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Infrared (IR) action spectroscopy is utilized to characterize carbon-centered hydroperoxy-cyclohexyl radicals (·QOOH) transiently formed in cyclohexane oxidation. The oxidation pathway leads to three nearly degenerate ·QOOH isomers, β-, γ-, and δ-QOOH, which are generated in the laboratory by H-atom abstraction from the corresponding ring sites of the cyclohexyl hydroperoxide (CHHP) precursor. The IR spectral features of jet-cooled and stabilized ·QOOH radicals are observed from 3590 to 7010 cm−1 (∼10–20 kcal mol−1) at energies in the vicinity of the transition state (TS) barrier leading to OH radicals that are detected by ultraviolet laser-induced fluorescence. The experimental approach affords selective detection of β-QOOH, arising from its significantly lower TS barrier to OH products compared to γ and δ isomers, which results in rapid unimolecular decay and near unity branching to OH products. The observed IR spectrum of β-QOOH includes fundamental and overtone OH stretch transitions, overtone CH stretch transitions, and combination bands involving OH or CH stretch with lower frequency modes. The assignment of β-QOOH spectral features is guided by anharmonic frequencies and intensities computed using second-order vibrational perturbation theory. The overtone OH stretch (2νOH) of β-QOOH is shifted only a few wavenumbers from that observed for the CHHP precursor, yet they are readily distinguished by their prompt vs slow dissociation rates to OH products. [ABSTRACT FROM AUTHOR]

We have studied diffusion and thermodiffusion in the ternary system polystyrene + toluene + cyclohexane over the entire composition range of the binary solvent toluene + cyclohexane and for polymer concentrations up to 0.1 mass fractions by multi-color optical beam deflection. The polystyrene molar masses were 4.88 and 17.90 kg/mol. The inversion problem of the contrast factor matrix could be avoided by reasonable a priori assumptions about the diffusion eigenvectors. The fast mode of the bimodal dynamics is attributed to the interdiffusion of the two solvents at constant polymer concentration, whereas the slow mode is due to the diffusion of the polymer with respect to the binary solvent. The amplitude of the fast mode vanishes in the pure toluene and the pure cyclohexane limits of the mixed solvent. The amplitude of the slow mode increases with polymer concentration. The composition and temperature dependence of the slow diffusion eigenvalue, the hydrodynamic correlation length, and the Soret coefficient of the polymer reflect the transition from a good to a theta solvent with increasing cyclohexane content and with decreasing temperature. Due to cross diffusion, cyclohexane reverses its migration direction between the fast and the slow mode, leading to a positive thermodiffusion but a negative Soret coefficient. The polymer thermodiffusion coefficients during the slow mode vary by approximately a factor of two, depending on the solvent composition. Rescaling with the solvent viscosity collapses all data onto a single master curve with an extrapolated value of ηDT ≈ 6 × 10−15 Pa m2 K−1 in the dilute limit. This value is well known from various other binary polymer/solvent mixtures. [ABSTRACT FROM AUTHOR]

In the production of cyclohexene by benzene hydrogenation, the by-product cyclohexane forms an azeotrope with cyclohexene. For the extraction and distillation of the binary azeotrope (cyclohexene + cyclohexane), the selectivity and relative volatility of 24 different entrainers were compared and the intermolecular interaction forces and interaction energies were analyzed by the DMol3 module of Materials Studio (MS). N, N-dimethylformamide (DMF) was identified as the entrainer, and vapour–liquid equilibrium (VLE) data were measured at atmospheric pressure for the binary system {cyclohexane + cyclohexene} with a temperature range of 354 K to 356 K, the binary system {cyclohexane + DMF} with a temperature range of 354 K to 390 K, and the binary system {cyclohexene + DMF} with a temperature range of 357 K to 421 K. In addition, the thermodynamic consistency of the experimental data was checked using the Wisniak and Van Ness method. The Wilson, NRTL, and UNIQUAC models were used to regress and fit the experimental data to optimize the binary interaction parameters, and the root mean square (RMSD) and average absolute deviation (AAD) values of all models were below 0.01%, indicating that the experimental data provide a basis for the simulation and optimization of the extractive distillation process. [ABSTRACT FROM AUTHOR]

ABSTRACT A method for in situ fabrication of Al@C nanocomposite energetic additives through pulsed discharge in liquid cyclohexane has been proposed. The obtained Al@C nanocomposites consist of large aluminum nanoparticles (over 100 nm) enveloped by fullerenes and a carbon matrix with smaller aluminum particles (under 100 nm) embedded within. DSC–TGA curves indicate that the heat release of Al@C is higher than that of micron‐sized and nano‐sized aluminum particles. Al@C nanocomposites effectively reduce the ignition delay for liquid fuels. The energy efficiency of this method is much higher than that of continuous arc ablation, with a yield of up to 2.5 mg/min. This method allows for the simple, convenient, and safe fabrication of energetic additives, presenting a promising prospect for large‐scale industrial production. [ABSTRACT FROM AUTHOR]

This work exemplifies how incorporating organosilane modifiers into silica matrices allows for tuning the optical response of reflection photonic sensors through customizing the textural properties of hybrid xerogel sensing films. Xerogels with propyl molar percentages 0, 5, and 10% are used to construct photonic probes (OFS0pTEOS, OFS5pTEOS and OFS10pTEOS, respectively) by dip‐coating upon optimizing film deposition parameters. The time response of these probes toward a battery of volatile organic compounds (VOCs) comprising species with different functionality, size‐shape, and polarity is systematically analyzed through ON/OFF experiments, revealing that a low propyl content makes the poor‐responding OFS0pTEOS film highly sensitive toward non‐aromatic, large molecules with low‐polar or non‐polar character in OFS5pTEOS. This sensor is particularly sensitive toward alkanes, with globular cyclohexane (cyHex) outperforming elongated n‐hexane. Variable‐temperature calibration curves obtained from step‐by‐step experiments and adsorption–desorption cycles corroborate these observations and allow hysteresis to be quantified. The response to cyHex closely follows VOC concentration changes with the most stable signal among analytes, leading to well‐defined curves with low‐to‐negligible hysteresis. The isosteric enthalpies of cyHex adsorption are obtained for both the bulk material and the sensor, demonstrating labile adsorbate‐adsorbent interactions ruling the sensor response and becoming more exothermic for larger VOC concentrations. [ABSTRACT FROM AUTHOR]

Raman spectroscopy allows for the unambiguous identification of materials through the inelastic scattering of light. This technique has a great many uses in various aspects of society from academic, scientific, and industry. This paper explores a specific type of Raman spectrometer called a spatial heterodyne Raman spectrometer (SHRSy), which is a variation of an interferometric spectrometer. It utilizes a Michelson interferometer and replaces the mirrors with gratings that transform it from a time-domain spectrometer to a spatial-domain spectrometer, allowing for the entirety of the spectrum to be captured at once. This study specifically tests a half-inch two-grating monolithic SHRS (½-in. 2g-mSHRS), which has a weight of <60 g and a size of 2.2 × 2.2 × 1.3 cm. To do this we excite a variety of organic liquids with a 532 nm neodymium-doped yttrium aluminum garnet (Nd:YAG) pulsed laser, using an excitation energy of 6.5 mJ/pulse and distance of 3 m in conjunction with an intensified charge-coupled device camera. This is the first time that the SHRS has been used for investigating polarized Raman spectra of liquids. We discuss and contrast the instrumental properties such as resolution, spectral range, étendue, and field of view with previously tested mSHRS to give context to the instrument's performance. [ABSTRACT FROM AUTHOR]

Unspecific peroxygenase from Agrocybe aegerite (AaeUPO) is a remarkable catalyst for the oxyfunctionalization of non‐activated C−H bonds under mild conditions. It exhibits comparable activity to P450 monooxygenase but offers the advantage of using H2O2 instead of a complex electron transport chain to reductively activate O2. Here, we demonstrate the successful oxidation of cyclohexane to cyclohexanol/cyclohexanone (KA‐oil) using sol‐gel encapsulated AaeUPO. Remarkably, cyclohexane serves both as a solvent and a substrate in this system, which simplifies product isolation. The ratio of cyclohexanone to cyclohexanol using this approach is remarkably higher compared to the oxidation using free AaeUPO in aqueous media using acetonitrile as a cosolvent. The utilization of sol‐gel encapsulated AaeUPO offers a promising approach for oxyfunctionalization reactions and improves the chances for this enzyme to be incorporated in the same pot with other chemical transformations. [ABSTRACT FROM AUTHOR]

The emerging sub−1 nm nanowires (SNWs) have received tremendous attention given their intriguing properties and broad applications attributable to their ultrasmall feature size. However, applying SNWs in microstructure‐preserving macroscopic functional materials (e.g., aerogels) remains challenging because the solvents used for preparing SNWs are not compatible with conventional supercritical drying or freeze‐drying techniques. In this study, the fabrication of SNW aerogels (SNWAs) is pioneered by developing a nonpolar solvent‐based freeze‐casting strategy. Cyclohexane, a nonpolar solvent with a freezing point (6.5 °C) comparable to that of water, is selected as a reaction and drying medium to assemble various SNWs. The resulting self‐standing SNWAs display low density, excellent hydrophobicity and lipophilicity, and tunable luminescent color. This strategy not only introduces a new aggregation form of SNWs but also provides a creative perspective on synthesizing aerogel structures from sub−1 nm building blocks. [ABSTRACT FROM AUTHOR]

Adjusting the energy levels and fibrillar morphology is paramount to enhancing the power conversion efficiency (PCE) of organic solar cells (OSCs). In the present study, an increase in the open‐circuit voltage (VOC) is facilitated through the elongation of the alkyl chain within AQx (namely AQx‐8), aiming to decrease the free volume ratio (FVR). This reduction in FVR attenuates electron‐phonon coupling, thereby augmenting emission efficiency and diminishing the non‐radiative energy loss (ΔEnr). To further refine the energy levels and morphological characteristics, the external undecyl chain of AQx‐8 is substituted with a shorter carbon chain and cyclohexane noted for its considerable steric hindrance (AQx‐H). This alteration significantly mitigates intermolecular aggregation, expands the bandgap, and elevates the lowest unoccupied molecular orbital (LUMO) energy level, culminating in an elevated VOC of 0.923 V in devices based on AQx‐H. Morphological analysis reveals that blends based on AQx‐H exhibit an enhanced multi‐length‐scale fibrillar structure, which is conducive to exciton dissociation and charge transport, thereby contributing to a high fill factor (FF) nearing 80%. Consequently, this study reports one of the highest binary PCEs documented, standing at 19.5% (with certification at 19.0%). [ABSTRACT FROM AUTHOR]

Commercial NH4-Beta and Na-ZSM-5 zeolites were fluorinated with different amounts of NH4F and using different procedures (room temperature, conventional refluxing, microwave refluxing). Samples were characterized by XRD, N2 physisorption, FTIR, 1H NMR, SEM-EDS, and TGA of adsorbed cyclohexylamine. An increase in the concentration of NH4F led to fluorinated zeolites with higher surface areas and slightly lower amounts of Brønsted acid sites due to some dealumination. Fluorination by conventional or microwave refluxing at shorter times did not dealuminate ZSM-5, resulting in the formation of higher particle sizes. Ni/fluorinated beta catalysts were more active than Ni/fluorinated ZSM-5 catalysts for the hydrodeoxygenation of guaiacol at 180 °C and 15 bar of H2 for 1 h due to their higher amount of acid sites. The appropriate proportion of metallic and Brønsted acid centers allowed for the selective obtention of cyclohexane (58%) for the Ni supported on beta fluorinated with NH4F 0.1 M catalyst. The combination of this fluorinated beta to a Ni/ordered mesoporous carbon catalyst significantly boosted its selectivity to cyclohexane from 0 to 65%. Fluorinated ZSM-5 samples, although having stronger Brønsted acid sites, as observed by 1H NMR, they had lower amounts, leading to higher selectivity to cyclohexanol when used as catalytic supports. [ABSTRACT FROM AUTHOR]

We calculate the phase diagrams and predict the temperature dependence of the thermodynamic quantities at high pressures for the solid – liquid and solid – solid transitions in n-paraffins. This calculation is performed by fitting the phase line equations as obtainedfrom the Landau model to the experimental data from the literature. On thebasis of the Landau model, phase diagram of the solid – solid transition ispredicted at 0.1 MPa for the binary mixtures of n-tridecane + (n-hexane and cyclohexane).For the calculation of the heat capacity the extended mean field is employedfor the n-paraffins studied here. We find that our calculated phase diagrams explain the observed behaviour of the liquid – solid transitions at high pressures in those binary mixtures. Our phase diagrams predicted at 0.1 MPa and our predictions for the thermodynamic quantities can be compared with the experiments for those binary mixtures. [ABSTRACT FROM AUTHOR]

To promote the application of lignin in Pickering emulsions, the influences of six lignin particles with different hydrophobicity on the emulsifying and stabilizing performances for oil phases with different polarity to form oil in water Pickering emulsions were investigated. The results showed that the best emulsification performance was achieved when the three-phase (oil–water–lignin particle) contact angle was close to 90°. Alkyl-bridged lignin particles with stronger hydrophobicity have a better emulsification effect on cyclohexane with less polarity, while carboxymethylated lignin particles with stronger hydrophilicity have better emulsification effect on n-heptanol with higher polarity. Furthermore, the stability of Pickering emulsions can be improved by appropriately increasing the surface charge and decreasing the particular size of the lignin particles. [ABSTRACT FROM AUTHOR]

The effect of crown ethers and polyglycols on the liquid-phase oxidation of cyclohexane and alkylaromatic hydrocarbons (toluene and p-xylene) with molecular oxygen catalyzed by transition metal salts has been investigated. It has been determined that crown ethers increase the reaction rate at both low and high conversion levels of cyclohexane and alkylaromatic hydrocarbons. The additives under study primarily affect the selectivity of the oxidation products. Crown ether and polyglycol additives to cobalt naphthenate increase the cyclohexanone to cyclohexanol molar ratio in cyclohexane oxidation. The crown ether additives to cobalt acetate increase the selectivity for alcohol in the initial stage of toluene and p-xylene oxidation. At higher alkylarene conversion, the additives enhance the selectivity for carboxylic acids. We assume that crown ethers and polyglycols form complexes with transition metal ions, changing the redox potential of the ions. This change in redox potential affects both the reaction rate and the selectivity of the oxidation products. The study concludes that crown ether and polyglycol additives influence the stages of the catalytic liquid-phase oxidation of hydrocarbons. [ABSTRACT FROM AUTHOR]

This article discusses the use of perfluorinated sulfamides in various technological processes. The potential of aminotoxane as a catalyst in the cyclohexane oxidation process was studied. The use of aminotoxane significantly shifts the distribution of target products in cyclohexane oxidation, favoring increased alcohol formation. This catalytic system is distinct from those involving crown ethers and polyglycols, suggesting a specific mechanism of influence by perfluorinated sulfamides on the intermediate stages of radical-chain oxidation. For the by-product adipic acid, which is formed in significant amounts, a complex method of utilizing cyclohexane oxidation products is proposed. Specifically, esterification of adipic acid with alcohol was performed, resulting in the production of dibutyl adipinate, a valuable raw material for plasticizer manufacturing. The yield of dibutyl adipinate was 57.6%. The study found that cyclohexane oxidation in the presence of a binary catalyst, cobalt naphthenate–aminotoxane, results in an increased oxidation rate, a threefold reduction in ester and acid selectivity, and a twofold increase in cyclohexanol selectivity compared to oxidation with cobalt naphthenate alone. [ABSTRACT FROM AUTHOR]

Decatungstate ((nBu4N)4W10O32, marked as DTs) and PMo12-nVn could be easily synthesized via polymerization in acidic aqueous solution. They can efficiently catalyze the oxidation of cyclohexane to afford cyclohexanone and cyclohexanol under visible light, affording about 30% conversion in the presence of additive HCl. This is the first example to show the influence of HCl on oxidizing capacity for DTs and PMo12-nVn. It was found that PMo12-nVn could induce the generation of chlorine radical in the presence of HCl, playing a significant role to realize the oxidation of cyclohexane. [ABSTRACT FROM AUTHOR]

Decatungstate ((nBu4N)4W10O32, marked as DTs) and PMo12-nVn could be easily synthesized via polymerization in acidic aqueous solution. They can efficiently catalyze the oxidation of cyclohexane to afford cyclohexanone and cyclohexanol under visible light, affording about 30% conversion in the presence of additive HCl. This is the first example to show the influence of HCl on oxidizing capacity for DTs and PMo12-nVn. It was found that PMo12-nVn could induce the generation of chlorine radical in the presence of HCl, playing a significant role to realize the oxidation of cyclohexane. [ABSTRACT FROM AUTHOR]

The present work contributes to the development of the shadowgraph method for its routine application for an accurate determination of the Fick diffusion coefficient D11 of binary fluid mixtures. In this context, measurement and data evaluation strategies for thermodiffusion experiments where confinement and advection are potentially present are elaborated by studying two binary liquid mixtures with positive and negative Soret coefficients, i.e., 1,2,3,4-tetrahydronaphthalene/n-dodecane and acetone/cyclohexane. For obtaining accurate D11 data, the dynamics of non-equilibrium fluctuations in concentration is analyzed considering recent theory by data evaluation procedures that are demonstrated to be suitable for different experimental configurations. [ABSTRACT FROM AUTHOR]

The electrochemical stereoselective dehydrogenative homocoupling of β‐naphthylamine derivatives was investigated and successfully accomplished, the chiral diaryl amines being obtained in up to 60 % yield. The use of an enantiopure β‐naphthylamine featuring an aminoalcohol as chiral auxiliary led to the expected 2,2'‐binaphthyl diamine derivative in up to 96/4 diastereoisomeric ratio. The application of the methodology to the intramolecular cross coupling of the enantiopure bis‐N‐β‐naphthylamine 1,2‐trans‐diamino cyclohexane led to the formation of a single enantiopure diastereoisomer in 37 % yield. [ABSTRACT FROM AUTHOR]

In the present study, bio-based polymeric blends have been prepared for applications in the field of sustainable food packaging, starting from two furan-based homopolymers, poly(hexamethylene 2,5-furanoate) (PHF) and poly(pentamethylene 2,5-furanoate) (PPeF). PHF and PPeF were synthesized by two-step melt polycondensation—a solvent-free synthetic strategy—and then binary physical mixtures, PHF/PPeF, with different weight compositions were prepared by dissolution in a common solvent. The blends were processed into compression-moulded films, and molecular, morphological, structural, thermal, and mechanical characterizations were subsequently carried out. Blending did not negatively affect the thermal stability of the parent homopolymers, and good compatibility between them was observed. This strategy also allowed for the modulation of the chain rigidity as well as of the crystallinity, simply by acting on the relative weight amount of the homopolymers. From a mechanical point of view, the presence of PPeF led to a reduction in stiffness and an increase in the elongation at break, obtaining materials with an elastomeric behaviour. Evaluation of the gas barrier properties confirmed that the good barrier properties of PHF were preserved by blending. Finally, lab-scale composting tests confirmed a greater weight loss of the mixtures with respect to the PHF homopolymer. [ABSTRACT FROM AUTHOR]

C–H bond activation under mild conditions remains a great challenge in the chemical industry, while catalytic cyclohexane oxidation is inefficient and often requires organic solvents and strong oxidants. This study constructed a C3N4/WO3 Z-type heterojunction catalyst to efficiently convert cyclohexane into cyclohexanone and cyclohexanol (KA oil) through aqueous phase oxidation by O2 under visible light irradiation. With strong redox performance and high photogenerated carrier separation ability, the proposed composite catalyst can produce the key active species for cyclohexane oxidation in the H2O–O2 system. The reaction mechanism was clarified through experiment and DFT theory calculation. Cyclohexane was converted into cyclohexyl radical under the action of ·OH, and ·O2− converted most products into cyclohexanone. The catalyst can be recycled under optimized process conditions while reaching a KA oil yield of 139.73 μmol g−1 h−1 and a selectivity of 93.1%. [ABSTRACT FROM AUTHOR]

The density, viscosity and sound velocity of the binary liquid mixtures of P-methyl acetophenone with cyclohexylamine, cyclohexanol, and cyclohexane are measured over the complete composition range at temperatures of 303.15–313.15 K and at atmospheric pressure of 0.1 M. Excess molar volume, excess isentropic compressibility and viscosity deviation are calculated from the experimental measurements. The sign and magnitude of the derived parameters reveal the nature and type of interactions between the constituent molecules in the binary mixtures. Thermodynamic properties for this work reveal association interactions between dissimilar molecules in the binary systems P-methyl acetophenone + cyclohexylamine and P-methyl acetophenone + cyclohexanol systems, whereas dispersion forces cause the opposite trend in the other binary system P-methyl acetophenone + cyclohexane. [ABSTRACT FROM AUTHOR]

The present work reports experimental data on the thermal conductivity of the four hydrocarbons cyclohexane, n-decane, n-hexadecane, and squalane in the liquid state at ambient pressure up to temperatures of 353.15 K. Absolute measurements were performed with a steady-state guarded parallel-plate instrument (GPPI) with an average expanded (coverage factor k = 2) measurement uncertainty of 2 %. For the linear alkanes n-decane and n-hexadecane as well as the cyclic compound cyclohexane, the measured thermal conductivities agree with reference correlations in the literature, indicating the reliability of the technique used for the study of fluids with relatively low thermal conductivities and weak absorption of radiation. For the first time, experimental data are determined for the long-branched alkane squalane between (278 and 353) K, which cannot be accurately represented with estimation methods commonly used in the literature. In summary, the present measurement results confirm the existing database for representative linear and cyclic hydrocarbons and provide first experimental thermal conductivities for squalane. [ABSTRACT FROM AUTHOR]

Swelling experiments are conducted on nonfiller natural rubber using four solvents (toluene, cyclohexane, tetrahydrofuran (THF), and methylethylketone (MEK)) over temperatures from 10 to 70 °C. Toluene, cyclohexane, and THF, classified as effective solvents, show swelling ratios between 3 and 7, influenced by the crosslink density of the rubber. MEK, however, has a lower ratio of 1.5 to 2. Temperature has a minor impact on swelling compared to the crosslink density. The study evaluates the Extended Modified Double Lattice (EMDL) model for its mixing contribution in polymer network swelling, aiming to improve the Flory–Hüggins (FH) model. The superiority of EMDL above FH is in the boundary condition at the unvulcanized state, the former aligning its interaction energy with values from solvent activities in primary linear polymer/solvent solutions, unlike the FH model. The EMDL model also accounts for oriented interactions in polar solvents through a secondary lattice, linking specific interaction energy with solvent dipole moments. The study observes a nonlinear correlation between crosslinking density and sulfur amount, proposing a nonrandom mixing at lower sulfur concentrations. This model shows strong alignment with experimental data, suggesting that replacing the FH model's mixing contribution with the EMDL model could improve results with minimal additional complexity. [ABSTRACT FROM AUTHOR]

In this work the distribution coefficients (D) of polonium between 0.1 mol dm−3 TOPO/toluene; TOPO/cyclohexane; TBP/toluene and TBP/cyclohexane and aqueous solutions of inorganic acids (HCl, HNO3, H2SO4 and H3PO4) were determinated. The molarities of inorganic acids were between 0.5 and 12.0 mol dm−3. The activity of extracted Po-209 was measured by means of liquid scintillation counting. The best result was obtained for TOPO/toluene and 2 mol dm−3 H2SO4 system (D = 62 ± 9). The most stable conditions of extraction were found for TOPO/toluene-HCl system. [ABSTRACT FROM AUTHOR]

Furan semi-aromatic polyamides have become a biobased substitute for existing petrochemical semi-aromatic polyamides and received more and more attention. In this study, a series of high-performance biobased furan polyamides with different diamine chain lengths (Poly(butylene furanamide) (PA4F), Poly(pentylene furanamide) (PA5F), Poly(hexamethylene furanamide) (PA6F), Poly(octamethylene furanamide) (PA8F) and Poly(dodecamethylene furanamide) (PA12F)) were successfully prepared; Except for PA4F, other resins could be synthesized by one step bulk polymerization. Meanwhile, the effect of diamine chain length was studied. Except for PA4F they were amorphous which was confirmed by IR, XRD and DSC analysis. PA12F to PA5F had high weight-average molecular weights (Mw) ranging from 34,000 to 65,500 g/mol, number-average molecular weight (Mn) ranging from 6100 to 26,300 g/mol, glass transition temperature (Tg) ranging from 89 to 138 ℃ and temperature of decomposition at 5% mass loss (Td-5%) from 357 to 408 ℃. The Tg of PA4F reached as high as 142 ℃. The tensile strength of PA12F, PA8F and PA5F was obtained for the first time, and reached up to 45, 62 and 84 MPa, respectively. The tensile strength of PA6F was also high at 74 MPa. The α relaxation temperatures of PA12F to PA5F were also high, up to 107, 136, 146 and 158 ℃, respectively. [ABSTRACT FROM AUTHOR]

Naphthenic acids (NA) are organic compounds commonly found in crude oil and produced water, known for their recalcitrance and toxicity. This study introduces a new adsorbent, a polymer derived from spent coffee grounds (SCGs), through a straightforward cross-linking method for removing cyclohexane carboxylic acid as representative NA. The adsorption kinetics followed a pseudo-second-order model for the data (0.007 g min−1 mg−1), while the equilibrium data fitted the Sips model ( q m = 140.55 mg g−1). The process's thermodynamics indicated that the target NA's adsorption was spontaneous and exothermic. The localized sterical and energetic aspects were investigated through statistical physical modeling, which corroborated that the adsorption occurred indeed in monolayer, as suggested by the Sips model, but revealed the contribution of two energies per site ( n 1 ; n 2 ). The number of molecules adsorbed per site (n ) was highly influenced by the temperature as n 1 decreased with increasing temperature and n 2 increased. These results were experimentally demonstrated within the pH range between 4 and 6, where both C6H11COO−(aq.) and C6H11COOH(aq.) species coexisted and were adsorbed by different energy sites. The polymer produced was naturally porous and amorphous, with a low surface area of 20 to 30 m2 g−1 that presented more energetically accessible sites than other adsorbents with much higher surface areas. Thus, this study shows that the relation between surface area and high adsorption efficiency depends on the compatibility between the energetic states of the receptor sites, the speciation of the adsorbate molecules, and the temperature range studied. [ABSTRACT FROM AUTHOR]

This study explores the anharmonic local mode vibrational frequencies of the cyclohexane (C6H12) molecule, classified under the D3d point group, up to the second overtone. We use a vibrational Hamiltonian model based on U(2) Lie algebras. Our Lie algebraic method is characterized by integrating minimized algebraic parameters precisely adapted for cyclohexane. This process involves substituting each bond in the molecule with a corresponding Lie algebra, leading to the development of a Hamiltonian that includes interacting operators. Through this detailed analysis, we illuminate the anharmonic vibrational behavior of cyclohexane, providing significant insights into its molecular dynamics within a framework that respects symmetry adaptation. [ABSTRACT FROM AUTHOR]

Studying the fates of oil components and their interactions with ecological systems is essential for developing comprehensive management strategies and enhancing restoration following oil spill incidents. The potential expansion of Kazakhstan's role in the global oil market necessitates the existence of land-specific studies that contribute to the field of bioremediation. In this study, a set of experiments was designed to assess the growth and biodegradation capacities of eight fungal strains sourced from Kazakhstan soil when exposed to the hydrocarbon substrates from which they were initially isolated. The strains were identified as Aspergillus sp. SBUG-M1743, Penicillium javanicum SBUG-M1744, SBUG-M1770, Trichoderma harzianum SBUG-M1750 and Fusarium oxysporum SBUG-1746, SBUG-M1748, SBUG-M1768 and SBUG-M1769 using the internal transcribed spacer (ITS) region. Furthermore, microscopic and macroscopic evaluations agreed with the sequence-based identification. Aspergillus sp. SBUG-M1743 and P. javanicum SBUG-M1744 displayed remarkable biodegradation capabilities in the presence of tetradecane with up to a 9-fold biomass increase in the static cultures. T. harzianum SBUG-M1750 exhibited poor growth, which was a consequence of its low efficiency of tetradecane degradation. Monocarboxylic acids were the main degradation products by SBUG-M1743, SBUG-M1744, SBUG-M1750, and SBUG-M1770 indicating the monoterminal degradation pathway through β-oxidation, while the additional detection of dicarboxylic acid in SBUG-M1768 and SBUG-M1769 cultures was indicative of the fungus' ability to undertake both monoterminal and diterminal degradation pathways. F. oxysporum SBUG-M1746 and SBUG-M1748 in the presence of cyclohexanone showed a doubling of the biomass with the ability to degrade the substrate almost completely in shake cultures. F. oxysporum SBUG-M1746 was also able to degrade cyclohexane completely and excreted all possible metabolites of the degradation pathway. Understanding the degradation potential of these fungal isolates to different hydrocarbon substrates will help in developing effective bioremediation strategies tailored to local conditions. [ABSTRACT FROM AUTHOR]

Pickering emulsion stabilized by lignin particles has many advantages such as high flexibility, natural non-toxicity, anti-oxidation, and anti-ultraviolet. In order to promote the application of industrial lignin in the field of Pickering emulsions, this study has done comparatively systematic and basic research on Pickering emulsions stabilized by lignin particles. The emulsification effects of lignin particles on cyclohexane and n-decanol which have opposite polarity were compared firstly under different oil-water ratios. It was found that stable emulsions formed when the three-phase contact angle of oil/water/lignin was closer to 90°. The weakly polar cyclohexane could be well-emulsified by lignin particles, while the strong polar n-decanol could not. Cyclohexane was used as the oil phase to discuss the emulsification ability of lignin particles under different concentrations or with different particle sizes. The results show increasing the concentration of lignin particles or reducing the particle size can improve the emulsification performance. [ABSTRACT FROM AUTHOR]

Abstract Unspecific peroxygenase from Agrocybe aegerite (AaeUPO) is a remarkable catalyst for the oxyfunctionalization of non‐activated C−H bonds under mild conditions. It exhibits comparable activity to P450 monooxygenase but offers the advantage of using H2O2 instead of a complex electron transport chain to reductively activate O2. Here, we demonstrate the successful oxidation of cyclohexane to cyclohexanol/cyclohexanone (KA‐oil) using sol‐gel encapsulated AaeUPO. Remarkably, cyclohexane serves both as a solvent and a substrate in this system, which simplifies product isolation. The ratio of cyclohexanone to cyclohexanol using this approach is remarkably higher compared to the oxidation using free AaeUPO in aqueous media using acetonitrile as a cosolvent. The utilization of sol‐gel encapsulated AaeUPO offers a promising approach for oxyfunctionalization reactions and improves the chances for this enzyme to be incorporated in the same pot with other chemical transformations.

Superhydrophobic and superhydrophilic surfaces are attracting significant attention in fundamental and applied research. This study fabricated the micro/nanostructure with a Q-switched nanosecond pulsed laser on the Ti-6Al-4V surface. Three laser-generated surface topographies on titanium were produced based on three different pitch sizes (51 μm, 34 μm, and 29 μm). The laser textured surfaces (LTS) were studied in terms of both structure evolution and chemical composition using Field Emission Scanning Electron Microscopy (FE-SEM), Optical Microscopy (OM), Confocal Laser Scanning Microscopy (CLSM), Raman Spectroscopy, and X-ray Diffractometer (XRD). 29 μm pitch displayed the lowest water contact angle of 18.5° and surface roughness of 0.5 μm. This structure was further treated with cyclohexane at different temperatures. The best sample reached superhydrophobicity with a maximum water contact angle of 155.1° immediately after being treated with cyclohexane at the low temperature of 70 °C for 2 h, while the raw surface, for comparison, showed no change in hydrophobicity after being treated with cyclohexane under the same condition. Thus showing clear evidence of a combined effect between LTS and post-treatment. The surface features were assessed to explain the underlying process.

Highly efficient and low-cost bio-oil upgrading process is critical for the realization of renewable biomass as the substitution for fossil oil in the production of biofuel. In this study, a highly dispersed Co/SiO2–Al2O3 catalysts were prepared by simple wet impregnation, and its catalytical activity in the hydrodeoxygenation of guaiacol, one of the most key reactions of bio-oil upgrading, was evaluated. The as-prepared catalyst could provide a full conversion of guaiacol (100%) and 96.8% selectivity of cyclohexane under relatively mild conditions (250 °C, 2-MPa H2, 1 h). The characterizations of the as-prepared Co/SiO2–Al2O3 catalyst confirmed a highly dispersed Co particle with the SiO2–Al2O3 support, which favored the selectivity of cyclohexane. In addition, both the synergy of Co0 and Coδ+ species and the medium-strength acidic sites contributed to the high catalytical performance of the catalyst. According to the distribution of the products, the reaction path from guaiacol to cyclohexane was speculated. Furthermore, the Co/SiO2–Al2O3 catalyst also possessed high stability and versatility. The above properties together with the easy preparation method entitled the Co/SiO2–Al2O3 catalyst great potential as a non-noble metal catalyst for the scale-up applications in bio-oil upgrading process. [ABSTRACT FROM AUTHOR]

Coordination cages have been widely reported to bind a variety of guests, which are useful for chemical separation. Although the use of cages in the solid state benefits the recycling, the flexibility, dynamicity, and metal-ligand bond reversibility of solid-state cages are poor, preventing efficient guest encapsulation. Here we report a type of coordination cage-integrated solid materials that can be swelled into gel in water. The material is prepared through incorporation of an anionic FeII4L6 cage as the counterion of a cationic poly(ionic liquid) (MOC@PIL). The immobilized cages within MOC@PILs have been found to greatly affect the swelling ability of MOC@PILs and thus the mechanical properties. Importantly, upon swelling, the uptake of water provides an ideal microenvironment within the gels for the immobilized cages to dynamically move and flex that leads to excellent solution-level guest binding performances. This concept has enabled the use of MOC@PILs as efficient adsorbents for the removal of pollutants from water and for the purification of toluene and cyclohexane. Importantly, MOC@PILs can be regenerated through a deswelling strategy along with the recycling of the extracted guests. The efficient encapsulation of guests by coordination cages in the solid state is prevented by their flexibility, dynamicity, and metal-ligand bond reversibility. Here, the authors report coordination cages integrated into poly(ionic liquid)s to control swelling and mechanical properties of the gels and develop efficient and regenerable supramolecular separation materials. [ABSTRACT FROM AUTHOR]

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Ordered hexagonal mesoporous aluminophosphate and its cobalt‐substituted analogue were successfully synthesized using ionic liquid as a structure‐directing agent. The resulting materials were systematically characterized by various analytical, spectroscopic, and imaging methods, confirming the presence of divalent cobalt in the tetrahedral framework of the matrix. Further, the high surface area, pore volume, and thicker mesopore walls of these materials impart good thermal and hydrothermal stability. The mesoporous catalysts showed excellent activity towards the oxidation of cyclohexane reactions using hydrogen peroxide as an oxidant, with 98.5 % conversion and 90.4 % selectivity towards cyclohexanol. [ABSTRACT FROM AUTHOR]

The oxidation of cycloalkanes is important in the combustion of transportation fuels and in atmospheric secondary organic aerosol formation. A transient carbon-centered radical intermediate (•QOOH) in the oxidation of cyclohexane is identified through its infrared fingerprint and time-and energy-resolved unimolecular dissociation dynamics to hydroxyl (OH) radical and bicyclic ether products. Although the cyclohexyl ring structure leads to three nearly degenerate •QOOH isomers (β-, γ-, and δ-QOOH), their transition state (TS) barriers to OH products are predicted to differ considerably. Selective characterization of the β-QOOH isomer is achieved at excitation energies associated with the lowest TS barrier, resulting in rapid unimolecular decay to OH products that are detected. A benchmarking approach is employed for the calculation of high-accuracy stationary point energies, in particular TS barriers, for cyclohexane oxidation (C6H11O2), building on higher-level reference calculations for the smaller ethane oxidation (C2H5O2) system. The isomer-specific characterization of β-QOOH is validated by comparison of experimental OH product appearance rates with computed statistical microcanonical rates, including significant heavy-atom tunneling, at energies in the vicinity of the TS barrier. Master-equation modeling is utilized to extend the results to thermal unimolecular decay rate constants at temperatures and pressures relevant to cyclohexane combustion. [ABSTRACT FROM AUTHOR]

Among the numerous polymers synthesised to date, polyurethane is one of the most promising polymers in terms of diversity and scale of practical application. Polymers of this class are characterised by unique physico-mechanical and dielectric properties and have universal application in various fields of mechanical engineering and agriculture. Their scope of application is limited by the limited range of monomers necessary for their synthesis, relatively low thermal and heat resistance and poor solubility in organic solvents, which makes it difficult to process them from solutions. Therefore, polyurethanes, which are characterised by both good solubility in conventional organic solvents and high heat and heat resistance, are of particular importance. In the presented work, the synthesis of new types of primary diols containing card groups with different structures and a new linear homogeneous card polyurethane based on them was processed and implemented for the first time, their properties and the basic laws of the polymer formation reaction were studied. [ABSTRACT FROM AUTHOR]

A systematic study of the hydrogenation of individual aromatic hydrocarbons (benzene, toluene, xylene) and their mixtures was carried out at 1800C, H2/Ar=7, WHSV = 2h-1 and atmospheric pressure on a composite catalyst 0.4%Co/HZSM-5/SO4 2-(2.0%)-ZrO2. It has been established that the developed catalyst has a high hydrogenating ability with respect to aromatic hydrocarbons at low hydrogen pressures. Alkyl-substituted benzenes turned out to be more active. It was found that alkyl substituents increase the activity of hydrogenation of the benzene ring of an aromatic hydrocarbon. According to their conversion, benzene, toluene and xylene form the following sequence: benzene

Metal–organic frameworks with complex geometry have garnered significant attention in technological fields due to their diverse properties. Multimetallic metal‐organic frameworks (MOFs) have potential to demonstrate superior conductivity and efficiency compared to pristines, but, they have not been explored to research on large scale. Herein, significant effect of binary (NiCo‐) and ternary (NiCoMn‐) MOFs is explored with a novel approach using an organic ligand hexamethylene tetra‐amine (HMT). The as‐synthesized MOFs with their distinctive structures are thoroughly examined to analyze their structural, morphological, and electrochemical properties. In a standard half‐cell setup, the electrochemical behaviors of both samples are investigated, as both electrodes exhibit specific capacities of 349 and 905 C g−1, at 3 mV s−1, individually. Due to promising electrochemical responses of NiCoMnMOF, a supercapattery device is constructed as NiCoMnMOF//AC. This hybridization leads to the remarkable specific energy (78 Wh kg−1) and specific power (3500 W kg−1) with stability rate of ≈96% and Coulombic efficiency of 99% after undergoing 5000 galvanostatic charge–discharge cycles, making it highly suitable for modern applications. To gain better insight of supercapattery device, a semiempirical approach is employed, using Dunn's modulation. Thus, the synergy of NiCoMnMOF//AC in the single hybrid device exhibiting battery‐like characteristics holds tremendous potential for driving innovations in energy storage technology. [ABSTRACT FROM AUTHOR]

Due to the growing demand for energy, there is a need to find sources of additional types of fuel. A possible solution to this problem is the use of mixtures of diesel fuel with light gas oil, which requires compliance with cetane number standards. The process of ring opening of cyclic hydrocarbons seems promising for solving this problem. In this work, rhodium-based catalysts with zirconium supports doped with additives of other oxides that stabilize the surface of zirconia (SiO2, TiO2, WO3,Y2O3, La2O3) are synthesized and characterized by nitrogen low-temperature adsorption-desorption, X-ray phase analysis, energy dispersive scanning electron microscopy, and diffuse reflectance IR spectroscopy with CD3CN as a test molecule, and catalytic studies are carried out in the reaction of cyclohexane ring opening. Catalyst Rh/ZrO2-TiO2 is most selective for n-hexane (77%) at a temperature of 300°C. Rh/ZrO2-SiO2 has the greatest productivity for n‑hexane: the achieved yield is 6.6 mmoln-hexane g h−1. [ABSTRACT FROM AUTHOR]

Producing aromatic compounds sustainably from renewable sources is essential to reduce reliance on fossil fuels. This study aims to elucidate the multifunctional behavior of Ir on Pt‐HZSM5, and their influence on the catalytic activity of n‐pentane isomerization, cyclohexane ring opening, and cumene cracking. The results showed that Ir created another active and Lewis's acid site, which increased the acid sites (H+), thus enhancing the catalytic performance of Pt‐HZSM5. Moreover, Ir inhibited the atomic hydrogen bonding interaction and hence improved the main reaction and suppressed the side reaction. Therefore, the mechanism of the main reaction over Ir/Pt‐HZSM5 can be described as the following steps: (i) Interaction of reactant with H+; (ii) Reaction of carbenium ion intermediate; and (iii) Interaction of a carbenium ion intermediate with H−, followed by desorption. This study provides a comprehensive understanding of the intricate catalytic pathways, offering insights into the design of efficient multifunctional catalysts for various petrochemical applications. [ABSTRACT FROM AUTHOR]

Two series of biobased poly(ether‐ester)s comprised of poly(hexamethylene 2,5‐furandicarboxylate) (PHF) as the rigid segments and biopolytetrahydrofuran (pTHF) with different molecular masses (1000 and 2000 g/mol) as the flexible segments were synthesized employing polycondensation in the molten state. The study mainly focuses on comparing these two series in terms of the length of the flexible segment. The content of pTHF segments in the copolymer chains varied from 25 to 75 wt.%. The molecular structure and composition, phase structure, and thermal and mechanical properties were characterized by nuclear magnetic resonance (1H NMR) and Fourier‐transformed infrared (FTIR) spectroscopies, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and positron annihilation lifetime spectroscopy (PALS). In addition, mechanical performance and thermo‐oxidative and thermal stability have been investigated. Moreover, cyclic tensile properties were studied to evaluate the elastic properties. 1H NMR and FTIR spectroscopies demonstrate that the syntheses were correctly carried out, which made it possible to obtain the desired compositions of the block copolymers with high molecular masses. The decrease in Tm1, Tc1, and XcPHF values was visible, along with the increase in the flexible segment content. Moreover, the characteristic properties measured by PALS and the values of temperatures designated from TGA (inert and oxidizing atmosphere) did not vary between copolymer series PHF‐b‐F‐pTHF1000 and PHF‐b‐F‐pTHF2000. In turn, along with an increase in flexible segment content and the length of the pTHF, the values of tensile modulus, stress at break, and hardness decrease, while the value of elongation at break increases. [ABSTRACT FROM AUTHOR]

A lot of research is constantly underway in the world to develop new or improve the current processes of the chemical industry to make them more effective and environmentally friendly. The described research on the oxidation of cyclohexane or cyclohexanone to adipic acid with a coupled action of UV radiation and oxygen–ozone mixture, instead of the currently used oxidation with HNO3, is part of this trend. Gas chromatography was used to determine process indicators, such as cyclohexane conversion and selectivity to AA, which exceeded 50% at 25 oC, after 16 h. This method can also be used for the preparation of other dicarboxylic acids from cycloalkanes, which proves its universal character. [ABSTRACT FROM AUTHOR]

In order to protect the marine environment, traditional marine antifouling coatings such as tributyltin (TBT)‐based antifouling coatings have been phased out. There is an urgent need to develop environmentally friendly marine antifouling coatings. In this work, the antibacterial poly(hexamethylene guanidine) (PHMG) was introduced into polyurethane (PU) through chemical bond to prepare a green environmentally friendly marine antifouling coating (PU‐PHMG). The morphology, antimicrobial properties, mechanical properties and thermostability of the PU‐PHMG films were investigated. The antimicrobial rates of PU‐PHMG films against E. coli and S. aureus were both more than 99.9% when PHMG content in the films reached 1.0 wt%. The excellent antimicrobial activities can be maintained for more than 90 days due to the non‐leaching characteristic of PHMG. The growth of algae was also inhibited on the surface of PU‐PHMG films. The PU‐PHMG coating is promising for the applications in marine antifouling field. [ABSTRACT FROM AUTHOR]

Self-diffusion in a cyclohexane–methanol binary system was studied by the pulsed gradient spin-echo 1H NMR method at temperatures of 298 (in the region of limited miscibility) and 323 K (over entire composition of the mixed solvent). According to the data obtained, the concentration dependences of the self-diffusion coefficients of cyclohexane increase with methanol concentration. However, the concentration dependences of the self-diffusion coefficients of methanol have minima. At the same time, according to 1H NMR data, the chemical shift of OH protons in the methanol molecule decrease with increasing cyclohexane concentration and temperature, which indicates a decrease in the degree of methanol self-association in the system. The effect of molecular association on methanol self-diffusion in the binary system was evaluated using the Stokes–Einstein equation. The concentration dependences of the relative effective hydrodynamic radius of methanol were shown to have maxima. [ABSTRACT FROM AUTHOR]

Objectives. To investigate the regularities of the process of joint production of epoxycyclohexane, cyclohexanol, and cyclohexanone using the cyclohexene epoxidation reaction with cyclohexyl hydroperoxide in the presence of an ammonium paramolybdate catalyst, representing an alternative to the method of cyclohexanol and cyclohexanone synthesis by alkaline catalytic decomposition of cyclohexyl hydroperoxide.Methods. The qualitative and quantitative analysis of the obtained intermediate and target compounds was determined using modern physicochemical research methods: gas–liquid chromatography using the Chromatec-Crystal 5000.2 hardware and software complex with a flame ionization detector and infrared spectroscopy on an RX-1 infrared Fourier spectrometer. The content of hydroperoxide in the oxidation products was determined using iodometric titration, while the carboxylic acid content was determined by the titrimetric method based on the neutralization reaction.Results. The presented method for obtaining cyclohexanol and cyclohexanone together with epoxycyclohexane by the reaction of cyclohexene epoxidation with cyclohexyl hydroperoxide containing cyclohexane in the products of high-temperature liquid-phase oxidation is experimentally substantiated. The influence of various technological parameters on the process of liquid-phase oxidation of cyclohexane to hydroperoxide is described. The conditions for carrying out this reaction are determined to ensure the achievement of a content of cyclohexyl hydroperoxide of 1.5 wt % in the products of oxidation. The regularities of the epoxidation reaction of the synthesized cyclohexyl hydroperoxide with cyclohexene in the presence of an ammonium paramolybdate catalyst are analyzed.Conclusions. Epoxidation of cyclohexene with cyclohexyl hydroperoxide produced epoxycyclohexane at a yield of 80–90% and a conversion of cyclohexane hydroperoxide of 85%.

Commercial NH4-Beta and Na-ZSM-5 zeolites were fluorinated with different amounts of NH4F and using different procedures (room temperature, conventional refluxing, microwave refluxing). Samples were characterized by XRD, N2 physisorption, FTIR, 1H NMR, SEM-EDS, and TGA of adsorbed cyclohexylamine. An increase in the concentration of NH4F led to fluorinated zeolites with higher surface areas and slightly lower amounts of Brønsted acid sites due to some dealumination. Fluorination by conventional or microwave refluxing at shorter times did not dealuminate ZSM-5, resulting in the formation of higher particle sizes. Ni/fluorinated beta catalysts were more active than Ni/fluorinated ZSM-5 catalysts for the hydrodeoxygenation of guaiacol at 180 °C and 15 bar of H2 for 1 h due to their higher amount of acid sites. The appropriate proportion of metallic and Brønsted acid centers allowed for the selective obtention of cyclohexane (58%) for the Ni supported on beta fluorinated with NH4F 0.1 M catalyst. The combination of this fluorinated beta to a Ni/ordered mesoporous carbon catalyst significantly boosted its selectivity to cyclohexane from 0 to 65%. Fluorinated ZSM-5 samples, although having stronger Brønsted acid sites, as observed by 1H NMR, they had lower amounts, leading to higher selectivity to cyclohexanol when used as catalytic supports.

The combination of macrocyclic chemistry with co-crystal engineering has promoted the development of materials with vapochromic behaviors in supramolecular science. Herein, we develop a macrocycle co-crystal based on hybrid[4]arene and 1,2,4,5-tetracyanobenzene that is able to construct vapochromic materials. After the capture of benzene and toluene vapors, activated hybrid[4]arene-based co-crystal forms new structures, accompanied by color changes from brown to yellow. However, when hybrid[4]arene-based co-crystal captures cyclohexane and pyridine, neither structures nor colors change. Interestingly, hybrid[4]arene-based co-crystal can separate benzene from a benzene/cyclohexane equal-volume mixture and allow toluene to be removed from a toluene/ pyridine equal-volume mixture with purities reaching 100%. In addition, the process of adsorptive separation can be visually monitored. The selectivity of benzene from a benzene/cyclohexane equal-volume mixture and toluene from a toluene/ pyridine equal-volume mixture is attributed to the different changes in the charge-transfer interaction between hybrid[4]arene and 1,2,4,5-tetracyanobenzene when hybrid[4]arene-based co-crystal captures different vapors. Moreover, hybrid[4]arene-based co-crystal can be reused without losing selectivity and performance. This work constructs a vapochromic material for hydrocarbon separation. Cocrystal engineering combined with macrocycle chemistry has allowed the development of materials with vapochromic characteristics. Here, the authors report the development of a macrocycle cocrystal for the separation of trace solvents. [ABSTRACT FROM AUTHOR]

Infection prevention and public health are a vital concern worldwide, especially during pandemics such as COVID-19 and seasonal influenza. Frequent manual disinfection and use of chemical spray coatings at public facilities are the typical measures taken to protect people from coronaviruses and other pathogens. However, limitations of human resources and coating durability, as well as the safety of disinfectants used are the major concerns in society during a pandemic. Non-leachable antimicrobial agent poly(hexamethylene biguanide) (PHMB) was mixed into photocurable liquid resins to produce novel and tailor-made covers for public facilities via digital light processing, which is a popular 3D printing technique for satisfactory printing resolution. Potent efficacies of the 3D-printed plastics were achieved in standard antibacterial assessments against S. aureus, E. coli and K. pneumoniae. A total of 99.9% of Human coronavirus 229E was killed after being in contact with the 3D-printed samples (containing the promising PHMB formulation) for two hours. In an eight-week field test in Hong Kong Wetland Park, antibacterial performances of the specially designed 3D-printed covers analysed by environmental swabbing were also found to be satisfactory. With these remarkable outcomes, antimicrobial products prepared by digital light processing 3D printing can be regarded as a reliable solution to long-term infection prevention and control. [ABSTRACT FROM AUTHOR]