C | Special Issue : Carbons for Health and Environmental Protection

Research

Jump to: Review

12 pages, 1240 KiB

Open AccessArticle

Divergence in Antiviral Activities of Carbon Dots versus Nano-Carbon/Organic Hybrids and Implications

by Cristian E. Rodriguez, Audrey F. Adcock, Buta Singh, Subhadra Yerra, Yongan Tang, Ya-Ping Sun and Liju Yang

C 2023, 9(3), 79; https://doi.org/10.3390/c9030079 - 20 Aug 2023

Cited by 1 | Viewed by 1763

Abstract

Carbon dots (CDots) are generally defined as small carbon nanoparticles (CNPs) with effective surface passivation, for which the classical synthesis is the functionalization of pre-existing CNPs with organic molecules. However, “dot” samples produced by “one-pot” thermal carbonization of organic precursors are also popular [...] Read more.

Carbon dots (CDots) are generally defined as small carbon nanoparticles (CNPs) with effective surface passivation, for which the classical synthesis is the functionalization of pre-existing CNPs with organic molecules. However, “dot” samples produced by “one-pot” thermal carbonization of organic precursors are also popular in the literature. These carbonization-produced samples may contain nano-carbon domains embedded in organic matters from the precursors that survived the thermal processing, which may be considered and denoted as “nano-carbon/organic hybrids”. Recent experimental evidence indicated that the two different kinds of dot samples are largely divergent in their photo-induced antibacterial functions. In this work, three representative carbonization-produced samples from the precursor of citric acid–oligomeric polyethylenimine mixture with processing conditions of 200 °C for 3 h (CS200), 330 °C for 6 h (CS330), and microwave heating (CS_MT) were compared with the classically synthesized CDots on their photo-induced antiviral activities. The results suggest major divergences in the activities between the different samples. Interestingly, CS_MT also exhibited significant differences between antibacterial and antiviral activities. The mechanistic origins of the divergences were explored, with the results of different antimicrobial activities among the hybrid samples rationalized in terms of the degree of carbonization in the sample production and the different sample structural and morphological characteristics. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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11 pages, 3656 KiB

Open AccessArticle

Diamond as Insulation for Conductive Diamond—A Spotted Pattern Design for Miniaturized Disinfection Devices

by Manuel Zulla, Vera Vierheilig, Maximilian Koch, Andreas Burkovski, Matthias Karl and Stefan Rosiwal

C 2023, 9(3), 78; https://doi.org/10.3390/c9030078 - 18 Aug 2023

Viewed by 1597

Abstract

Boron-doped diamond (BDD) electrodes are well known for the in situ production of strong oxidants. These antimicrobial agents are produced directly from water without the need of storage or stabilization. An in situ production of reactive oxygen species (ROS) used as antimicrobial agents [...] Read more.

Boron-doped diamond (BDD) electrodes are well known for the in situ production of strong oxidants. These antimicrobial agents are produced directly from water without the need of storage or stabilization. An in situ production of reactive oxygen species (ROS) used as antimicrobial agents has also been used in recently developed medical applications. Although BDD electrodes also produce ROS during water electrolysis, only a few medical applications have appeared in the literature to date. This is probably due to the difficulties in the miniaturization of BDD electrodes, while maintaining a stable and efficient electrolytic process in order to obtain a clinical applicability. In this attempt, a cannula-based electrode design was achieved by insulating the anodic diamond layer from a cathodic cannula, using a second layer of non-conducting diamond. The undoped diamond (UDD) layer was successfully grown in a spotted pattern, resulting in a perfectly insulated yet still functional BDD layer, which can operate as a miniaturized flow reactor for medical applications. The spotted pattern was achieved by introducing a partial copper layer on top of the BDD layer, which was subsequently removed after growing the undoped diamond layer via etching. The initial analytical observations showed promising results for further chemical and microbial investigations. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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21 pages, 2874 KiB

Open AccessArticle

Adsorption of Cobalt and Strontium Ions on Plant-Derived Activated Carbons: The Suggested Mechanisms

by Irina Ceban (Ginsari), Tudor Lupascu, Sergey Mikhalovsky and Raisa Nastas

C 2023, 9(3), 71; https://doi.org/10.3390/c9030071 - 21 Jul 2023

Cited by 2 | Viewed by 2079

Abstract

In this study, activated carbons derived from walnut shells (CA-N) and apple wood (CA-M) were used as adsorbents to remove cobalt(II) and strontium(II) ions from aqueous solutions. The novel materials were obtained using nitric acid (CA-Mox) and nitric acid/urea mixture (CA-Mox-u, CA-Nox-u) as [...] Read more.

In this study, activated carbons derived from walnut shells (CA-N) and apple wood (CA-M) were used as adsorbents to remove cobalt(II) and strontium(II) ions from aqueous solutions. The novel materials were obtained using nitric acid (CA-Mox) and nitric acid/urea mixture (CA-Mox-u, CA-Nox-u) as oxidizing agents. The physical–chemical characteristics of activated carbons were determined from nitrogen sorption isotherms, SEM-EDX, FTIR, pH metric titrations, the Boehm titration method and elemental analysis. The results of batch experiments indicate that maximum adsorption can be achieved in broad pH ranges: 4–8 for Co(II) and 4–10 for Sr(II). The maximum adsorption capacities of Co(II) and Sr(II) on oxidized activated carbons at pH = 4 are: CA-Mox, 0.085 and 0.076 mmol/g; CA-Mox-u, 0.056 and 0.041 mmol/g; and CA-Nox-u, 0.041 and 0.034 mmol/g, respectively. The mathematical models (pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models, and Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin–Pyzhev isotherm models) were used to explain the adsorption kinetics, to study the adsorption mechanism and predict maximum adsorption capacity of the adsorbents. The adsorption mechanisms of toxic metal ions on activated carbons were proposed. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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16 pages, 6377 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Effect of Carbon Nanoparticles on the Porous Texture of ι-Carrageenan-Based N-Doped Nanostructured Porous Carbons and Implications for Gas Phase Applications

by Samantha K. Samaniego Andrade, Alfréd Menyhárd, Szilvia Klébert, Miklós Mohai, Balázs Nagy and Krisztina László

C 2023, 9(3), 68; https://doi.org/10.3390/c9030068 - 12 Jul 2023

Cited by 2 | Viewed by 1860

Abstract

S and N double-doped high surface area biomass-derived carbons were obtained from marine biomass-derived ι-carrageenan. Adding carbon nanoparticles (CNPs), namely graphene oxide (GO) or carbon nanotubes (CNTs), in the early stage of the synthesis leads to a modified porous texture and surface chemistry. [...] Read more.

S and N double-doped high surface area biomass-derived carbons were obtained from marine biomass-derived ι-carrageenan. Adding carbon nanoparticles (CNPs), namely graphene oxide (GO) or carbon nanotubes (CNTs), in the early stage of the synthesis leads to a modified porous texture and surface chemistry. The porous textures were characterized by N₂ (−196.15 °C) and CO₂ (0 °C) isotherms. The best GO- and CNT-added carbons had an apparent surface area of 1780 m²/g and 1170 m²/g, respectively, compared to 1070 m²/g for the CNP-free matrix. Analysis of the Raman spectra revealed that CNT was more efficient in introducing new defects than GO. Based on XPS, the carbon samples contain 2–4.5 at% nitrogen and 1.1 at% sulfur. The Dubinin–Radushkevich (DR) and Henry models were used to assess the strength of the interactions between various gases and the surface. The N₂/H₂ and CO₂/CH₄ selectivities were estimated with ideal adsorbed solution theory (IAST). While the CNPs, particularly GO, had a remarkable influence on the porous texture and affected the surface chemistry, their influence on the separation selectivity of these gases was more modest. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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17 pages, 4111 KiB

Open AccessArticle

Application of Lolium multiflorum as an Efficient Raw Material in the Production of Adsorbent for Removal of Methylene Blue

by Elenara Oliveira da Silva, Alaor Valério Filho, Emanuelle Butato de Araujo, Taís Douglas Andrade, Maele Costa dos Santos, Ricardo Zottis, Gabriela Silveira da Rosa and André Ricardo Felkl de Almeida

C 2023, 9(2), 44; https://doi.org/10.3390/c9020044 - 26 Apr 2023

Cited by 5 | Viewed by 1810

Abstract

In this study, ryegrass straw agricultural residue (Lolium multiflorum L.) was employed as an adsorbent material to remove methylene blue (MB) dye from aqueous solutions. Four adsorbents were produced using phosphoric acid and pyrolysis as activating agents. The samples were analyzed with [...] Read more.

In this study, ryegrass straw agricultural residue (Lolium multiflorum L.) was employed as an adsorbent material to remove methylene blue (MB) dye from aqueous solutions. Four adsorbents were produced using phosphoric acid and pyrolysis as activating agents. The samples were analyzed with TGA, FTIR, SEM, and XRD techniques. A rapid adsorption of the MB was obtained with the ryegrass treated with 40% H₃PO₄, reaching equilibrium in 2 min. Moreover, a maximum adsorption capacity of 80.79 mg g⁻¹ and a removal efficiency of 99% were achieved. The results demonstrate a good performance of adsorbents from ryegrass for removing dye contaminants, such as methylene blue, from the aqueous solutions. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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13 pages, 3170 KiB

Open AccessArticle

A Composite Magnetosensitive Sorbent Based on the Expanded Graphite for the Clean-Up of Oil Spills: Synthesis and Structural Properties

by Vadim M. Kadoshnikov, Tetyana I. Melnychenko, Oksana M. Arkhipenko, Danylo H. Tutskyi, Volodymyr O. Komarov, Leonid A. Bulavin and Yuriy L. Zabulonov

C 2023, 9(2), 39; https://doi.org/10.3390/c9020039 - 12 Apr 2023

Cited by 3 | Viewed by 2105

Abstract

Oil spills necessitate the development of effective methods for preventing their damaging effects on the environment. A number of physical, chemical, thermal, and biological methods are used to combat oil spills. Among them, sorption is considered to be efficient in removing thin oil [...] Read more.

Oil spills necessitate the development of effective methods for preventing their damaging effects on the environment. A number of physical, chemical, thermal, and biological methods are used to combat oil spills. Among them, sorption is considered to be efficient in removing thin oil films from water surfaces. Currently, there is an urgent need for simple methods of obtaining oil sorbents that include a magnetosensitive component to optimize the process of removing oil from the water surface. The purpose of the work is to obtain and research oil sorbents resistant to destruction, with increased bulk density and complex magnetosensitivity, based on thermally expanded graphite (TEG) with the inclusion of micro- and nano-particles of iron and its oxides. The structure and composition of the new composite material was characterized using scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffractometry, thermogravimetric analysis, and laser diffraction particle sizing. The composite sorbent comprised TEG with the inclusion of iron-containing magnetosensitive particles. Metal-carbon nanoparticles (MCN) were used as the magnetosensitive component; they had a magnetosensitive iron core covered with a carbon shell. We used two methods of synthesis, namely (i) mechanical mixing of the TEG flakes and MCN particles, and (ii) applying a thermal shock (microwave processing) to the mixture of graphite intercalated with sulphuric acid and micro- and nanoparticles of iron and iron oxides. In the first case, MCN particles were fixed on the faces, edges, and other surface defects of the TEG flakes due to intermolecular forces, coordinate bonds, and electrostatic interaction. The strong adhesion of magnetosensitive iron/iron oxide and TEG particles in the second case was due to the mutual dissolution of iron and carbon components during the thermal shock, which formed an interfacial layer in which iron carbide is present. The presence of magnetosensitive components in the structure of the proposed oil sorbents allows the use of magnetic separation for the localization and removal of oil spills, increases the density of sorbents, and, accordingly, leads to a decrease in windage while retaining the advantageous properties of thermally expanded graphite. According to the results of laboratory studies, the efficiency of removing oil from the water surface is not lower than 95–96%. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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17 pages, 4323 KiB

Open AccessArticle

Doping of Graphene Nanostructure with Iron, Nickel and Zinc as Selective Detector for the Toxic Gas Removal: A Density Functional Theory Study

by Fatemeh Mollaamin and Majid Monajjemi

C 2023, 9(1), 20; https://doi.org/10.3390/c9010020 - 9 Feb 2023

Cited by 21 | Viewed by 2912

Abstract

In this research, the ability of transition metals (TM)-doped graphene nanosheets to adsorb the toxic gas CO has been investigated. The Langmuir adsorption model was used, with a three-layered ONIOM, using the CAM-B3LYP functional accompanying the LANL2DZ and 6-31+G (d,p) basis sets, and [...] Read more.

In this research, the ability of transition metals (TM)-doped graphene nanosheets to adsorb the toxic gas CO has been investigated. The Langmuir adsorption model was used, with a three-layered ONIOM, using the CAM-B3LYP functional accompanying the LANL2DZ and 6-31+G (d,p) basis sets, and using the Gaussian 16 revision C.01 program, on the complexes of CO adsorbed on (Fe, Ni, Zn)-doped graphene nanosheets. The order of the changes of charge density for the Langmuir adsorption of CO on Fe-doped, Ni-doped, and Zn-doped graphene nanosheets has been investigated. This shows the greatest change of charge density for the Ni-doped graphene nanosheet. However, based on NMR spectroscopy, sharp peaks around the Ni-doped area on the surface of the graphene nanosheet have been observed. In addition, the Ni-doped graphene nanosheet has a large effect on the bond orbitals of C-Ni in the adsorption of CO, having the maximum occupancy. The values of

Δ G_{a d s}^{o}

, calculated through IR, showed that

Δ G_{a d s, CO \to Fe - doped GR}^{o}

has the highest value, because of a charge density transfer from the oxygen atom in carbon monoxide to the Fe-doped graphene nanosheet. The frontier molecular orbitals, HOMO and LUMO, and the band energy gap accompanying some chemical reactivity parameters, have revealed the attributes of the molecular electrical transport of (Fe, Ni, Zn)-doped graphene nanosheets for the adsorption of CO. As a result, since a CO molecule interacts simultaneously with a Fe, Ni, or Zn atom and the C-C nanosheet, at first it might be separated, as in this state a CO atom constructs a physical bond with the Fe, Ni, or Zn atom, and then the other could be adsorbed chemically on the C-C nanosheet surface. Finally, our results have shown that a considerable amount of charge transfer occurs between CO molecules and TM-doped graphene nanosheets after adsorption, which suggests that TM-doped graphene is more sensitive and selective to the adsorption of CO than a pristine graphene surface. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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10 pages, 1621 KiB

Open AccessCommunication

A Novel Approach to Water Softening Based on Graphene Oxide-Activated Open Cell Foams

by Riccardo Balzarotti, Alessandro Migliavacca, Andrea Basso Peressut, Alessandro Mansutti and Saverio Latorrata

C 2023, 9(1), 6; https://doi.org/10.3390/c9010006 - 7 Jan 2023

Viewed by 2108

Abstract

This work focuses on exploring a new configuration for the reduction of water hardness based on the surface modification of polyurethane (PU) open cell foams by the deposition of thin graphene oxide (GO) washcoat layers. GO was deposited by the dip–squeeze coating procedure [...] Read more.

This work focuses on exploring a new configuration for the reduction of water hardness based on the surface modification of polyurethane (PU) open cell foams by the deposition of thin graphene oxide (GO) washcoat layers. GO was deposited by the dip–squeeze coating procedure and consolidated by thermal treatment. The final washcoat load was controlled by performing consecutive depositions, after three of which, a GO inventory up to 27 wt% was obtained onto PU foams of 60 pores per inch (PPI). The GO-coated PU foams were assembled into a filter, and the performance of the system was tested by continuously feeding water with hardness in the 190–270 mg_Ca2+,eq·L⁻¹ range. Remarkable results were demonstrated in terms of total adsorbing capacity, which was evaluated by measuring the outlet total hardness by titration and exhibited values up to 63 mg_Ca2+,eq·g_GO⁻¹ at a specific filtered water volume of 650 mL_H2O·g_GO⁻¹, outperforming the actual state-of-the-art adsorbing capacity of similar GO-based materials. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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15 pages, 2834 KiB

Open AccessArticle

Conversion of Coal-Biomass into Diesel by Using Aspen Plus

by Bilal Bashir, Muhammad Amin, Anaiz Gul Fareed and Zia Ur Rahman Farooqi

C 2022, 8(4), 63; https://doi.org/10.3390/c8040063 - 10 Nov 2022

Cited by 1 | Viewed by 3024

Abstract

Taking the importance of Pakistan’s dire need for energy breakthrough, in this paper, we explore how the country’s vast estimated reserves of 175 billion tons of Thar coal is a useful source for the clean and efficient production of good quality liquid fuel. [...] Read more.

Taking the importance of Pakistan’s dire need for energy breakthrough, in this paper, we explore how the country’s vast estimated reserves of 175 billion tons of Thar coal is a useful source for the clean and efficient production of good quality liquid fuel. Coal to liquid (CTL) technology has gathered increasing attention among many countries with a sufficient volume of coal reserves, and this technology can also be implemented in Pakistan, which in result can also reduce harmful greenhouse gas (GHG) emissions in the environment. In this study, the Fischer Tropsch Synthesis (FT) liquefaction method was used, and the reactor design, chemical reactions, syngas ratio fraction, and Anderson-Schulz-Flory and Langmuir model were all obtained from the Aspen Plus simulation. The results showed that, at the optimum syngas flow rate of 9 Kg/s, the FT model produced diesel fuel at 0.00134 Kg/s. Per this calculation, the massive amount of Thar coal reserves can be transformed into 123.22 million barrels of diesel. The design of the reactor is very critical, and, in this study, it was prioritized to design a reactor that produces liquid fuel only of composition C₁₂+; during the production of liquid fuel, the quantity of methane is not high; and it can still be further reduced on optimized conditions. On the other hand, CO₂ gas, which is a sole contributor of GHG emissions, was also reduced by up to 98%. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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13 pages, 4167 KiB

Open AccessArticle

Effect of Absorption Time for the Preparation of Activated Carbon from Wasted Tree Leaves of Quercus alba and Investigating Life Cycle Assessment

by Muhammad Amin and Hamad Hussain Shah

C 2022, 8(4), 57; https://doi.org/10.3390/c8040057 - 28 Oct 2022

Cited by 12 | Viewed by 2192

Abstract

In this article, the effect of absorption time on the surface chemistry and pore structure of activated carbon (AC) from waste leaves of Quercus alba with the H₃PO₄ chemical activation method. XRD, SEM, EDX, BET, TGA, and FT-IR analyses of [...] Read more.

In this article, the effect of absorption time on the surface chemistry and pore structure of activated carbon (AC) from waste leaves of Quercus alba with the H₃PO₄ chemical activation method. XRD, SEM, EDX, BET, TGA, and FT-IR analyses of prepared AC were used to figure out the properties of the activated carbon. The results demonstrated that the 48 h absorption time of H₃PO₄ contributed to the highest surface area, 943.2 m²/g, among all the prepared activated carbon samples. As the absorption time of the phosphoric acid activating agent was increased, the surface area initially increased and then started to decrease. The further surface chemical characterization of activated carbon was determined by FT-IR spectroscopic method. Life cycle assessment methodology was employed in order to investigate the environmental impacts associated with the laboratory steps for activated carbon (AC) production. The LCA approach was implemented using OpenLCA 1.10.3 software, while ReCiPe Midpoint (H) was used for environmental impact assessment. The results of the LCA study showed that the impact categories related to toxicity were particularly affected by the utilization of electrical energy (≈90%). The power utilized during laboratory procedures was the main cause of environmental impacts, contributing an average of nearly 70% across all impact categories, with the maximum contribution to the impact category of freshwater ecotoxicity potential (≈97%) and the minimum contribution to land use potential (≈10%). Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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14 pages, 3975 KiB

Open AccessArticle

Structural Evolution of Polyimide-Derived Carbon during Phosphoric Acid Activation

by Alexander M. Puziy, Olga I. Poddubnaya, Barbara Gawdzik, Magdalena Sobiesiak and Myroslav Sprynskyy

C 2022, 8(3), 47; https://doi.org/10.3390/c8030047 - 19 Sep 2022

Cited by 8 | Viewed by 2480

Abstract

Carbon adsorbents were obtained by carbonization of polyimide polymer with and without the presence of phosphoric acid at temperatures in the range of 400–1000 °C. Carbons produced in the presence of phosphoric acid have been demonstrated to contain up to 13.2% phosphorus. The [...] Read more.

Carbon adsorbents were obtained by carbonization of polyimide polymer with and without the presence of phosphoric acid at temperatures in the range of 400–1000 °C. Carbons produced in the presence of phosphoric acid have been demonstrated to contain up to 13.2% phosphorus. The structure of phosphorus-containing compounds was investigated by XPS and ³¹P MAS NMR methods. Deconvolution of the P 2p peak with variable binding energy showed the presence of only phosphates/polyphosphates. However, a low value of the O/P ratio is an indirect indication of the possible presence of phosphonates. A ³¹P MAS NMR study revealed the existence of several kinds of phosphates as well as a minor quantity (1–9%) of phosphonates. All discovered phosphorus-containing compounds are acidic and therefore give carbon the ability to absorb metal cations. The study of copper ion adsorption demonstrated that phosphorus-containing carbon shows a significant adsorption capability even in extremely acidic conditions. At pH 3–6, phosphorus-containing carbon may completely remove copper from the aqueous solution. Phosphorus-containing carbon has a higher adsorption capacity for copper ions than ion exchange resins with carboxyl or sulfo groups. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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18 pages, 2459 KiB

Open AccessArticle

Effect of Porosity and Surface Chemistry on CO₂ and CH₄ Adsorption in S-Doped and S-/O-co-Doped Porous Carbons

by Snezana Reljic, Manuel Martinez-Escandell and Joaquin Silvestre-Albero

C 2022, 8(3), 41; https://doi.org/10.3390/c8030041 - 15 Aug 2022

Cited by 14 | Viewed by 3386

Abstract

The aim of this study was to determine the adsorption performance of a petroleum pitch-based activated carbon (PPAC1:3) before and after a post-treatment with H₂S. In the first step, a microporous activated carbon (PPAC1:3) with a highly developed porous structure was [...] Read more.

The aim of this study was to determine the adsorption performance of a petroleum pitch-based activated carbon (PPAC1:3) before and after a post-treatment with H₂S. In the first step, a microporous activated carbon (PPAC1:3) with a highly developed porous structure was produced through a chemical activation route with KOH. Afterward, the synthesized activated carbon was thermally treated yielding two different series of functionalized activated carbons: (i) a series of carbons were treated directly with H₂S at elevated temperatures (600 °C and 800 °C), and (ii) a series of carbons were generated by combining an oxidation treatment with plasma followed by H₂S treatment at elevated temperatures (600 °C and 800 °C). The chemical and structural characteristics of the S-doped and S-/O-co-doped porous carbons were investigated by means of different experimental techniques, such as XRD, RAMAN, FESEM, XPS, TPD, N₂, and CO₂ adsorption, and finally tested in CO₂ and CH₄ adsorption at atmospheric and high pressure. The functionalized porous carbons possessed specific surface areas of 2420–2690 m²/g, total pore volume of 1.05–1.18 cm³/g, and sulfur content up to 2.55 atom % (the sulfur content of the original carbon was 0.19%). After a careful analysis of the carbon dioxide and methane uptake at atmospheric (0.1 MPa) and high pressure (4 MPa), adsorption results confirm that the microporous structure is the main structural parameter defining the adsorption performance and, to a lower extent, the surface chemistry. Overall, a significant improvement in the total uptake can be appreciated after the H₂S treatment. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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Review

Jump to: Research

18 pages, 2047 KiB

Open AccessReview

Towards Understanding the Factors behind the Limited Integration of Multispecies Ecotoxicity Assessment in Environmental Risk Characterisation of Graphene-Family Materials—A Bibliometric Review

by Ildikó Fekete-Kertész, Krisztina László and Mónika Molnár

C 2023, 9(4), 90; https://doi.org/10.3390/c9040090 - 25 Sep 2023

Cited by 1 | Viewed by 1651

Abstract

Even though graphene-family materials (GFMs) hold great promise for various applications, there are still significant knowledge gaps in ecotoxicology and environmental risk assessment associated with their potential environmental impacts. Here, we provide a critical perspective on published ecotoxicity studies of GFMs based on [...] Read more.

Even though graphene-family materials (GFMs) hold great promise for various applications, there are still significant knowledge gaps in ecotoxicology and environmental risk assessment associated with their potential environmental impacts. Here, we provide a critical perspective on published ecotoxicity studies of GFMs based on meticulous bibliometric research. Based on the results of our review paper, in order to fill in the current critical knowledge gaps, the following issues are recommended for consideration: performing more studies on GFMs’ effects at environmentally relevant concentrations and more field and laboratory studies with marine and terrestrial organisms. It is also recommended to assess the ecotoxicity of GFMs in more environmentally relevant conditions, such as in trophic chain transfer studies and by multispecies exposure in micro- or mesocosms, as well as gaining insights into the interactive effects between GFMs and environmental pollutants. It was also revealed that despite their widespread detection in different environmental compartments the potential impacts of GFMs in complex test systems where hierarchical trophic organisation or trophic transfer studies are significantly under-represented. One of the main causes was identified as the difficulties in the physicochemical characterisation of GFMs in complex terrestrial test systems or aquatic micro- and mesocosm studies containing a sediment phase. The lack of tools for adequate characterisation of GFMs in these complex test systems may discourage researchers from conducting experiments under environmentally relevant test conditions. In the coming years, fundamental research about these complex test systems will continue to better understand the mechanism behind GFM toxicity affecting organisms in different environmental compartments and to ensure their safe and sustainable use in the future. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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21 pages, 759 KiB

Open AccessReview

Activated Carbon for Sepsis Prevention and Intervention: A Modern Way of Utilizing Old Therapies

by Elisaveta Snezhkova, Heinz Redl, Johannes Grillari and Marcin Osuchowski

C 2023, 9(3), 72; https://doi.org/10.3390/c9030072 - 25 Jul 2023

Cited by 1 | Viewed by 4863

Abstract

(1) Background: Uncontrolled inflammation often contributes to life-threatening sepsis sequela such as multi-organ dysfunction syndrome (MODS), and is accompanied by abnormal levels of pathological and damage-associated molecular patterns (PAMPs & DAMPs) in biological fluids. Activated carbon or charcoal (AC) of new generation with [...] Read more.

(1) Background: Uncontrolled inflammation often contributes to life-threatening sepsis sequela such as multi-organ dysfunction syndrome (MODS), and is accompanied by abnormal levels of pathological and damage-associated molecular patterns (PAMPs & DAMPs) in biological fluids. Activated carbon or charcoal (AC) of new generation with ameliorated biocompatibility has spurred renewed interest in the regulation of these toxins’ levels in inflammation states. (2) Methods: We searched PubMed, Google Scholar, ScienceDirect, Researchgate, and other sources for the relevant literature from 1550 B.C. till 2022 A.C. (3) Results: Laboratory and clinical investigations demonstrate that activated carbon or charcoal (AC) mitigates inflammation in different pathological states when applied orally, per rectum, or in a hemoperfusion system. AC protects the microbiome and bone marrow, acts as an anti-inflammatory and anti-oxidant remedy, and recovers the plasmatic albumin structure. The mechanism of AC action is related to a non-selective (broad-range) or/and selective adsorption of PAMPs & DAMPs from biological fluids. A high-adsorptive capacity towards noxious substances and application of AC as early as possible seems paramount in inflammation treatment for preventing sepsis and/or multi-organ failure. (4) Conclusion: AC could be considered an adjunctive treatment for preventing sepsis and/or multi-organ failure. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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30 pages, 2689 KiB

Open AccessReview

Biochar for Soil Carbon Sequestration: Current Knowledge, Mechanisms, and Future Perspectives

by Simeng Li and Desarae Tasnady

C 2023, 9(3), 67; https://doi.org/10.3390/c9030067 - 7 Jul 2023

Cited by 25 | Viewed by 11292

Abstract

Biochar, a sustainable solid material derived from biomass pyrolysis enriched in carbon, has emerged as a promising solution for soil carbon sequestration. This comprehensive review analyzes the current knowledge on biochar’s application in this context. It begins by examining biochar properties and production [...] Read more.

Biochar, a sustainable solid material derived from biomass pyrolysis enriched in carbon, has emerged as a promising solution for soil carbon sequestration. This comprehensive review analyzes the current knowledge on biochar’s application in this context. It begins by examining biochar properties and production methods, highlighting its recalcitrant nature as a potential stable carbon sink. The influence of various feedstocks and pyrolysis conditions on various physicochemical properties of biochar and its soil carbon sequestration potential is explored. Mechanisms through which biochar enhances soil carbon sequestration are discussed, including its role as a physical barrier against carbon loss and its ability to promote stable soil aggregates and influence soil microorganisms. Challenges and limitations, such as variations in biochar properties and optimal application rates, are addressed, along with strategies for maximizing biochar effectiveness through amendments. The review concludes by emphasizing the importance of long-term field studies, standardized protocols, and economic assessments to support the widespread adoption of biochar for soil carbon sequestration and its potential in climate change mitigation. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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17 pages, 2091 KiB

Open AccessReview

Bonding of Carbon Steel Bars in Concrete Produced with Recycled Aggregates: A Systematic Review of the Literature

by Elvys Dias Reis, Henrique Comba Gomes, Rogério Cabral de Azevedo, Flávia Spitale Jacques Poggiali and Augusto Cesar da Silva Bezerra

C 2022, 8(4), 76; https://doi.org/10.3390/c8040076 - 7 Dec 2022

Cited by 4 | Viewed by 2392

Abstract

Civil construction is essential for the world economy and the largest generator of construction and demolition waste (CDW), mainly due to a lack of planning, technological control, and restoration execution, among other factors. While efforts are made to minimize this waste generation, one [...] Read more.

Civil construction is essential for the world economy and the largest generator of construction and demolition waste (CDW), mainly due to a lack of planning, technological control, and restoration execution, among other factors. While efforts are made to minimize this waste generation, one possible application for CDW is its incorporation into Portland cement-based materials as recycled aggregates, in partial or total replacement of natural aggregates. However, for CDW use to be feasible, the structure performance and safety must be assured, and the adherence between concrete and reinforcement bars, in this context, is a fundamental mechanism. With this perspective, this paper aims to investigate the influence of recycled aggregate on steel–concrete bonding. To this end, the SREE (Systematic Review for Engineering and Experiments) method was employed as a novelty, including a methodology quality analysis, to search and analyze relevant scientific articles published in the last ten years. The results revealed that the use of CDW as recycled aggregates in concrete worsens the steel–concrete bonding, and that ribbed steel bar seems to be the best option when employed in RC structures built with CDW-concrete, although the bar diameter and the anchorage length still need further investigations, and that CDW-concrete’s use can significantly contribute to reducing the emission of greenhouse gases and to capturing CO₂ from the atmosphere. Therefore, further investigations should focus on the real influence of recycled aggregate type and replacement content, bar diameter, anchorage length, and CDW’s potential to capture CO₂. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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19 pages, 5823 KiB

Open AccessReview

Rice-Husk-Based Materials for Biotechnological and Medical Applications

by Gaukhar Smagulova, Aigerim Imash, Akniyet Baltabay, Bayan Kaidar and Zulkhair Mansurov

C 2022, 8(4), 55; https://doi.org/10.3390/c8040055 - 27 Oct 2022

Cited by 4 | Viewed by 4586

Abstract

This review contains the main research directions, which are directly aimed at converting materials based on rice husks particularly, for their role for medicine and biotechnology. Especially in developing countries, more than 95% of rice husks are produced. Although numerous studies have been [...] Read more.

This review contains the main research directions, which are directly aimed at converting materials based on rice husks particularly, for their role for medicine and biotechnology. Especially in developing countries, more than 95% of rice husks are produced. Although numerous studies have been conducted on the production of various materials from rice husks, the existing scientific information is still widely scattered in the literature. Therefore, this review article provides extensive information on the work of various researchers, including the Institute of Combustion Problems (Almaty, Kazakhstan), on the production of various materials from rice husks and their physico-chemical characteristics. The main applications of rice husk materials in medicine are discussed. The ways of prospective conversion of rice husks for biotechnological purposes are considered. Full article

(This article belongs to the Special Issue Carbons for Health and Environmental Protection)

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