, and light source on acetone removal by nonwoven binding titania nanofibers. Furthermore, the effects of parameters such as gas pressure, particle size, initial concentration, and retention time on the removal of particulates were also assessed. The results showed that the degradation efficiency increased with decreasing initial concentrations and increasing retention time. The best operational conditions during this study for the removal of acetone using the TiO2nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and ultraviolet (UV) light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained. In addition, 90% particulate matter removal efficiency was reached when the particulate size was greater than 200 nm and the reaction time was longer than 5 minutes. The prepared TiO2/nanofiber has good performance for volatile organic compounds (VOCs) and particulate removal at the same time. Implications:In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2 nonwoven filters using electrospinning. The results showed that the optimum operating conditions for the removal of acetone using the TiO2 nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and UV light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained. [ABSTRACT FROM AUTHOR]

Abstract: This study used various biocarriers (e.g., porites corals, Biolite™, porous ceramic filter media (PCFM)) to immobilize cells in fixed bed bioreactor (FBB) for wastewater decolorization. As prior studies proposed, an innovative graphical method of constant-slope isoclines to determine maximal allowable treatment capacity (MATC) was used as screening criteria for feasibility of packing matrices of immobilized cell systems (ICSs). Moreover, detailed inspection upon physical and chemical characteristics of packing matrices was also carried out to confirm the consistency of MTAC. The result of isocline analysis was in parallel with physical characteristics of biocarriers (i.e., porites coral>Biolite™>PCFM). This first-attempt study successfully provided perspective in general terms to assess how the selected supporting materials were suitable to be packing matrices of ICSs for industrial applications (e.g., wastewater treatment). [Copyright &y& Elsevier]

Abstract: Mesoporous MCM-41 was synthesized using cetyltrimethyl ammonium bromide (CTAB) as a cationic surfactant and spent glass as the silica source. The prepared samples were characterized by X-ray powder diffraction (XRD), nitrogen adsorption–desorption analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope–energy dispersive spectroscopy (SEM–EDS). The results showed that the surface area, pore volume and pore diameter could be up to 1328m2 g−1, 0.82cm3 g−1 and 2.62nm, respectively. The toluene adsorption capacity of MCM-41 (from pure chemical sources) at different concentrations could be calculated to be about 60, 104, 195 and 262mgg−1, respectively. In terms of breakthrough curve shape, the experimental results for G-MCM (from spent glass) were similar to those for MCM-41. Furthermore, the adsorption capacities of MCM-41 and G-MCM (mesoporous silica materials synthesized from spent glass) were almost the same. In this study, the effects of operation parameters, such as contact time and mixture concentration, on adsorption performance were also assessed. [Copyright &y& Elsevier]

Aqueous glyphosate (GLYP) was voltammetrically detected using a Cu‐(poly)pyrrole composite electrochemically deposited on activated carbon fiber for the first time in a single‐step method. Differential pulse voltammetry indicated good linearity (R2 = 0.9902) in the response over 0.02–12 mg L−1 range, with a low limit of detection (0.01 mg L−1). The sensor exhibited reproducibility for soil and fruit samples (RSD values = 2.41 and 3.87%, respectively). The response showed repeatability over 100 consecutive measurements. The response was also unaffected by the interfering substances containing the same functional groups as in GLYP and its metabolite. The method described in this study is facile. [ABSTRACT FROM AUTHOR]

Abstract: This study explored dye decolorization and bioelectricity generation of indigenous Proteus hauseri ZMd44 for dye-bearing wastewater treatment. Chemical structures of azo dyes apparently affected the performance of dye biodecolorization. Additions of diazo dye C.I. reactive blue 160 (RBu160) stimulated simultaneous dye decolorization and bioelectricity generation of ZMd44 in single chamber microbial fuel cells (MFCs). However, high-level additions of RBu160 repressed capabilities of power production in MFC due to competition of electrons used for reductive decolorization. Decolorized intermediates of RBu160-phenyl methadiamine and 5-sulfoanthranilic acid as electron shuttles might mediate electron transport for current generation in MFC. [Copyright &y& Elsevier]

Abstract: The goal of this study is to find out the exhaust emissions differences produced by different kinds of fatty acid methyl esters (FAME) derived from used cooking oils and animal fats, as well as the importance of the purification step in exhaust emissions production. A total of 120L of waste vegetable oil and 30L of waste frying oil were collected and converted into three batches of FAME. There were two batches of FAME produced from waste vegetable oil (B01 and B02), and one batch of FAME produced by mixing 2% of waste frying oil with waste vegetable oil (B03). The FAMEs used in this study had higher density, kinematic viscosity, and flash point, but a lower gross heating value, when compared to the premium diesel. The B01 engine produced higher CO formation and the diesel-fuelled engine produced higher CO than the B02 and B03 did for engine speeds higher than 1400rpm. Most of the FAME fuels produced higher CO2 than the diesel fuel did. The FAME fuels emitted higher NO x and PM, but lower SO2, than the diesel fuel. C n H2n+2, diphenyl sulfone (C12H10O2S), and diethyl phthalate (C12H14O4) can be selected as the character index for the combustion of FAME. [Copyright &y& Elsevier]

Abstract: In this study, wasted cooking oil from restaurants was used to produce neat (pure) biodiesel through transesterification, and this converted biodiesel was then used to prepare biodiesel/diesel blends. The goal of this study was to compare the trace formation from the exhaust tail gas of a diesel engine when operated using the different fuel type: neat biodiesel, biodiesel/diesel blends, and normal diesel fuels. B20 produced the lowest CO concentration for all engine speeds. B50 produced higher CO2 than other fuels for all engine speeds, except at 2000rpm where B20 gave the highest. The biodiesel and biodiesel/diesel blend fuels produced higher NO x for various engine speeds as expected. SO2 formation not only showed an increasing trend with increased engine speed but also showed an increasing trend as the percentage of diesel increased in the fuels. Among the collected data, the PM concentrations from B100 engines were higher than from other fuelled engines for the tested engine speed and most biodiesel-contained fuels produced higher PM than the pure diesel fuel did. Overall, we may conclude that B20 and B50 are the optimum fuel blends. The species of trace formation in the biodiesel-contained fuelled engine exhaust were mainly C n H2n+2, DEP, and DPS. For the B100, B80, B50, and D fuelled engines, C15H32 was the dominant species for all engine speeds, while squalene (C30H50) was the dominant for B20. DEP was only observed in the B100, B80, and B50 fuelled engines in this study. The D fuelled engine showed a higher DPS production for engine speeds higher than 1200rpm. [Copyright &y& Elsevier]

Abstract: This study evaluated the performance of photo-Fenton reaction initiated by the UV irradiation with H2O2/Fe3+, denoted as UV/H2O2/Fe3+, to decompose di-n-butyl phthalate (DBP) in the aqueous solution. The concentration of total organic carbon (TOC) was chosen as a mineralization index of the decomposition of DBP by the UV/H2O2/Fe3+ process. A second-order kinetic model with respect to TOC was adequately adopted to represent the mineralization of DBP by the UV/H2O2/Fe3+ process. The experimental results of this study suggested that the dosages with 4.74×10−5 molmin−1 L−1 H2O2 and initial Fe3+ loading concentration of 4.50×10−4 molL−1 in the solution at pH 3.0 with 120μWcm−2 UV (312nm) provided the optimal operation conditions for the mineralization of DBP (5mgL−1) yielding a 92.4% mineralization efficiency at 90min reaction time. [Copyright &y& Elsevier]

Abstract: Basic oxygen furnace slag (BOF slag) is a solid waste arisen from the steel making process. FeO is one of the major components of BOF slag. The FeO-containing property of BOF slag makes it possible to catalyze the Fenton reaction. Reactive Black 5 (RB5) dye is chosen as the target compound in this study. This study has investigated the catalytic performance of BOF slag on the Fenton reaction to decompose RB5 in aqueous solution. A first-order kinetic model with respect to TOC was adopted to explain the mineralization of RB5 by the H2O2/BOF slag process. The experimental results in this study suggested that dosage with 1.49×10−4 Mmin−1 H2O2 and 12.5g l−1 BOF slag in the solution at pH 2 provided the optimal operation conditions for the mineralization of RB5 yielding a 51.2% treatment efficiency at 100min reaction time, and complete decoloration can be achieved within 30min reaction time. The H2O2/Fe2+ ratio was then determined to be 6.06:1. [Copyright &y& Elsevier]

• Electro sorption of copper phthalocyanine over activated carbon fibers. • Electro-oxidative degradation of glyphosate using a carbon and copper electrode. • Central composite design for electro-oxidation of glyphosate. • Response surface methodology for reaction parameter optimization. • Kinetic assessment of glyphosate degradation during electro-oxidation. A novel approach is proposed in this study for degrading aqueous glyphosate (GLYP) efficiently via electro-oxidation (EO) using a novel copper phthalocyanine (CuPc)-dispersed activated carbon fiber (ACF) electrode. Green synthesis of the CuPc-ACF electrode was achieved by electro-sorption process through oxidation-reduction of the Cu species, using cyclic voltammetry, also for the first time. The prepared electrode was directly applied to degrade the aqueous recalcitrant pollutant without supplementation of an electrolyte and external source of oxidant. Operating parameters of the EO system were optimized via response surface methodology (RSM) based on central composite design using performance index of the area under the curve (AUC). A complete degradation of a synthetic GLYP solution at high concentration (1000 mg L−1) was indicated at the optimized pH and biased potential of 11 and 2.5 V (vs Ag/AgCl), respectively. Kinetic assessment of the experimental data revealed a threshold voltage between 1.5 and 2.0 V required to trigger an effective and irreversible degradation of the aminomethyl phosphonic acid (AMPA) intermediate. The kinetics for degradation of GLYP was proposed via two pathways: a consecutive first-order reversible or an irreversible reaction forming the AMPA intermediate and a parallel reaction forming final transformed products. The study indicated a green route for the synthesis of the CuPc-ACF electrode for complete degradation of GLYP using EO as a green technology. [ABSTRACT FROM AUTHOR]

Graphene is a one-atom-thick sheet, possessing a high electron mobility, constructed from sp2-bonded carbon atoms. Here, we hypothesize that graphene functions as a conductive material to promote anaerobic ammonium oxidation coupled with Fe(III) reduction (Feammox) in mangrove sediments slurries. In this study, graphene and 9,10-anthraquinone-2-sulfonate (AQS) were both investigated using a nitrogen isotope tracing technique. Graphene and AQS addition increased the Feammox rates by 31% and 56%. Graphene also increased the Fe(III) reduction rate by 43%, but Feammox-associated Fe(III) reduction accounted for only 1.5–4.9% of the total Fe(III) reduction. Graphene may have behaved as a conductive bridge to promote electron transfer to the Fe(III) acceptor in the Feammox process; however, the mechanisms by which graphene and AQS stimulate Feammox are different. • Feammox was detected in mangrove sediments using an isotope tracing technique. • Feammox contributed 1.5–4.9% of total Fe(III) reduction. • Graphene behaved as a conductive bridge to promote the Feammox process. [ABSTRACT FROM AUTHOR]

Abstract This first-attempt study revealed optimal strategy to supplement extracts of polyphenolics-abundant medicinal herbs and Camellia tea as electron shuttles (ESs) for stimulating bioenergy generation in microbial fuel cells (MFCs). Apparently, Camellia sinensis (L.) Kuntze and Syzygium aromaticum were promising electroactive ESs. Moderate temperature (ca. 65 °C) and slightly alkali pHs (∼10) were electrochemically feasible conditions for herbal extraction. Optimal contents of polyphenolics-rich herbs and tea extracts with maximal electrochemical activities could be stably obtained. Power density of MFC supplemented with Camellia green tea extract could significantly increase ca. 176%, suggesting that green tea extract would be the most appropriate ESs. Total phenolic contents and electron shuttling capabilities were all electrochemically associated. In addition, chemical structure strongly affected whether antioxidant activities of polyphenolics-abundant herbal extracts could be reversibly switched to be electron-shuttling capabilities (e.g., substitution patterns). Hydroxyl substiutuents ortho or para to each other were very likely promising for electron-shuttling, but not for meta substituents. Moreover, bioelectrochemical treatment upon medicinal herbal extracts (e.g., cyclic electron-donating and withdrawing processes) might be inevitably needed for toxicity attenuation to fully express bioenergy-shuttling activities. Highlights • Unveil natural electron shuttles (ESs) from herbal and tea extracts for MFCs. • Disclose operation strategy to convert polyphenolic antioxidants to be ESs. • Decipher biostimulation of natural ES catalysts to power generation in MFCs. [ABSTRACT FROM AUTHOR]

Multilayer ZnO nanoflowers were synthesized through a simple precipitation method and characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectra (XPS) and nitrogen absorption-desorption techniques. The FE-SEM images show the integrated morphology of an individual flower-like ZnO nanostructure, which is made of nano-platelets with uniform thickness (20–30 nm). The average pore size and Brunauer-Emmet-Teller (BET) surface area of the as-synthesized ZnO were 27.25 nm and 13.53 m 2 /g. The sonocatalytic ability of the prepared samples was evaluated through norfloxacin (NF) degradation in an aqueous system using ultrasound (US) irradiation. To improve degradation efficiency, peroxydisulfate (Na 2 S 2 O 8 ) was introduced to develop a US/ZnO/peroxydisulfate system, which exhibited an excellent synergistic effect. The effects of ZnO dosage, Na 2 S 2 O 8 concentration, pH, and initial NF concentration were studied to determine the performances of the US/ZnO/peroxydisulfate process. Corresponding results showed that NF degradation rate increased with the increase of ZnO dosage but decreased with the increase of initial NF concentration. Under the optimal Na 2 S 2 O 8 concentration of 0.1 g L −1 at pH 9, the best degradation efficiency can be achieved. Moreover, based on the scavenging experiment results and literatures, NF degradation through US/ZnO/peroxydisulfate system is majorly induced by OH and SO 4 − radicals. [ABSTRACT FROM AUTHOR]

A novel category of improved performance membrane consisting of a hydrophobic mat and a hydrophilic electrospun layer for membrane distillation (MD) application has been presented. The nanofibrous non-woven layer was fabricated by electrospinning of polyvinylalcohol (PVA) incorporated with Triton X-100 directly onto the polypropylene (PP) mat. To render the membrane distillation process effective in terms of high permeate flux and salt rejection %, the concept of dual layer membrane is utilized with hydrophobic PP mat on top and hydrophilic PVA layer on bottom. In this study, PVA nanofibrous layer has been fabricated by incorporating non-ionic surfactant Triton X-100 for uniformity and homogeneity in fiber diameter. Additionally, the PP mat acts as a top support layer and PVA-TX nanofiber acts as base layer which absorb the water molecules (condensed vapour), that enhances the vapour flux across the membrane. The modified bilayer PP/PVA-TX membranes were characterized by the pore size distribution, permeate flux, and rejection %, then compared with original PP mat. The salt rejection of the dual layered PP/PVA-TX membrane showed > 99% and still maintained 2 times higher permeate flux compared to PP membrane for long term operation of 15 h. [ABSTRACT FROM AUTHOR]

This study synthesizes colloidal silver triangular nanoprisms via dual-reduction method. The particle morphology is controlled by changing the silver nitrate and polyvinylpyrrolidone concentrations. The triangular silver and spherical silver colloids are combined with TiO 2 powder for methylene blue (MB) photodegradation in visible light. Comparisons between the spherical Ag (S-Ag) and experimental results show that the triangular silver (T-Ag) significantly promotes MB degradation under visible light, which contributes to the surface plasmon resonance effect on the Ag triangular nanoprisms. [ABSTRACT FROM AUTHOR]

In this study, a one-step solid dispersion method was used to synthesize titanium dioxide (TiO 2 )/Zeolite Socony Mobil-5 (ZSM-5) composites with substantially reduced time and energy consumption. A degradation efficiency of more than 95% was achieved within 10 min using 50% PTZ (synthesized TiO 2 /ZSM-5 composites with TiO 2 contents of 50 wt% loaded on ZSM-5) at pH 7 and 25 °C. The possible degradation pathway of azo-dye Reactive Black 5 (RB5) was investigated using gas chromatography–mass spectrometry and ion chromatography (IC). The bonds between the N atoms and naphthalene groups are likely attacked first and cleaved by hydroxyl radicals, ultimately resulting in the decolorization and mineralization of the azo dye. A comparative assessment of the characteristics of abiotic and biotic dye decolorization was completed. In addition, the toxicity effects of the degradation intermediates of azo-dye RB5 on cellular respiratory activity were analyzed. The bio-toxicity results showed that the decay rate constants of CO 2 production from the azo-dye RB5 samples at different degradation times increased initially and subsequently decreased, indicating that intermediates of higher toxicity could adhere to the catalyst surface and gradually destroyed by further photocatalytic oxidation. Additionally, EDTA (hole scavengers) and t -BuOH (radical scavengers) were used to detect the main active oxidative species in the system. The results showed that the hydroxyl radicals are the main oxidation species in the photocatalytic process. [ABSTRACT FROM AUTHOR]

Using wastewater as sacrificial reagent to transfer solar energy and water as clean energy has attracted significant attention because of increasing concerns on environmental pollution and depletion of fossil fuels. In this study, wastewater from terephthalic acid preparation process was used as sacrificial reagent, and raw components and intermediates were identified by GC–MS, IC, and TOC analyzer. The characterizations of the catalyst were analyzed by XRD, TEM, and XPS. Results showed that the metal and metallic ions (Fe 2+ and Fe) in wastewater were more feasible for electron provision than organics. The final products of Fe 3+ were also confirmed by XPS on the surface of the catalyst. By contrast, the rate of photocatalytic H 2 production did not changed with the addition of terephthalic acid. The H 2 production rate could reach 1.8 mmol g −1 h −1 through the use of wastewater and acetic acid as sacrificial reagents. [ABSTRACT FROM AUTHOR]

In this study, we found a novel property of graphene and KBrO 3 as double and enhanced collaborative catalysts to degrade amoxicillin (AMX) on the photocatalytic behavior of TiO 2 nanotubes under UVA light irradiation. The synthesis of graphene-TiO 2 nanotubes (GN-TNT) is a necessary first step. AMX can be photo-degraded with GN-TNT, but its degradation rate reaches nearly 100% with the addition of KBrO 3 , which has two roles in photo-degradation. Its first and more important function is the prevention of electron-hole recombination by acting as electron acceptor. Its second function is its direct participation as oxidant in the degradation of AMX. The effects of GN loading, KBrO 3 initial concentration, and AMX concentration on photocatalytic activity are explored in this study. Results of the kinetic study also show that degradation can be expressed by a first-order reaction kinetic model. The degradation mechanism of photocatalytic activity and the role of KBrO 3 are also discussed. [ABSTRACT FROM AUTHOR]

Norfloxacin (NF) is an effective antimicrobial drug that poses a threat to human health because of its environmental residues. In this research, ZnO nanoflowers and triangular silver nanoplates (T-Ag) were synthesized using a facile sol–gel method. The synergistic photocatalytic effects of the adding different triangular silver nanoplates concentration over ZnO nanoflowers on the NF removal under visible light was studied for the first time. Photodegradation results demonstrated that T-Ag could significantly enhance the activity of ZnO nanoflowers. The degradation efficiency of NF by T-Ag/ZnO nanoflowers was affected in the different water matrices, including ultra-pure, tap, and river water. The effects of the dosage of ZnO nanoflowers, initial NF concentration, and pH on the photocatalytic activity of ZnO nanoflowers were also explored. The results show that the highest rate constant for the degradation of NF is obtained with 1 mg L −1 of T-Ag, 0.1 g L −1 of ZnO, initial NF concentration of 10 mg L −1 , and pH of 11 in ultra-pure water. The possible mechanism of the photocatalytic degradation of NF using T-Ag/ZnO nanoflowers through the addition of scavenger agents (i.e., EDTA and methanol) was also studied. [ABSTRACT FROM AUTHOR]

Different kinds of graphene (GN)/titania nanocomposites using graphene and P25 or Titanium (IV) n-butoxide (TBOT) as precursors were prepared with hydrothermal method. To investigate the differences of the photocatalytic properties of composites with various shapes of titanium dioxide (TiO, three types of TiO2, including titanium nanotubes (TNT), titanium nanosheets (TNS) and titanium nanoparticles (TNP) were successfully prepared and combined with GN to form the composites. The prepared composites were confirmed by Ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray Photoelectron Spectroscopy (XPS), and transmission electron microscopy (TEM), etc. Photocatalytic activities of composites were carried out by the degradation of Reactive Black 5 (RBk5) and Norfloxacin (NFXC) under the radiation of UV lamp. Results indicate that the differences in the TiO2 morphology of the composites greatly influence the catalytic properties. In addition, the heterojunction between graphene and TiO2 also play an important role in the photocatalytic abilities of composites. In this study, it can be seen that the prepared composites exhibit higher photocatalytic activity including excellent adsorption capacity and photo-degradation ability than P25. The photocatalytic activity of GN-TNS is higher than that of GN-TiO2 and GN-TNT. In the current study, three different mophology TiO2 with GN composites had been successfully fabricated by varying the temperature, solvent, and reaction time of the hydrothermal process. The photocatalytic activities of these composites were carried out by the degradation of RBk5 and NFXC under the radiation of UV lamp. The results show that the reactions of NFXC and RBK5 are both obey the first-order relationship, and GN-TNS exhibited the most excellent photocatalytic performance. [ABSTRACT FROM AUTHOR]

Triangular silver nanoplate-coated flower-like ZnO nanostructures were successfully fabricated via a facile hydrothermal method combined with a dual reduction method. The morphology, composition, and structural and optical properties of the as-synthesized materials were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), UV–vis absorption spectra, X-ray diffraction (XRD), and photoluminescence (PL) spectrum. Results show that the morphology of ZnO and Ag were flower-like and triangular nanoplate, respectively. Triangular silver nanoplates exhibit unique surface plasmon resonance (SPR) absorption spectra, and the PL intensity of flower-like ZnO decreased by coating triangular silver nanoplates. In addition, the growth process and possible mechanism of flower-like ZnO and triangular silver nanoplates are discussed in certain detail. [ABSTRACT FROM AUTHOR]

This first-attempt study revealed mixture design of experiments to obtain the most promising composites of TiO 2 loaded on zeolite and graphene for maximal photocatalytic degradation of oxytetracycline (OTC). The optimal weight ratio of graphene, titanium dioxide (TiO 2 ), and zeolite was 1:8:1 determined via experimental design of simplex lattice mixture. The composite material was characterized by XRD, UV–vis, TEM and EDS analysis. The findings showed the composite material had a higher stability and a stronger absorption of the visible light. In addition, it was uniformly dispersed with promising adsorption characteristics. OTC was used as model toxicant to evaluate the photodegradation efficiency of the GTZ (1:8:1). At optimal operating conditions (i.e., pH 7 and 25 °C), complete degradation (ca. 100%) was achieved in 180 min. The biotoxicity of the degraded intermediates of OTC on cell growth of Escherichia coli DH5α were also assayed. After 180 min photocatalytic treatment, OTC solution treated by GTZ (1:8:1) showed insignificant biotoxicity to receptor DH5α cells. Furthermore, EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to detect the main active oxidative species in the system. The results showed that the holes are the main oxidation species in the photocatalytic process. [ABSTRACT FROM AUTHOR]

This study tended to decipher the mechanism of photo degradation of azo dyes, which bond was favorable to be broken for application of wastewater decolorization. That is, from chemical structure perspective, the critical substituents to affect electron donor/acceptor for dye degradation would be identified in this research. The model reactive blacks (RB5), reactive blue 171 (RB171) and reactive red 198 (RR198) were degraded by graphene loaded TiO 2 , indicating how the electron withdrawing and releasing groups affect azo dye degradability. The byproducts and intermediate products were analyzed by ultraviolet–visible spectroscopy (UV–vis), gas chromatography–mass spectrometry (GC–MS) and ion chromatography (IC). Furthermore, the radicals involved in the reaction were found by electron paramagnetic resonance (ESR) to confirm the main oxidized species of hydroxyl radicals rather than the light generated positive holes. The finding revealed that the breakages of the bonds were due to the electron density changes around the bonds. This principle can be applicable not only for RB5 degradation, but also for reactive blue 171 (RB171), reactive red 198 (RR198) and some other textile dyes. [ABSTRACT FROM AUTHOR]

The cement industry is the most energy intensive of Taiwan's manufacturing industries. This paper presents a case study of the greenhouse gas (GHG) inventory in Taiwan's cement industry, which includes an analysis of GHG emission intensity (EI) and the testing of raw meal calcination. The GHG inventory analysis results show that direct GHG emissions (Scope 1) are the largest emission source of the study subject, the H plant. As regards the EI analysis results of Taiwan's cement plants, only one cement plant (H plant) meets the EI limit announced by the Environmental Protection Administration (EPA) of Taiwan. According to the calcination test, the major calcination reaction occurs in the 700–900°C temperature range and accounts for nearly 87% of total CO2emissions. Finally, a modified and feasible process is proposed as a base case for simulating options for GHG reductions in the cement industry. The modified process can reduce coal consumption and pipeline corrosion, and increase the efficiency of waste heat recovery and the calcination rate; these procedures require low investment and operating cost. [ABSTRACT FROM AUTHOR]

Graphene-titanium nanotube composites with different ratios of graphite oxide were prepared via the hydrothermal method using ascorbic acid as a reducing agent. Properties of materials were characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy, high resolution transmission electron microscopy and UV–vis diffuse reflectance spectroscopy. The average diameter of the titanium dioxide nanotubes was about 8 nm. The photoresponse of nanocomposites have been extended to visible-light regions. In addition, graphene-titanium nanotube composites showed higher photocatalytic degradation efficiency for reactive black 5 (RBK5) than pure titanium dioxide and the 15%graphene-titanium nanotube composites catalysts possessed the best photocatalytic activity. The degradation efficiency for RBK5 dyes increased with increased dosage of graphite oxide from 3%-15% and decreased with increasing initial RBK5 concentration. This paper not only reports the fabrication of highly active photocatalysts but also provides insight into the photocatalytic mechanism of graphene-titanium nanotube composites. [ABSTRACT FROM AUTHOR]

As it is the most important of the greenhouse gases, the utilization and reduction of carbon dioxide have attracted a great attention. As compared to the technological demands for carbon capture and storage (CCS), carbon dioxide reduction is a safe and effective way to convert carbon dioxide to fuel. In this research, two different catalysts, graphene–titania and zeolite–titania, are used to achieve the carbon dioxide reduction. The characteristics of these materials are analyzed by Brunnauer–Emmett–Teller, X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet–visible, scanning electron microscope and transmission electron microscopy. Because of the different features of the catalysts, various products can be generated through different pathways. Formic acid and methanol are the final products when graphene is used as the catalyst, but only methanol can be generated when zeolite–titania is used as the catalyst. The reaction mechanisms and pathways are discussed. [ABSTRACT FROM AUTHOR]

Acetaminophen is commonly used as an antipyretic or analgesics agent and poses threat to human health. In this research, TiO 2 and graphite oxide were used as precursors of titanium dioxide nanotubes and graphene respectively. Titanium dioxide nanotube and graphene (GR-TNT) nanocomposites were synthesized through a hydrothermal method. FT-IR, UV-Vis, XRD, and TGA were used to characterize the catalysts. The acetaminophen degradation rate can reach up to 96% under UV light irradiation for 3 h and with the 5% GR-TNT dosage of 0.1 g L −1 . Further experiments were done to probe the mechanism of the photocatalytic reaction catalyzed by the GR-TNT composite. EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to detect the main active oxidative species in the system. The results showed that the holes are the main oxidation species in the photocatalytic process. This study provides a new prospect for acetaminophen degradation by using high efficiency catalysts. [ABSTRACT FROM AUTHOR]

A novel photocatalyst of graphene–titania dioxide nanotube (GN–TNT) composites was prepared using a simple hydrothermal reaction with ascorbic acid as a reducing agent. High resolution transmission electron microscope (HR-TEM), fourier transform infrared spectrometer (FT-IR), thermo gravimetric analyzer (TGA) and N 2 adsorption/desorption analyzer (BET) methods were used to assess the morphologies and structures of as-synthesized materials. HR-TEM analysis further confirmed the presences of graphene and titanium (TiO 2 ) nanotubes in the nanocomposite photocatalyst. The results exhibited that photocatalytic performance of a GN–TNT photocatalyst significantly improved under visible light. In addition, the existence of a competitive effect between As 3+ and reactive black 5 (RBK5) molecules in the mixed solution was found. The photocatalytic process is also discussed in this paper. [ABSTRACT FROM AUTHOR]

Highlights: [•] Disclose new decolorized mediators to dye removal and bioelectricity generation. [•] Unveil mediating characteristics of bicyclic aromatics 1A2N, 4A1N to MFCs. [•] Suggest models of mediator-assisted MFCs for wastewater decolorization. [ABSTRACT FROM AUTHOR]

Mesoporous MCM-41 was synthesized using cetyltrimethyl ammonium bromide (CTAB) as a cationic surfactant and spent quartz sand as the silica source. Modification of the mesoporous structure to create an absorbent was then completed using 3-aminopropyltrimethoxysilane. Amine-Quartz-MCM (The A-Q-MCM) adsorbents were then characterized by N2adsorption/desorption, elemental analysis (EA), X-ray fluorescence (XRF), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), as well as the carbon dioxide (CO2) adsorption/desorption performance. In this study, spent quartz sand was utilized to synthesize Quartz-MCM (Q-MCM) and the amine functionalized material, A-Q-MCM, which exhibited a higher uptake of CO2at room temperature compared with the nongrafted material. The results showed that Q-MCM is similar to MCM-41 synthesized using commercial methods. The surface area, pore volume, and pore diameter were found to be as high as 1028 m2/g, 0.907 cm3/g, and 3.04 nm, respectively. Under the condition of CO2concentration of 5000 ppm, retention time of 50 cc/min, and the dosage of 1 g/cm3, the mean adsorption capacity of CO2onto A-Q-MCM was about 89 mg/g, and the nitrogen content of A-Q-MCM was 2.74%. The adsorption equilibrium was modeled well using a Freundlich isotherm.Implications:In this study, spent quartz sand was utilized to synthesize Q-MCM. The amine functionalized material exhibited a higher uptake of CO2 at room temperature compared with the nongrafted material. The results showed that Q-MCM is similar to MCM-41 synthesized using commercial methods. The adsorption equilibrium was modeled well using a Freundlich isotherm. [ABSTRACT FROM AUTHOR]

This study was the first used to explore the characteristics of prepared phosphorene materials as a promising As(III) treatment. Investigations on monolayer and few-layer black phosphorous, which is transformed to “phosphorene” have grown in number in the recent years. Similar to graphene, single-layer phosphorene is flexible and can be mechanically exfoliated. In this study, phosphorene catalysts were prepared by exfoliation method. Moreover, four levels of arsenic concentration, namely, 0.5, 1, 2, and 4 ppm, were tested. The morphology and elastic strain of the composites were analyzed by transmission electron microscopy. When graphene and phosphorene materials are compared, the most appropriate adsorption rate for As(III) was achieved at 0.0329 min −1 . The sorption capacity were 4.67 mg g −1 for As(III) at pH 7. [ABSTRACT FROM AUTHOR]