The simultaneous detection of multiple heavy metal ions in solution is an important yet highly challenging problem. In this work, a metal-free g-C3N4/carbon black (CB) composite electrode was ...synthesized by a one-step thermal polycondensation method and characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and ultraviolet visible light spectroscopy. In addition, the photoelectrochemical response of the g-C3N4/CB nanocomposite to Cd2+, Pb2+ and Hg2+ both separately and as a mixture of the three analytes was investigated by differential pulse anodic stripping voltammetry. The g-C3N4/CB electrode demonstrated an excellent sensing performance to Cd2+, Pb2+ and Hg2+ in the range of 0–700 nM, 0–300 nM and 0–500 nM, respectively, with limits of detection (LOD) of Cd2+, Pb2+, and Hg2+ of 2.1, 0.26 and 0.22 nM, respectively. The LOD of the combined solution of the three analytes was slightly higher at 3.3 nM. Additionally, the metal-free g-C3N4/CB photoelectrochemical sensor exhibited excellent electrochemical stability and electrode reproducibility. Finally, g-C3N4/CB sensor also showed satisfactory results in the detection of trace analyte ions in real environmental systems. This work provides a novel and promising approach in the simultaneous detection of multiple heavy metal ions in solution for practical applications.
Display omitted
•A new metal-free photo-responsive g-C3N4/CB electrochemical sensor is prepared.•It shows high sensitivity for simultaneous detection of multiple heavy metal ions.•The sensor displays excellent stability and reproducibility for metal ions detection.•The sensor detects trace analyte ions in real samples with satisfactory results.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•The combined effect of LWs and CB on SDSSS was evaluated.•The combination of LWs and CB enhanced thermal efficiency by 110.5% compared with TSS.•The productivity of SDSSS integrated with LWs and CB ...was improved by 80.57%.•Fractional exergy for convection and evaporation at different modifications was investigated.•The freshwater with minimum cost was achieved by the new combination of LWs and CB.
This work aims to improve the thermal and economic analysis of stepped double slope solar still (SDSSS) that integrated with linen wicks (LWs) and carbon black nanoparticles (CBNs). The LWs and CBNs were used to increase the evaporation surface area and enhance heat transfer of basin saline water. The SDSSS with LWs and LWs with CBNs were evaluated, and compared with traditional solar still (TSS). The energy and exergy for convection and evaporation and exergy efficiency for different modifications were analyzed, and its costs were discussed. Results indicated that adding LWs and CBNs to SDSSS increased the freshwater productivity and energy efficiency by 80.57 and 110.5%, respectively, compared to TSS. The SDSSS fractional exergy of evaporation was the highest in the case of integrating LWs and CBNs with the solar still due to the high basin water temperature. This modification caused the highest exergy efficiency for SDSSS because of enhanced photo-thermal properties of CBNs, and heat storage characteristic of LWs. Economic analysis indicated that the total costs per liter of produced freshwater for SDSSS without any modifications, SDSSS with LWs, SDSSS with CBNs, and SDSSS with LWs and CBNs were lower than TSS by 13.73, 19.91, 23.83, and 47.22%, respectively.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Coal-derived carbon black is the main composition of PM2.5, used in the rubber industry and energy storage fields. The formation and structure control of carbon black have attracted significant ...attention. Alkali metals have influence on the dynamic formation of coal-derived carbon black. To analyze the mechanism of Na in the formation of carbon black, a high-temperature drop tube furnace was used to analysis of carbon black from the pyrolysis of acid-washed coal and Na-containing coal at 1250 °C. DFT was applied to simulate the stepwise inhibitory effect of Na on the polymerization of PAHs into carbon black. The results show that Na promotes the oxidative cracking of large PAHs into small PAHs during the formation of coal-derived carbon black (reaction energy barrier is reduced by 17.7%), and inhibits the condensation of small PAHs molecules to form carbon black molecules (reaction energy barrier is increased by 74.7%), which causes the length of carbon black is shortened by 14.3%, and its curvature is increased by 1.7%. Na could change the spatial structure of formed carbon black-graphite crystallites, which increases the spacing of carbon black by approximately 6.2% to 16.3%. Na enhances the electrochemical performance of carbon black by 2 to 3 times.
Display omitted
•Experimental and DFT study of the catalytic effect of Na on carbon black.•Na promotes oxidation of PAHs and fracture of carbon black crystallites.•Na inhibits the polymerization of PAHs into carbon black particles.•Na changes carbon black structure, increasing the spacing by 6.2% ~ 16.3%.•The electrochemical performance of carbon black is enhanced 2–3 times by Na.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•The CB trapped into the CBp was recovered.•HCl concentration was the main parameter controlling the demineralization.•dCBp was used in SBR compounding.•Some dCBp properties were comparable to those ...of commercial CB N550.•Mechanical properties of the SBR/dCBp did not show a significant detriment.
Pyrolysis offers the possibility to convert waste tires into liquid and gaseous fractions as well as a carbon-rich solid (CBp), which contains the original carbon black (CB) and the inorganic compounds used in tire manufacture. Whilst both liquid and gaseous fractions can be valorized without further processing, there is a general consensus that CBp needs to be improved before it can be considered a commercial product, seriously penalizing the pyrolysis process profitability. In this work, the CBp produced in a continuous pyrolysis process was demineralized (chemical leaching) with the aim of recovering the CB trapped into the CBp and thus, producing a standardized CB product for commercial purposes. The demineralization process was conducted by using cheap and common reagents (HCl and NaOH). In this sense, the acid treatment removed most of the mineral matter contained in the CBp and concentration was the main parameter controlling the demineralization process. An ash content of 4.9 wt% was obtained by using 60 min of soaking time, 60 °C of temperature, 10 mL/g of reagent/CBp ratio and HCl 4 M. The demineralized CBp (dCBp) showed a carbon content of 92.9 wt%, while the FRX analysis indicated that SiO2 is the major component into the ash. The BET surface area was 76.3 m2/g, and textural characterizations (SEM/EDX and TEM) revealed that dCBp is composed by primary particles lower than 100 nm. Although dCBp showed a low structure, the surface chemistry was rich in surface acidic groups. Finally, dCBp was used in Styrene Butadiene Rubber (SBR) compounding, probing its technical feasibility as substitute of commercial CB N550.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Solar steam generation (SSG) offers a sustainable approach to fresh water production. Herein, a novel dual-functional natural rubber/carbon black composite foam evaporator is presented for a ...cost-efficient SSG system that both produces fresh water and eliminates heavy metals present in the water. The composite foam is produced using the Dunlop process, and in its optimized form, it absorbed >96 % of sunlight. The foam evaporator exhibited a thermal conductivity of 0.052 W/m⋅K, a water evaporation rate of 1.40 kg/m2/h, converted 83.38 % of light to heat under 1 sun irradiation, and showed outstanding stability. The technology required to produce this composite foam is already available to make large-scale production feasible, while the natural raw materials are abundant. On the basis of its performance qualities, the rubber foam composite appears to be an excellent candidate for application as a viable solar absorber for SSG to produce fresh, clean water for commercial purposes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Display omitted
•PDA/CB composite non-woven PP fabric was prepared for solar energy harvesting.•Hierarchical structure and synergetic effects of CB/PDA contributed to high light absorbance.•The ...evaporation rate of 1.68 kg m-2h−1 with a solar steam efficiency of 91.5% was achieved.•The solar evaporator demonstrated superior salt resistance and ability to purify seawater and various wastewaters with high efficiency.
The utilization of solar energy for steam generation is a highly efficient and sustainable technology for seawater desalination to solve the long-standing water crisis. Carbon-based materials have shown promising thermal-heat conversion efficiency due to their broadband solar absorption. Herein, carbon black (CB) was combined with polydopamine (PDA) to develop a high-performance, low-cost, and scalable PDA/CB@PP composite non-woven fabric was fabricated by dip-coating of CB and in situ polymerization of PDA. The hierarchical structure constructed on the fiber surface and the synergetic effects of CB and PDA contributed to the high light absorbance (>95%), superhydrophilicity, and high energy conversion efficiency. The one-way fluidic PDA/CB@PP photothermal based solar steam evaporator demonstrated a high evaporation rate of 1.68 kg m-2h−1 with a solar steam efficiency of 91.5%. Moreover, the PDA/CB@PP fabric shows remarkable salt resistance when purifying seawater because of the water channel preserved by the hydrophilic porous structure of the fabric which could provide sustained water supply. Besides, the PDA/CB@PP fabric possesses excellent purification capability to wastewaters contaminated by heavy-metal and chemical dyes. This study provides insights into the design and development of low-cost, scalable, highly stable, and efficient solar steam generators for seawater desalination and wastewater purification.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Accurate representations of the 3D structure within a lithium‐ion battery are key to understanding performance limitations. However, obtaining exact reconstructions of electrodes, where the active ...particles, the carbon black and polymeric binder domain, and the pore space are visualized is challenging. Here, it is shown that multimodal imaging can be used to overcome this challenge. High‐resolution ptychographic X‐ray computed tomography are combined with lower resolution but higher contrast transmission X‐ray tomographic microscopy to obtain 3D reconstructions of pristine and cycled graphite‐silicon composite electrodes. This cross‐correlation enables quantitative analysis of the surface of active particles, including the heterogeneity of carbon‐black and binder domain and solid‐electrolyte interphase coverage. Capturing the active particles as well as the carbon black‐binder domain allows using these segmented structures for electrochemical simulations to highlight the influence of the particle embedding on local state of charge heterogeneities.
This work shows how data from imaging techniques with different resolutions and contrasts (e.g., higher‐resolution, lower‐contrast ptychographic X‐ray computed tomography and higher‐contrast, lower resolution transmission X‐ray tomographic microscopy) can be combined to enable semantic segmentation of images having low contrast and small features such as those found in high‐energy, lithium‐ion battery electrodes or other heterogenous porous media.
Full text
Available for:
FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This paper presents a comprehensive assessment of historical (1990–2010) global anthropogenic particulate matter (PM) emissions including the consistent and harmonized calculation of mass-based size ...distribution (PM1, PM2. 5, PM10), as well as primary carbonaceous aerosols including black carbon (BC) and organic carbon (OC). The estimates were developed with the integrated assessment model GAINS, where source- and region-specific technology characteristics are explicitly included. This assessment includes a number of previously unaccounted or often misallocated emission sources, i.e. kerosene lamps, gas flaring, diesel generators, refuse burning; some of them were reported in the past for selected regions or in the context of a particular pollutant or sector but not included as part of a total estimate. Spatially, emissions were calculated for 172 source regions (as well as international shipping), presented for 25 global regions, and allocated to 0.5° × 0.5° longitude–latitude grids. No independent estimates of emissions from forest fires and savannah burning are provided and neither windblown dust nor unpaved roads emissions are included. We estimate that global emissions of PM have not changed significantly between 1990 and 2010, showing a strong decoupling from the global increase in energy consumption and, consequently, CO2 emissions, but there are significantly different regional trends, with a particularly strong increase in East Asia and Africa and a strong decline in Europe, North America, and the Pacific region. This in turn resulted in important changes in the spatial pattern of PM burden, e.g. European, North American, and Pacific contributions to global emissions dropped from nearly 30 % in 1990 to well below 15 % in 2010, while Asia's contribution grew from just over 50 % to nearly two-thirds of the global total in 2010. For all PM species considered, Asian sources represented over 60 % of the global anthropogenic total, and residential combustion was the most important sector, contributing about 60 % for BC and OC, 45 % for PM2. 5, and less than 40 % for PM10, where large combustion sources and industrial processes are equally important. Global anthropogenic emissions of BC were estimated at about 6.6 and 7.2 Tg in 2000 and 2010, respectively, and represent about 15 % of PM2. 5 but for some sources reach nearly 50 %, i.e. for the transport sector. Our global BC numbers are higher than previously published owing primarily to the inclusion of new sources. This PM estimate fills the gap in emission data and emission source characterization required in air quality and climate modelling studies and health impact assessments at a regional and global level, as it includes both carbonaceous and non-carbonaceous constituents of primary particulate matter emissions. The developed emission dataset has been used in several regional and global atmospheric transport and climate model simulations within the ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) project and beyond, serves better parameterization of the global integrated assessment models with respect to representation of black carbon and organic carbon emissions, and built a basis for recently published global particulate number estimates.
Schematic illustration of the developed analytical procedure. I) Synthesis of the US-MagMIP; II) (A) Rebinding process between BPA and US-MagMIP (B) separation of US-MagMIP from the solution and ...throw the supernatant (C) Elution of BPA using phosphate buffer containing 20% of methanol (D) Drop-casting of 60 μL of the residual concentration of BPA on the surface of AuNPs/CBNPs/SPCE; III) Electrochemical detection of BPA using the developed sensor.
Display omitted
•A simple and rapid method for monitoring BPA in water samples was developed.•The US-magMIP combined with SPCE modified CBNPs and AuNPs was used.•The electrochemical sensing approach exhibits a highly selective and sensitive detection towards BPA.
Sample preparation is considered as one of the most interesting applications of magnetic molecularly imprinted polymer (MagMIP) used as adsorbents for various compounds prior to their determination using the developed analytical techniques. In this context, we present in this paper a developed Ultrasound-assisted magnetic molecularly imprinted polymer (US-MagMIP) combined to an electrochemical sensor modified with a nanocomposite of carbon black nanoparticles (CBNPs), and Gold nanoparticles (AuNPs) for highly selective and sensitive detection of Bisphenol A (BPA). The electrochemical characterization of the developed sensor was investigated by electrochemical impedance spectroscopy and cyclic voltammetry. Various parameters were optimized such as the effect of voltammetric mode, the effect of pH, the amount of US-MagMIP and the rebinding time. The electrochemical sensor exhibits a high sensitivity for BPA with a LOD of 8.8 nM with a wide linear range from 0.07 μM to 10 μM. Moreover, this sensor provides a high selectivity towards various likely interferents by combination with US-MagMIP prior to analysis. The developed analytical approach was applied successfully for determination of BPA in Tap and mineral water samples.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Carbon black (CB) is a carbon material produced by either thermal decomposition or incomplete combustion of hydrocarbons under controlled conditions. With industrial applications as an ...elastomer-reinforcing agent, a conductive filler, a coating agent, a dyeing agent and adsorbent for heavy metal removal, CB is listed as one of the top 50 industrial chemicals globally. The current feedstocks utilised in CB production are fossil fuel-based resources hence susceptible to volatile oil prices in addition to the associated high CO2 emission. There has been a growing interest in using feedstocks from renewable sources and recycled wastes to produce CB. Guided by the principles of cleaner production, this paper reviews the current state of CB production using renewable and recycled waste resources with a particular feedstock of interest being spent tyre pyrolysis oil. The utilisation of spent tyre pyrolysis oil as a feedstock offers a cleaner production route to CB manufacturing with improved environmental performance and reduced costs. The formation mechanisms and key governing factors for suitable CB feedstock selection are reviewed. Various resources for CB production are summarised and discussed. The chemical compositions and physical properties of spent tyre pyrolysis oil from various processes are analysed and compared with other feedstocks, providing a basis for evaluating the possibility of using spent tyre pyrolysis oil for CB production.
Display omitted
•Carbon black production from renewable and wastes resources systematically reviewed.•Aromaticity, C/H and sulphur contents are key factors in feedstock selection.•Spent tyre pyrolysis oil is a feasible feedstock for premium carbon black production.•Yield and structural properties of CB from pyrolysis oil need to be examined.•Conversion of spent tyre oil to CB follows the cleaner production principles.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
