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Summary: In order to improve the adsorption properties and stability of porous starch, the porous starch made from ground rice starch was doubly modified by cross‐linking and esterification using sodium trimetaphosphate (STMP) as a cross‐linking agent and octenyl succinic anhydride (OSA) as an esterifying agent. Structural analysis of the samples showed that the phosphate group in STMP formed a new P‐O‐C covalent bond with the hydroxyl group in starch by substitution, OSA combined with the hydroxyl group of starch formed an ester carbonyl group, and all cross‐linking and esterification occurred in the amorphous region of starch. DSC and TG/DTG analysis showed that STMP modification performed better than OSA modification in thermal stability. However, by analysis of the oil absorption properties and freeze–thaw stability, the OSA‐modified porous starch exhibited better oil‐holding rate and freeze–thaw stability. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) and hexagonal boron nitride (h‐BN) monolayer, and h‐BN/WS2 heterojunction with low lattice mismatch is constructed using density functional theory (DFT). The band structures, density of states (DOS), charge density differences (CDD), work function (WF), adsorption energy and adsorption distance of h‐BN/WS2 heterojunction for six gases molecules (CO, CO2, NO, NO2, SO2, and H2S) are systematically discussed. Gas adsorption on one‐side and both‐sides of the heterojunction is considered. The results indicate that the band gap of the heterojunction is lower than that of h‐BN and WS2, indicating that the construction of heterojunction is beneficial for conductivity. For six gases, the adsorption energy of one‐sided adsorption is significantly greater than that of both‐sided adsorption, except for CO2 and NO. The adsorption of NO and NO2 introduces the magnetism into the system. Interestingly, the h‐BN/WS2 heterojunction demonstrates excellent selectivity for NO gas under one‐sided and both‐sided adsorption. The corresponding adsorption mechanism is explored. [ABSTRACT FROM AUTHOR]

In SF6-submerged gas-insulated switchgear that is one of the major components of power-generating systems, it became necessary that it function properly. As time passes, SF6 is decomposed to gas like HF, H2S, SO2, SOF2, and SO2F2. These decomposed remnants and other byproducts CO, CO2, and CF4 need to be detected for the proper function of the power system. The decomposed remnants and other byproducts are sensed via the InTe and doped InTe-F monolayers using density functional theory in this work. The physisorption-type gas sensing is observed by pristine and doped InTe monolayers. The adsorption analysis and electronic properties are calculated. The charge localization and redistribution are calculated by using the electron localization function and charge density difference. The selectivity of the InTe monolayer is understood by the work function. The detection limit of the InTe monolayer is verified by calculating the recovery time. Thus, all of the analyses suggest its potential application in gas-insulated switchgear (GIS). [ABSTRACT FROM AUTHOR]

In this work, we report Na-Fe(III) coordination polymer, Na[Fe(C10H12N2O8)(H2O)]·2H2O (1), derived from Ethylenediaminetetraacetic acid (EDTA) and the compound exhibits distorted octahedral coordination geometry. The polymeric structure is generated when octahedral sodium is connected with five oxygens comes from five EDTA molecules and one water molecule. The specific surface area (SBET) of the compound was measured by Brunauer-Emmett-Teller (BET) which is 1036.9653 m²/g that value is consider as impressive. Further, thermal stability, sorption properties of nitrogen, water and benzene were also examined. In addition, electrical conductivity, the amount of ions and Hirshfeld surface analysis were also studied. The N2 adsorption isotherm displays two distinct stages at low relative pressures (P/P0 = 0-0.02), indicating the presence of two distinct types of nanopores within the material structure. In case of adsorption of water molecules, the adsorption capacity, reaching nearly 29 mol/kg, and achieves saturation at water vapor pressure while the benzene primarily adsorbs onto the outer surface of the sorbent material at 1.38 mol/kg but its adsorption capacity is lower in comparsion to water. This observation indicates that delineating the adsorption texture of the adsorbent material. The cleavage of certain bonds between the polymerized metal and the ligand in the coordination compound is confirmed through electrical conductivity and the amount of ions. The Hirshfeld surface analysis provided information about various types of surfaces interactions in this compound. [ABSTRACT FROM AUTHOR]

[Display omitted] The behavior of cucurbit[6]uril at the electrode/solution interface in the presence of magnesium sulfate was investigated and quantified. It has been established that at the highest positive potential available for the adsorption of organic compounds, a structure is formed that consists entirely of neutral cavitand molecules. [ABSTRACT FROM AUTHOR]

Tannins are the most abundant phenolic compounds after cellulose, hemicellulose, and lignin. Condensed tannins are one class of tannins with diverse functional activities, such as hemostatic and wound healing, anti-inflammatory and anti-allergic behavior. There is a key research topic in the field of plant polyphenols. Banana peel is one of the main by-products of the banana processing industry, which is usually used as animal feed or directly landfilled with a low utilization rate of the functional components. In fact, banana peel can contain many active ingredients, such as condensed tannins. Previous research has been widely used to optimize the extraction parameters for condensed tannins of banana peel. The structural analysis has been conducted to demonstrate their antioxidant, inhibition of Escherichia coli, and anti-hyperglycemic effects. However, the extracted condensed tannins of banana peel are required for purification. Few purification studies have been carried out at present. In this study, macroporous resins were used to purify the condensed tannins of banana peel. A comparison was made on the static adsorption and desorption performance of six macroporous resins. The most suitable resin was selected in this case. Kinetic models, adsorption isotherm, and thermodynamic parameters were then used to analyze the adsorption properties of macroporous resins. A systematic investigation was implemented to clarify the effects of loading concentration, loading flow rate, and volume on adsorption efficiency, as well as the effects of ethanol concentration, elution flow rate, and volume on desorption efficiency. The results showed that the HP-20 macroporous resin shared a high adsorption rate (87.47%) and desorption rate (84.12%), indicating the best purification for the condensed tannins of banana peel. The adsorption kinetics curve demonstrated that the adsorption capacity of tannin on HP-20 resin sharply increased within the first 4 h, thus reaching the maximum adsorption capacity in 8 h, and then maintaining the stability. The desorption kinetics proved that the desorption was essentially realized within 5 h, with a desorption rate of 92.87%. The adsorption curve was fitted to the pseudo-second-order kinetics (R2=0.997 2). Additionally, the adsorption isotherm experiment confirmed that the adsorption of banana peel condensed tannins by HP-20 resin increased, as the temperature raised. Therefore, the higher temperature was favored to the adsorption. The adsorption isotherms curves were fitted using thermodynamic equations. Freundlich thermodynamic model was suitable for the adsorption behavior of banana peel condensed tannins on HP-20, indicating multilayer sorption on a heterogeneous surface. The KF of the Freundlich model increased with the increasing temperature, indicating that the higher temperature was favorable for the adsorption. In both the Langmuir and Temkin models, the parameters RL and KT were used to predict the adsorption from different perspectives. The computed value of RL was less than 1, indicating the favorable adsorption of banana peel condensed tannins onto HP-20 resins. Additionally, KT increased with temperature rising. Consequently, there was a stronger binding energy between condensed tannins and the resin, resulting in a tighter association between them, as temperature increased. Moreover, the thermodynamic parameter was ΔG<0, ΔH=5.13 kJ/mol, ΔS=47.28 J/mol·K. Therefore, the adsorption process was spontaneous and endothermic, with an increased randomness and dominant physisorption. The optimal conditions for purification were determined as the sample concentration of 6 mg/mL, ethanol concentration of 70%, and loading flow rate of 1.5 mL/min, for loading and elution, using volumes of 200 and 120 mL. The purity of banana peel condensed tannins increased from 5.79% to 68.44%. The HP-20 resin and purification conditions were effectively improved for the purity of banana peel condensed tannins. [ABSTRACT FROM AUTHOR]

This is an article in the field of environmental engineering. In this article, the composition, structural characteristics and surface properties of coal gasification crude slag (CGCS) and coal gasification fine slag (CGFS) were characterized by X-ray fluorescence analyzer, scanning electron microscopy, FTIR spectroscopy, specific surface area and pore size analysis, and the results showed that CGFS had a more developed pore size structure and larger specific surface area. The adsorption test results show that the adsorption of n-butyl sodium xanthate by the two coal gasification slags is consistent with the Langmuir adsorption isotherm model and is a spontaneous heat process, which conforms to the quasi-secondary kinetic model, and the adsorption rate constant CGFS > CGCS. Among them, the adsorption performance of CGFS to n-butyl sodium xantho can reach 181.95 mg/g due to CGCS.

With the rapid development of electronics, the application and research of two-dimensional materials have been at the forefront of the world's scientific research. Black phosphorus (BP) has the advantages of large specific surface area, anisotropy, band tunability, high electrical conductivity and high theoretical specific capacity, which make it very promising for research in the fields of medicine, aerospace and electrochemistry. This paper calculates the electronic structure and adsorption properties of BP in water for different heavy metal ions of Pb 2 + , Hg 2 + and Cd 2 + , including adsorption energy, bandgap, electron density and Mulliken population analysis, based on the first-principles approach of density generalized theory. First principles are quantum mechanical calculations based on density functional theory (DFT), which is a dominant well-developed method in the field of materials simulations, with low errors and high efficiency, especially in systems containing metallic particles. The results showed that the Pb 2 + adsorption system in water was more stable than the Hg 2 + adsorption system and the Cd 2 + adsorption system. The bandgap values of 0.617, 0.785 and 0.715 eV of BP after adsorption of Pb 2 + , Hg 2 + and Cd 2 + in water are smaller compared to 0.891 eV of intrinsic BP, and its properties change from direct bandgap semiconductor to indirect bandgap semiconductor. The higher the stability of a system for the adsorption of different heavy metal ions by BP, the higher the internal electron activity of the adsorption system and the amount of electron transfer. Meanwhile, it is concluded that the electrons mainly transfer from P to heavy metal ions in all the adsorption systems. The electron transfer of the BP-Pb 2 + , Hg 2 + , and Cd 2 + adsorption system occurs mainly in the p, s, and s/p orbitals, respectively. The above content investigated the electronic structure changes and internal electron transfer of heavy metal ions adsorbed by black phosphorus in water, expecting to provide a new reference basis for the detection of heavy metal ions in industrial wastewater using black phosphorus. [ABSTRACT FROM AUTHOR]

Biochar (BC) can be coated with microbial extracellular polymeric materials (EPS) to form BC-EPS corona in an aqueous environment, which may significantly alter its ecological toxicity caused by EPS-facilitated accumulation of environmental contaminants. This work examined the EPS corona formation on the surface of shrub branch BC and wheat straw BC, pyrolyzed at 450 °C and 650 °C, and evaluated its effect on the sorption of divalent metals Cd2+, Pb2+, Cu2+, and Ni2+. In single metal systems, the formation of a BC-EPS corona shows little enhancement on Cd2+ and Cu2+ accumulation, but significantly elevated Ni2+ and Pb2+ adsorption: Ni2+ sorption increased from 20 mg/g for pristine BCs to 30 mg/g, Pb2+ sorption increased from below 25 mg/g to above 90 mg/g. In multiple metal systems, the binding distribution of Pb2+ and Cu2+ on BC-EPS corona appeared to be more extensive compared to that of Cd2+ and Ni2+. The toxicity of BC-EPS increased by about 2 to 3 times in aquatic organisms compared to pristine BC, attributed to the higher accumulation of heavy metals in BC-EPS corona. In summary, BC-EPS corona enhanced BC’s sorption capacity for metals, especially for Pb2+ and Ni2+, thus elevating the BC’s ecological risks owing extra amount of pollution loading. [ABSTRACT FROM AUTHOR]

The synthesized carbon-based biphenylene materials have contributed to the recent increase in interest in inorganic biphenylene counterpart. It is expected that the inorganic biphenylene material will have suitable functionalities for different energy harvesting applications. In this study, we conducted first-principles density functional theory (DFT) calculations and thermodynamic analysis to explore the hydrogen (H 2) storage properties of pristine BP-biphenylene (b-BP) and BP-graphenylene (g-BP) monolayers and alkali metals (AM=Li, Na, K) decorated b-BP (labeled as b-BP(AM)) and g-BP (labeled as g-BP(AM)) systems. Both b-BP and g-BP monolayers exhibit a weak affinity for (H 2) molecules. However, b-BP(AM) and g-BP(AM) overcome this limitation and exhibit the ability to adsorb multiple H 2 molecules. The positive charge generated by the AM adatoms is the cause of the neighboring H 2 molecules becoming polarized due to electron transfer to the b-BP and g-BP monolayers. This polarization facilitates their binding through van der Waals interactions, making the surrounding suitable to accommodate a significant amount of H 2 molecules. The storage capacities for b-BP(Li) and g-BP(Li) systems are 9.05 wt% and 6.99 wt% respectively, when operating under practical conditions. Notably, these values exceed the US Department of Energy's target of 5.50 wt% by 2025 and highlight the potential of b-BP(AM) and g-BP(AM) systems as promising materials for hydrogen storage applications. [Display omitted] • The Alkali-metals atoms (AM=Li, Na, K) decorated b-BP and g-BP systems is studied using DFT. • AM binds strongly to b-BP and g-BP monolayers. • The gravimetric H 2 uptake of b-BP(Li) and g-BP(Li) are 9.05 wt% and 6.99 wt% at practical conditions. • The b-BP(AM) and g-BP(AM) materials are the promising for high-performance H 2 storage applications. [ABSTRACT FROM AUTHOR]

Aiming at the existing air suction hole tray seedling sowing machine in the face of more impurities and no pill granulation irregular small particle vegetable seeds there are suction holes clogging and lead to the decline in the accuracy of seed discharge technical problems. In this study, a vegetable seedling planter based on high-voltage electrostatic adsorption characteristics was designed by discarding the small aperture and long conductance suction holes. The dielectric insulating layer material is determined by theoretical analysis and simulation tests of potential contour distribution. The results show that: as the relative dielectric constant of the dielectric insulating layer gradually increases, the distribution of equipotential lines between the type hole and the seed box is gradually dense, the potential difference gradually increases, the electric field is gradually strengthened, and the electrostatic adsorption force on the polarised seeds gradually increases, and the adsorption state becomes more and more stable; Construct a mechanical model of electrostatic adsorption, clarify the main factors affecting the electrostatic adsorption force and their interrelationships. The results show that the main factors affecting the size of the effective electrostatic adsorption force in the pore are the output voltage of the electrostatic generator, the hole machining diameter, the material of the dielectric insulating layer, the relative permittivity of the seed layer, the spacing between the pore and the seed layer, and the material of the electrode sheath and the inner and outer diameters of the pore. And determine the electrical parameters and ranges affecting the seeding performance; A three-factor, three-level Box-Behnken centre combination test was carried out with the hole machining diameter, positive high-voltage electrostatic generator output voltage and tilt angle of the seed box bottom as test factors, and sowing pass index, reseeding index and leakage index as response indicators. The results showed that the order of influence of the test factors on the sowing compliance index was the output voltage of the forward high-voltage electrostatic generator, the hole machining diameter, and the tilt angle of the bottom of the seed box; and the order of influence on the reseeding index and the leakage index was the hole machining diameter, the output voltage of the forward high-voltage electrostatic generator, and the tilt angle of the bottom of the seed box. The interaction terms of the diameter of the pore processing and positive HVEG output voltage had significant effects on seeding pass index, reseeding index and leakage index. Mathematical models were obtained between the test factors and the response indicators. Applying Design-Expert 10.0.4 software to optimise the mathematical regression model with multiple objectives, the best parameter combinations were obtained as follows: the hole machining diameter 5.91 mm, positive high-voltage electrostatic generator output voltage 17.67 kV, and tilt angle of the bottom of the seed box 14.69°, and the sowing qualification index at this time was 91.13%, the reseeding index was 3.02%, and the omission index was 5.85%; In the seeding performance verification test, the seeding pass index decreased by 0.61 percentage points, the reseeding index decreased by 0.17 percentage points and the missed seeding index increased by 0.78 percentage points compared to the optimised results. The test error is within the permissible range, and the parameter optimization results are reliable and meet the technical requirements of precision sowing. The results of the study can provide a reference for the research and development of mechanical equipment for precision sowing of vegetable seeds with irregular small particles, and at the same time, provide an academic reference for the research of quantitative adsorption and rapid separation methods and equipment development of irregular small particles materials. [ABSTRACT FROM AUTHOR]

Good environmental compatibility and excellent insulation performance make trifluoroiodomethane (CF3I) have the potential to replace SF6 in gas-insulated equipment. The gas–solid compatibility of CF3I, its main decomposed products (I2, C2F6, C3F8, C2F4, HF, CF3H, COF2), and environmental molecule H2O with the Al and Cu(111) surfaces is investigated based on first-principles calculations. The most stable adsorption configurations of Al and Cu(111) surfaces adsorbed by all gas molecules are constructed, and the interaction types between gas molecules and two metal surfaces are determined by adsorption energy (E ad), charge transfer, and charge density difference. The absolute E ad of CF3I and I2 adsorbed on Al(111) surfaces are 4.09 and 3.76 eV, respectively. In contrast, the absolute E ad of other gases adsorbed on Al(111) surfaces do not exceed 0.99 eV, indicating that CF3I and I2 have strong chemical interactions and poor gas–solid compatibility with Al(111) surfaces, while other gases exhibit good gas–solid compatibility with the Al surface. The absolute E ad of I2 (1.15 eV) adsorbed on Cu(111) surface is significantly larger than that of other gases-adsorbed systems (not exceeding 0.99 eV) including CF3I-adsorbed system, proving that the gas–solid compatibility of I2 with Cu(111) surfaces is worse than that of other gases. In addition, the reasons for the different compatibility of CF3I with Al and Cu(111) surfaces are analyzed in depth through the density of states. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are considered as desirable solid porous materials used for hydrogen storage under moderate conditions owing to their fascinating structural features, but the adsorption properties need to be further improved. In this study, the microstructure of Cu&Li-based MOF was proposed and established based on the structural optimization and Li+ modification of Cu-based MOF, and hydrogen adsorption properties such as the adsorption sites, adsorption isotherms and isosteric heat were investigated by means of grand canonical monte carlo (GCMC) simulations. The results indicate that, due to the structural optimization and doping of the ions, the gravimetric and volumetric H 2 adsorption capacities for Cu&Li-based MOF system can be improved by 56.52% and 47.59% at 218 K under 1000 kPa compared with the Cu-based MOF. The isosteric heat of H 2 adsorption can be improved by 3.13% and 6.85% under 211 kPa and 1000 kPa at 218 K compared with the Cu-based MOF system. The hydrogen adsorption capacity of Cu-based MOF can be well improved based on the optimization strategy. The microscopic mechanism of the adsorption can be attributed to the increased free volume of the MOF system and the higher adsorption energy of Li+ for hydrogen. This study is expected to be meaningful for structural design and gas storage performance further improvement of MOF materials. Microscopic model construction of LA-CuO based CPCM. [Display omitted] • Microstructure of Cu&Li-based MOF was proposed and established. • Structural optimization and Li + modification of Cu-based MOF was performed. • Microscopic improvement mechanism of hydrogen storage performance was explored. [ABSTRACT FROM AUTHOR]

To utilize Cu-benzene-1,3,5-tricarboxylate (Cu-BTC) adsorbed lubricant oils in the self-lubricating field, the adsorption properties of Cu-BTC on different 1-olefins must be clarified. In this work, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, and 1-dodecene were studied by the Monte Carlo method and experimentally. The adsorption limit of Cu-BTC for n-olefins was determined as 1-undecene by the adsorption isotherms. This suggested a limit for even straight-chain molecules to the adsorption of Cu-BTC. The maximum ratio of the olefin length of the largest pore diameter (L/D) of Cu-BTC was approximately 1.57. Furthermore, theoretical calculations (radial distribution function (RDF)) and experiments (infrared (IR) spectra) confirmed the interaction of n-olefin adsorbates and the Cu-BTC framework occurred between the -CH= of olefins and the Cu and O atoms of the Cu-BTC framework. This work adds to the understanding and investigation of the adsorption of liquid lubricants using Cu-BTC as a metal-organic framework (MOF). [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore an effective method to improve the adsorption property of maize starch granules, ultrasonic pretreatment at different temperatures (0, 25, 45, and 65 ℃) below the gelatinization temperature combined with α-amylase was used to modify maize starch. The results showed that after ultrasonic pretreatment, the surface of starch granules became rough with grooves on it. The molecular mass, relative crystallinity and short-range molecular order of the starch samples were significantly decreased (P < 0.05). Compared with single enzymatic hydrolysis, the combinatorial treatment increased the specific surface area and pore capacity of starch consequently improving its adsorption performance. With an increase in the pretreatment temperature from 0 to 65 ℃, the water- and oil-adsorbing capacities of starch granules subjected to the combinatorial treatment increased from 114.71% and 142.16% to 144.77% and 189.70%, respectively. Therefore, ultrasonic treatment at high temperature below the gelatinization temperature combined with α-amylase could be an effective method to prepare a green and high efficiency starch-based adsorbent. This study will be helpful for better understanding of the mechanism by which ultrasonic treatment promotes the enzymatic hydrolysis of starch and will provide a theoretical basis for the development of high-efficiency starch-based adsorbents.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

C5F10O has been put into practical application as a new environmental protection insulating gas that can replace SF6. Partial discharge and other faults will inevitably occur in the insulation equipment, resulting in the decomposition of C5F10O to produce harmful components such as weak insulation CF4, C2F6 and highly toxic CF2O, HF, etc. In order to ensure the safe operation of insulation equipment, these decomposition components need to be selectively removed by adsorption. The new graphene-like C3N material has a good application prospect in the field of gas detection. In this paper, the adsorption process of CuO-C3N on the main decomposition components CF4, C2F6 and highly toxic products CF2O and HF is calculated based on the first-principle. The adsorption energy, density of states, charge transfer amount, differential charge density and recovery time at different ambient temperatures are calculated and analyzed. The results show that CuO-C3N has good adsorption for HF, followed by CF2O, but it can not adsorb CF4 and C2F6. Therefore, CuO-C3N can be used as a high-performance gas adsorbent to remove the highly toxic HF gas in C5F10O insulation equipment. [ABSTRACT FROM AUTHOR]

Nanofibers have the advantages of high strength, high specific surface area, ultra-fine size, high flexibility and biocompatibility, and are widely used in various fields. Polyacrylonitrile/carbon nanotube (PAN/CNTs) composite nanofibers with adsorption function for volatile organic compounds (VOCs) were prepared based on electrospinning technology. By optimizing the experimental parameters, such as spinning solution concentration, spinning voltage and receiving plate distance, the most suitable combination of parameters for PAN fibers in the electrospinning process was explored. The results show that when the concentration of spinning solution is 12%, the spinning voltage is 18 kV. When the distance between the receiving plates is 14 cm, the morphology of PAN fibers is regular, the size is uniform, and the average diameter is 200 nm. After the addition of CNTs, the fiber diameter increases to 400 nm, but the structure of PAN does not change. When the content of CNTs is 3%, the morphology of the fibers is the best. The adsorption experiment of VOCs shows that the adsorption efficiency of PAN fiber membrane for xylene gas increased to about 90% by the introduction of CNTs. [ABSTRACT FROM AUTHOR]

Iron hydroxyl sulfate minerals (IHSMs, including schwertmannite and jarosite) are a promising material for environmental applications with excellent adsorption of metal oxygen anions. The acid mine drainage (AMD) abundant in iron and sulfate ions holds potential for the production of valuable IHSMs, thereby achieving resource recycling whilst simultaneously mitigating water contamination, which is important for the sustainable remediation of AMD. Conventional mineralization, which promotes the generation of minerals from Fe3+ and SO42− through the energy provided by chemical or biological oxidation, can only partially mineralize iron in AMD containing substantial quantities of Fe2+. In this study, an improved method for mineralizing AMD containing iron of a different valence into IHSMs under the induction of KHCO3 was proposed. For AMD containing Fe2+, the combination of KHCO3 and H2O2 was used to promote the hydrolysis of iron (92.7%) and sulfate (11.1%) into IHK minerals, which resulted in a significant increase in iron removal of 75.2% and a minor increase in sulfate removal of 4.9%, compared with the formation of schwertmannite from oxidation solely involving H2O2. For the AMD containing Fe3+, the energy generated by the acid–base reaction in water could also directly promote the formation of IK minerals from 97.2% iron and 6.9% sulfate. XRD and FTIR analyses confirmed the identification of the IHK and IK minerals as IHSMs transitioning from schwertmannite to jarosite. SEM and elemental analyses indicated that the mineral exhibited denser aggregate spheres with the incorporation of KHCO3 in mineralization yet displayed enhanced mineralization abilities for the contaminant ions in AMD. Moreover, despite the SSA of the modified minerals being diminished (2.02, 1.83 and 1.83 m2/g for IH, IHK and IK, respectively), the presence of more sulfate in the mineral enhanced the adsorption capacity of Cr(VI). Furthermore, the water quality results also illustrated that the removal ratios of iron and sulfate in AMD notably increased with the involvement of KHCO3 in mineralization. In conclusion, the KHCO3-induced mineralization of iron-containing (either divalent or trivalent) AMD into IHSMs not only improved the mineralization ratios and contaminant removal ratios for better remediation of AMD but also obtained mineral resources with better adsorption of Cr(VI), thereby fostering the sustainable advancement of the remediation of AMD. Therefore, this innovative strategy employing KHCO3-assisted chemical mineralization to form IHSMs holds ample potential and promises to be an efficacious methodology for the sustainable remediation of iron-rich AMD. [ABSTRACT FROM AUTHOR]

The current research status and progress of many domestic and foreign metal oxide nanomaterials adsorbents in the field of arsenic removal are reviewed, and the material compositions, physical phase properties, adsorption mechanisms, adsorption capacities, and applications of different types of metal oxide nanomaterials are systematically summarized. The applications of single, binary and ternary metal oxide nanomaterials in the field of arsenic removal are elaborated. The specific surface area, adsorption capacity, arsenic removal efficiency, applicable pH range and other indicators of different metal oxide nanomaterials are compared to assess the advantages and disadvantages of the materials' arsenic removal performance, and the main adsorption mechanisms are discussed. It also summarizes the problems faced by the current arsenic removal technology of nano-metal oxide adsorbents, such as the difficulty of conversion and application, poor regeneration performance, etc., and puts forward the future development countermeasures and suggestions of nano-metal oxide adsorbents with certain reference value, such as the synergy of multi-metal, the cooperation of multiple mechanisms, and the optimization of the design of proprietary nano-metal oxide adsorbents. [ABSTRACT FROM AUTHOR]

In this study, a modified synthetic zeolite adsorbent was synthesized by the hydrothermal method using coal fly ash as the main raw material, and the enhanced phosphorus adsorption properties from aqueous solutions were then evaluated. The modification parameters were specifically studied and optimized. Moreover, the effects of initial phosphorus concentration, adsorption time, and pH value on phosphorus absorption were also investigated. The adsorbent was characterized by the energy-dispersive spectrometer analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. Furthermore, the phosphorus adsorption properties of the zeolite adsorbent were preliminarily discussed through the perspectives of isothermal adsorption experiments, adsorption kinetics experiments, and adsorption thermodynamics calculations. The results show that the lanthanum ions were physically loaded on the surface and micropores of the adsorbent after modification, which helps to enhance the adsorption effect of phosphorus components from the aqueous solution. The phosphorus removal rate has been increased by about 65%. The adsorption process better fitted the Langmuir and Elovich equations. The theoretical calculation and analysis of adsorption thermodynamics showed that the adsorption and removal of phosphorus in water happens spontaneously.

In this paper, the feasibility of multi-walled carbon nanotube (MWCNT)-modified clay as a landfill liner material is investigated. Experiments were conducted on the modified clay with 0.5%, 1%, and 2% MWCNTs. The effects of the MWCNTs on the compaction characteristics, permeability coefficient, stress–strain curve, peak deviation stress, shear strength parameters (internal friction angle and cohesion), microstructures, and adsorption performance of the clay were analyzed. The results showed that the optimum moisture content (OMC) increased from 16.15% to 18.89%, and the maximum dry density (MDD) decreased from 1.79 g/cm3 to 1.72 g/cm3 with the increase in MWCNTs. The permeability coefficients firstly fell and then gradually rose as the MWCNTs increased; the minimum permeability coefficient was 8.62 × 10−9 cm/s. The MWCNTs can also effectively increase the peak deviation stress of the clay, and at the maximum level, the peak deviation stress was increased by 286%. SEM images were processed using the Pore and Crack Analysis System (PCAS), and the results showed that the appropriate amount of MWCNTs could fill the pores and strengthen the clay structure. The effect of the MWCNT-modified clay on the adsorption performance of common heavy metal ions Cd2+, Mn2+ and Cu2+ in landfill leachate was analyzed by batch adsorption tests. The maximum adsorption capacities (Qmax) of Cu2+, Cd2+ and Mn2+ in the 2% MWCNT-modified clay were, respectively, 41.67 mg/g, 18.69 mg/g, and 4.97 mg/g. Compared with the clay samples without MWCNTs, the adsorption properties of Cu2+, Cd2+, and Mn2+ were increased by 228%, 124%, and 202%, respectively. Overall, the results suggest that MWCNT-modified clays have the potential to be suitable barrier materials for the construction of landfills. [ABSTRACT FROM AUTHOR]

Copyright of Packaging & Food Machinery is the property of Packaging & Food Machinery Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to provide new ideas for solving the problems of large leakage of template molecules and screening of functional monomers in the construction and application of molecularly imprinted polymers of citrinin. 1-hydroxy-2-naphthoic acid was used as a pseudo-template molecule, and a simultaneous determination of citrinin and 1-hydroxy-2-naphthoic acid was established based on liquid chromatography, which had a good recovery (! 95%) for molecularly imprinted eluent and could also separate citrinin from the alcohol extract of functional Hongqu. The functional monomer 2,6 -diaminopyridine for the construction of molecularly imprinted polymer was optimized by the quantum chemical method through molecular configuration optimization, atomic charge distribution, and binding energy calculation. The preparation process of the imprinted polymer was optimized by response surface methodology. The adsorption capacity of the optimized polymer to citrinin was as high as (195.10 ± 13.21) ng/g, which was 0.79 times higher than that before optimization. Finally, the adsorption properties of the optimized polymer and the control polymer were compared with the polymer constructed with methacrylic acid as a functional monomer. The adsorption capacity of the former to citrinin was three times that of the latter, which confirmed the practicability of computer simulation in the construction of citrinin molecularly imprinted polymer. This study aimed to provide references for the construction of molecularly imprinted polymers and the enrichment and detection of citrinin. [ABSTRACT FROM AUTHOR]

A magnesium aluminum bimetallic organic framework derivative (MgAl-DHBDC/LDH composite) was prepared by etching MgAl bimetallic MOF template and used to remove U(VI) in aqueous solution. Compared to MgAl-DHBDC, the stability, dispersibility and removal ratio of U(VI) with MgAl-DHBDC/LDH were improved significantly over a wide pH range. The adsorption of uranium by MgAl-DHBDC/LDH was mainly multilayer physical adsorption, and the adsorption process was a spontaneous endothermic process. Moreover, the removal ratio of U(VI) by the MgAl-DHBDC/LDH composite remained above 90% after 4 cycles, indicating good regeneration performance. The MgAl-DHBDC/LDH composite shows great potential in the remediation of radionuclide uranium wastewater. [ABSTRACT FROM AUTHOR]

BACKGROUND: Self‐propagating high‐temperature synthesis was used to create mesoporous CeO2 and MgO powders as well as nanocomposites based on them for efficient degradation of organic dyes. RESULTS: It has been investigated how magnesium oxide and cerium oxide interact to affect the crystal structure, morphology and microstructure of the materials produced. It was assumed that CeO2 forms on the surface of MgO while the material's developed surface is preserved. The values of the specific surface area and average pore diameter of the studied samples depend on the composition and vary in the ranges of 16–41 m2 g−1 and 11.919 nm, respectively. CONCLUSION: It has been established that the sizes of CeO2 crystallites in the composition of nanocomposites change insignificantly and range from 6.5 to 7.4 nm. The photocatalytic activity of the studied samples is at least two times higher compared to analogs. The samples MgO–CeO2 (30 mol%) and MgO–CeO2 (50 mol%) showed the maximum photodegradation efficiency of acid telon blue and direct bright blue dyes at levels of 98.5% and 92.5%, respectively. © 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Abstract To utilize Cu-benzene-1,3,5-tricarboxylate (Cu-BTC) adsorbed lubricant oils in the self-lubricating field, the adsorption properties of Cu-BTC on different 1-olefins must be clarified. In this work, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, and 1-dodecene were studied by the Monte Carlo method and experimentally. The adsorption limit of Cu-BTC for n-olefins was determined as 1-undecene by the adsorption isotherms. This suggested a limit for even straight-chain molecules to the adsorption of Cu-BTC. The maximum ratio of the olefin length of the largest pore diameter (L/D) of Cu-BTC was approximately 1.57. Furthermore, theoretical calculations (radial distribution function (RDF)) and experiments (infrared (IR) spectra) confirmed the interaction of n-olefin adsorbates and the Cu-BTC framework occurred between the -CH= of olefins and the Cu and O atoms of the Cu-BTC framework. This work adds to the understanding and investigation of the adsorption of liquid lubricants using Cu-BTC as a metal-organic framework (MOF).

Rapeseed straw, bagasse, and walnut peel have a large amount of resource reserves, but there are few technologies for high value-added utilization. In the research of biochar, walnut green husk is rarely used as raw material. In addition, the three main components of biomass (lignin, cellulose, and hemicellulose) are present in similar proportions, and the differences between the physical and chemical properties of biochar prepared with similar amounts of biomass raw materials are not clear. Using three kinds of biomass of the same quality as raw materials, biochar was prepared via pyrolysis at 400 °C, and activated carbon was prepared via CO2 activation at 800 °C. The results showed that the pore numbers of the three kinds of biochar increased after activation, resulting in the increase of the specific surface area. The resulting numbers were 352.99 m2/g for sugarcane bagasse biochar (SBB)-CO2, 215.04 m2/g for rapeseed straw biochar (RSB)-CO2, and 15.53 m2/g for walnut green husk biochar (WGB)-CO2. Ash increased the amount of carbon formation, but a large amount of ash caused biochar to form a perforated structure and decreased the specific surface area (e.g., WGB), which affected adsorption ability. When the three main components were present in similar proportions, a high content of cellulose and lignin was beneficial to the preparation of biochar. The adsorption value of MB by biochar decreased with the increase of biomass ash content. After activation, the maximum adsorption value of MB for bagasse biochar was 178.17 mg/g, rapeseed straw biochar was 119.25 mg/g, and walnut peel biochar was 85.92 mg/g when the concentration of methene blue solution was 300 mg/L and the biochar input was 0.1 g/100 mL at room temperature. The adsorption of MB by biochar in solution occurs simultaneously with physical adsorption and chemical adsorption, with chemical adsorption being dominant. The optimal MB adsorption by SBB-CO2 was dominated by multimolecular-layer adsorption. This experiment provides a theoretical basis for the preparation of biochar and research on its applications in the future. [ABSTRACT FROM AUTHOR]

Excessive nutrient phosphorus in water can cause eutrophication, affecting ecosystems, human health, and socioeconomics. Using plants to prepare biochar can not only effectively adsorb phosphate in water, but also realize the utilization of waste resources. In this paper, reed biochar was prepared to explore its physical characteristics and phosphorus adsorption characteristics. The results are as follows: (1) the surface of reed biochar is distributed with a large number of irregular granular protrusions, with large specific surface area, many pores, and functional group such as hydroxyl groups; (2) phosphorus adsorption experiments with different variables were set up, and the optimum addition amount and pH for phosphorus removal by reed biochar were obtained; (3) the kinetic fitting data showed that the pseudo-second-order kinetic model could better describe the reed biochar; and (4) the adsorption isotherm data showed that the adsorption process conforms to the Langmuir and Freundlich isotherm adsorption models at the same time. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By radical polymerization, two series of superabsorbent hydrogels of hydroxybutyl acrylate and acrylamide copolymers, poly(HBA-co-AAm), were obtained. In the first series, the ratio of hydroxy-butyl acrylate to acrylamide was optimized with aconstant amount of methylene bisacrylamide (MBA) as across-linking agent. In the second series, the amount of MBA was changed at afixed monomer ratio. The structure of the copolymers was confirmed by the FTIR method. Swelling parameters and mechani-cal properties were tested. Hydrogels with ahigh Young’s modulus and ahigh degree of swelling were selected for the study of adsorption properties towards Co2+, Ni2+ and Cd2+ ions. The influence of basic factors such as adsorbent dose, exposure time and pH on adsorption efficiency was also investigated. The ability to adsorb heavy metal ions changed as follows: Co2+> Ni2+> Cd2+.

Granular activated carbon (GAC) and powdered activated carbon (PAC) are the two most common forms of activated carbon with varying particle size range. The goal of this study was to analyze the key factors (particle size and activation temperature) affecting the surface characteristics of GAC and PAC derived from palm kernel shell (PKS). The surface morphology suggested that the pore network in PKS-PAC is more developed than that in PKS-GAC owing to the presence of a micropore structure when prepared at lower activation temperatures. This study also demonstrated that activation performed on different PKS particle size range influenced the mesopore domain of the activated carbon produced. The PKS-GAC was found to have more mesopores than PKS-PAC, which made it more reliable for dye adsorption in water treatment. Overall, this study demonstrated that applying different particle size range of PKS during the activation process can have a significant influence on the surface characteristics, thus having a direct impact on the application of activated carbon. An accurate particle size range will ensure that the most cost-effective activated carbon is selected to achieve the desired performance objectives.

In this paper, MFe2O4 (M = Ca, Mg and Ni) ferrite graphene oxide composites (MFe2O4-GO) were prepared by a one-pot solvothermal reaction. MFe2O4-GO and MFe2O4 were characterized by high-resolution transmission electron microscope, X-ray diffraction, thermogravimetric and Fouriertransform infrared spectroscopy. The adsorption performance of MFe2O4 and MFe2O4-GO were studied using acridine orange as model. The influence factors of adsorption performance such as pH, adsorption time, initial concentration, NaCl concentration and reusability were investigated. The experimental results revealed that the adsorption capacity of MFe2O4-GO for acridine orange was significantly higher than that of MFe2O4. It can be found that the adsorption capacity of different MFe2O4-GO in the following order: MgFe2O4-GO > NiFe2O4-GO > CaFe2O4-GO. The adsorption process of MFe2O4-GO for acridine orange conforms to the pseudo-second-order kinetic model and Freundlich isothermal model. MFe2O4-GO can be reused five times. The adsorption interaction of acridine orange with MFe2O4-GO is mainly electrostatic attraction. MFe2O4-GO has practical application value in wastewater treatment as adsorbent. [ABSTRACT FROM AUTHOR]

Construction of metal oxide nanoparticles on ZIF-8 has produced many novel hybrid materials with interesting properties, of which ZnO-ZIF-8 is a typical representative. However, due to the powdered crystalline state of ZnO-ZIF-8 hybrid materials, their processability and handling remain a significant challenge. In this work, a multifunctional ZnO-ZIF-8/bamboo composite was successfully fabricated through in-situ growth of spherical ZnO-ZIF-8 hybrid nanoparticles within natural bamboo substrates. At a 6.8 wt% ZnO-ZIF-8 loading, the resulting composite displays highly removal efficiency up to 97.6% for methylene blue (MB) and the adsorption capacity can reach 226.7 mg·g−1 at 298 K. The MB removal efficiency dropped to 96.0% after five cycles, revealing the composite exhibited an excellent recyclability. Furthermore, the introduction of ZnO-ZIF-8 remarkably enhanced the thermal stability and flame retardancy of the natural bamboo. Compared with the untreated natural bamboo, the peak of heat release rate of the ZnO-ZIF-8/bamboo composite exhibited a drastic decline by 61.6% from 45.3 W·g−1 to 17.4 W·g−1 and the total heat release from 7.6 kJ·g−1 to 4.4 kJ·g−1. This work offers a new avenues for designing and constructing functionalized MOFs@bamboo composite that may boost their environmental- and green building-related applications. [ABSTRACT FROM AUTHOR]

The adsorption properties of powdered and composite sorbents in sorption from dilute solutions and in sorption of oils were studied. Acetic acid solutions and such oils as liquid paraffin and MS-20 industrial oil were chosen as examples. The sorbents were based on thermally expanded graphite prepared from hydrolysis lignin using thermal and electrochemical technologies. High adsorption performance of thermally expanded graphite and its ability for regeneration after the sorption from solutions were proved. The influence of the density of the composite sorbents on their ability to adsorb oils was examined. An equation was obtained for calculating the oil absorption coefficient after keeping the composite sorbents in oils for different times, and the constants of this equation, which depend on the sorbent density and kind of oil, were calculated. [ABSTRACT FROM AUTHOR]

[Display omitted] The influence of the electrolyte nature and cation charge on the adsorption properties of cucurbit[6]uril supramolecular complexes are established and discussed. The results show the narrowing of the adsorption potential region of these complexes with increasing cation charge, and the possibility to form an adsorbate layer of supramolecular cations associated with surface-active electrolyte anions at the positive boundary of the adsorption potential region. [ABSTRACT FROM AUTHOR]

To study the importance of the adsorption mechanism of methane (CH4) and carbon dioxide (CO2) in coal for coalbed methane development, we aimed to reveal the influence mechanism of adsorption pressure, temperature, gas properties, water content, and other factors on gas molecular adsorption behavior from the molecular level. In this study, we selected the nonsticky coal in Chicheng Coal Mine as the research object. Based on the coal macromolecular model, we used the molecular dynamics (MD) and Monte Carlo (GCMC) methods to simulate and analyze the conditions of different pressure, temperature, and water content. The change rule and microscopic mechanism of the adsorption amount, equal adsorption heat, and interaction energy of CO2 and CH4 gas molecules in the coal macromolecular structure model establish a theoretical foundation for revealing the adsorption characteristics of coalbed methane in coal and provide technical support for further improving coalbed methane extraction. [ABSTRACT FROM AUTHOR]

CuFe2O4 nanoparticles were synthesized via the sol–gel auto combustion method—their hybrid nanocomposite with layer-structured graphene. X-ray diffraction results confirmed the crystallite size of CuFe2O4 nanoparticles up to 53 nm. The standard deviation in crystallite size ranges from 34.57 nm of 20% copper ferrite to 53 nm of pure copper ferrite. Fourier transform infrared spectroscopy results confirm three distinct peaks at 1649 cm−1, 1579 cm−1, and 589 cm−1 corresponding to C = O related to carboxyl stretching, C = C related to aromatic stretching, and Fe–O, respectively. Scanning electron microscopy images demonstrate the surface morphology of CuFe2O4 nanoparticles and their nanocomposite. Vibrating sample magnetometer results illustrate that the pure crystal structure of magnetic CuFe2O4 nanoparticles has magnetic saturation (Ms) of ~ 16.69 emu/g with a considerable remanence of around 29.22 emu/g. Energy dispersive X-ray spectroscopy confirms the qualitative and quantitative contents of ferrites and graphene in nanoparticles and nanocomposites. Brunauer–Emmett–Teller surface area analysis results show that the specific surface area increases from 10.88 to 288.5 m2/g by increasing the polymer concentration. Pore size has been calculated between 2.6 and 3.1 nm which shows that the synthesized nanoparticles are in the mesoporous range. The prepared composite was explored for adsorption of As(III) and As(V) from aqueous media for practical applications. The results demonstrate excellent adsorption capacities attributed to the synergistic role of CuFe2O4 and graphene sheets. [ABSTRACT FROM AUTHOR]

Four contrasting types of waste biomass were subjected to matching treatments to prepare biochar for the potential removal or immobility Cr(VI) in polluted water or soil. Rice straw (RS), rice husk (RH), kraft lignin (KL), and cow dung (CD) were selected. The resulting biochars were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and N2 adsorption-desorption isotherms. The physicochemical properties of biochars, such as pH value, ash, yield, and cation exchange capacity (CEC) were also determined. The results showed that the biochars were alkaline, except for the KL biochar (KLBC), which was weakly acidic. Furthermore, the order of CEC was cow dung biochar (CDBC) > rice straw biochar (RSBC) > rice husk biochar (RHBC) > KLBC. FTIR showed that there are abundant oxygen-containing functional groups on the surface of the biochars, with the total amount almost the same, and the structure was dominated by aromatic ring skeleton. The KLBC with micro-nano structure exhibited higher surface area (111 m2/g) than the other BC samples. The Cr(VI) removal followed the order: KLBC > CDBC > RHBC > RSBC.

The pollution and scarcity of freshwater resources are global problems that have a significant influence on human life. It is very important to remove harmful substances in the water to realize the recycling of water resources. Hydrogels have recently attracted attention due to their special three-dimensional network structure, large surface area, and pores, which show great potential for the removal of pollutants in water. In their preparation, natural polymers are one of the preferred materials because of their wide availability, low cost, and easy thermal degradation. However, when it is directly used for adsorption, its performance is unsatisfactory, so it usually needs to be modified in the preparation process. This paper reviews the modification and adsorption properties of polysaccharide-based natural polymer hydrogels, such as cellulose, chitosan, starch, and sodium alginate, and discusses the effects of their types and structures on performance and recent technological advances. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The practical application of metal-organic framework (MOF) crystals is commonly limited by their powder form. In this work, natural balsa wood was employed as substrate for dispersing and shaping MOF particles. A series novel MOF@wood (MOF=UiO-66,ZIF-8 and ZIF-67) composite were successfully fabricated by a facile in situ growth strategy. The microstructure, flame-retardant and methylene blue (MB) dye adsorption behavior of the obtained composite were investigated. The result indicated that the MOF microparticles with different grain sizes and morphologies were uniformly decorated on the lumen surface within the balsa wood scaffold, and MOF crystals maintained its crystallinity in the MOF@wood composite. The ZIF-8@wood composite displays highly removal efficiency up to 82.5%% for methylene blue and the adsorption capacity can reach 210.9 mg/g. Moreover, the adsorption process fits well with a pseudo second-order model, which confirms that the interaction between MOF@wood and MB is mainly controlled by chemical processes.In addition, the incorporation of UiO-66 MOF has better effect on thermal stability at the early stage and char layer formatting of wood substrate than ZIFs.Compared with the untreated wood, the peak of heat release rate of the UiO-66@wood composite exhibited a drastic decline from 94.5 W/g to 36.5 W/g and the total heat release from 7.7 kJ/g to 5.4 kJ/g. Meanwhile, the char residue rate of the UiO-66@wood at 800 ℃ is significantly increased by 84.8%.This work offers a new avenues for designing and constructing functionalized MOF@wood composite that may boost their environmental-and green building-related applications. [ABSTRACT FROM AUTHOR]

In this paper, the feasibility of multi-walled carbon nanotube (MWCNT)-modified clay as a landfill liner material is investigated. Experiments were conducted on the modified clay with 0.5%, 1%, and 2% MWCNTs. The effects of the MWCNTs on the compaction characteristics, permeability coefficient, stress–strain curve, peak deviation stress, shear strength parameters (internal friction angle and cohesion), microstructures, and adsorption performance of the clay were analyzed. The results showed that the optimum moisture content (OMC) increased from 16.15% to 18.89%, and the maximum dry density (MDD) decreased from 1.79 g/cm3 to 1.72 g/cm3 with the increase in MWCNTs. The permeability coefficients firstly fell and then gradually rose as the MWCNTs increased; the minimum permeability coefficient was 8.62 × 10−9 cm/s. The MWCNTs can also effectively increase the peak deviation stress of the clay, and at the maximum level, the peak deviation stress was increased by 286%. SEM images were processed using the Pore and Crack Analysis System (PCAS), and the results showed that the appropriate amount of MWCNTs could fill the pores and strengthen the clay structure. The effect of the MWCNT-modified clay on the adsorption performance of common heavy metal ions Cd2+, Mn2+ and Cu2+ in landfill leachate was analyzed by batch adsorption tests. The maximum adsorption capacities (Qmax) of Cu2+, Cd2+ and Mn2+ in the 2% MWCNT-modified clay were, respectively, 41.67 mg/g, 18.69 mg/g, and 4.97 mg/g. Compared with the clay samples without MWCNTs, the adsorption properties of Cu2+, Cd2+, and Mn2+ were increased by 228%, 124%, and 202%, respectively. Overall, the results suggest that MWCNT-modified clays have the potential to be suitable barrier materials for the construction of landfills.

We investigated the adsorption properties and the dielectric behavior of a very well-known metal-organic framework (MOF), namely Cu3(BTC)2 (known as HKUST-1; BTC = 1,3,5-benzenetricarboxylate), before and after protection with some amines. This treatment has the purpose of reducing the inherent hygroscopic nature of HKUST-1, which is a serious drawback in its application of as low-dielectric-constant (low-κ) material. Moreover, we investigated the structure of HKUST-1 under a strong electric field, confirming the robustness of the framework. Even under dielectric perturbation, the water molecules adsorbed by the MOF remained almost invisible to X-ray diffraction, apart from those directly bound to the metal ions. However, the replacement of H2O with a more visible guest molecule such as CH2Br2 made the cavity that traps the guest more visible. Finally, in this work we demonstrate that impedance spectroscopy is a valuable tool for identifying water sorption in porous materials, providing information that is complementary to that of adsorption isotherms.