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The sol-gel method has been employed in the fabrication of mesoporous composite films consisting of a nonionic surfactant, Pluronic P123, as the organic component, and silica as the inorganic component. The hybrid nature of these films resulted in their having an internal structure consisting of nanometer size self-assembled organic mesostructures surrounded by a silica framework. These films served as the host matrix for the laser dye coumarin 481 (C481) and an energy transfer complex formed between C481 and J-aggregated meso-tetra(4-sulfonatophenyl)porphyrin (TSPP). Upon exposure to methanol vapor, a rapid and reversible decrease in fluorescence intensity occurs for films containing C481 alone as well as containing both C481 and TSPP. Steady-state and time-resolved spectroscopic studies suggest that the decrease in fluorescence intensity is primarily due to an excited state interaction between methanol and C481; while, additionally, morphological changes within the film appear to play a role for films containing both C481 and TSPP.

Multiwalled carbon nanotubes (MWCNTs) were dispersed in various alcohols such as methanol, ethanol and isopropanol using ultrasonication. In order to disperse the MWCNTs in the alcohols, they were treated using a mixture of H₂SO₄ and HNO₃ (3 : 1, vol/vol). The concentration of MWCNTs was approximately 0.03 wt.% and they formed a homogeneous dispersion in the alcohol solutions. The functional groups introduced on the surface of the MWCNTs during the acid treatment were characterized by Fourier transform-infrared spectroscopy and X-ray photoelectron spectroscopy. The dispersibility of the MWCNTs in the alcohols was characterized using atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The stability of the MWCNT dispersions was also measured using a recently developed optical analyzer (Turbiscan).

In this investigation, we have studied the kinetics and mechanism of photocatalytic conversion of methane into methanol reaction over the MoO₃(010) surface using a computer simulation method. Methane and oxygen as the reactants are used at room temperature and atmospheric pressure under UV photoirradiation of the catalyst. According to our data analysis, the order of methanol formation reaction with respect to CH₄ and O₂ was determined to be l=0.30 and m=-1.03, respectively. The highest methanol formation rate (TOF) value was obtained at about 0.05 molecule/s.site in a range of 25–35 W/cm² incident light intensity with energy hν≥E_g. The selectivity of CH₃OH was increased with increasing partial pressure of CH₄, while the selectivity of CHOH was decreased. The effect of light intensity on the CH₃OH selectivity was also studied under different P_CH4/P_O2 ratios, namely 0.9, 1.5 and 2.6. The highest CH₃OH selectivity was obtained at 1.5 ratio.

The adsorption of small organic molecules on silicon surfaces has been long a subject of investigations, as it provides the fundamental basis of silicon-based technologies in many fields. Several approaches were used, both theoretical and experimental, on many types of adsorbate-substrate systems aiming at determining preferential sites and geometries of adsorption, stable configurations, transition barriers, adsorption mechanisms, electronic structures among others. The research efforts, though, did not always bring to conclusive arguments and on some systems investigations are still going on following the evolution of the experimental techniques and computational methods. In this review, two case studies are reported: benzene and methanol on Si(100)2$\times$1, i.e. examples of a molecular and a dissociative adsorption. The adsorption of benzene on Si(100)2$\times$1 is still an open case, as it may adsorb in di-$\sigma$ or tetra-$\sigma$ bonded configurations, but contrasting evidences have been reported so far, on which of the two is the most stable one and the debate is still open. The adsorption of methanol is less controversial and it is widely accepted it is dissociative with breakage of the O–H at low coverages. But also in this case, investigations are going on to elucidate the adsorption mechanism.

The reaction mechanism of the decomposition of the methanol catalyzed by hydroxyl ZnO has been investigated by density function theory (DFT). The geometries of reactants, intermediates, transition states, and products on both doublet and quartet potential energy surfaces (PESs) have been fully optimized at the B3LYP/6-31G* level. The calculated results show that the reaction is slightly endothermic by 5.3 kJ/mol, which is in good accordance with the previous experiment. The energies and structures of the crossing points (CPs) between two PESs have been determined. The CP appears after the formation of transition states. The two theoretical models chosen to study the reaction mechanism were compared and discussed.

The reaction mechanism for methane hydroxylation catalyzed by mimic methane monooxygenase (MMO) with bis(μ-oxo)dimanganese core has been investigated on the septet and nonet potential energy surfaces by hybrid density functional method B3LYP. The key reactive compound Q of MMO was modeled by trans-(H₂CNH)(COOH) Mn(μ-O)₂(μ-HCOO)₂Mn(H₂CNH)(COOH). The ground state of Q is located on the septet state, which has a diamond-core structure with two Mn(IV) atoms. It is shown that the reaction proceeds via a radical-rebound mechanism, in which the step of C–H cleavage is the rate-determining step both in the gas phase and solution. Furthermore, the reaction may proceed more easily as the polarity of solution is larger. On the other hand, the kinetic isotope effects (KIEs) for H atom abstraction from methane are taken into account on the basis of transition state theory with Wigner tunneling corrections. The mimic MMO with bis(μ-oxo)dimanganese core might be an effective mimic catalyst for methane hydroxylation.

The possible paths of dimethyl ether (DME) synthesis from methanol over hydrated $\gamma$-Al₂O₃(110) in vacuum and liquid paraffin have been investigated by using density functional theory (DFT). Over hydrated $\gamma$-Al₂O₃(110), the three possible paths of methanol dehydration to DME have been investigated by the DFT method in vacuum and liquid paraffin. DME synthesis from methanol is carried out along the same pathway 2CH₃OH(g) $+$ 2* $\to$ 2CH₃OH* $\to$ 2CH₃O* $+$ 2H* $\to$ CH₃OCH₃* $+$ H₂O* in vacuum and liquid paraffin, and the step of highest energy barrier is the reaction of 2CH₃O* $\to$ CH₃OCH₃* $+$ O*. The energy barrier of the step in liquid paraffin is higher than that in vacuum by 0.33eV. The surface acid strength in liquid paraffin decreases over $\gamma$-Al₂O₃(110) surface comparing with vacuum, showing that stronger surface acid strength benefits to DME synthesis. Our result is in consistent with the experiment results.

Due to the importance of producing clean energy through systems such as alcoholic fuel cell, methanol, ethanol, 1-propanol, and 2-propanol, these alcohols were oxidized at the modified graphite electrode by NiTPPBr₆ / NiTPPBr₈ as a clean electrocatalyst in an alkaline media. This process investigated by various techniques such as cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS), in all cases showed Cottrell type behavior with the diffusion of coefficients of 2.04 × 10${}^{-6}$, 1.3 × 10${}^{-6}$ 8.3 × 10${}^{-6}$ cm${{}^2}^{}·$ s${}^{-1}$ for the corresponding alcohols respectively. Likewise, the catalytic rate constant for methanol oxidation was found to be 2.9 × 10⁸ cm³mol${{}^{-1}}^{}·$ s${}^{-1}$ through chronoamperometric measurements. Interestingly, the order in activity for oxidation of the alcohols introduced with the electrocatalyst was: 2-propanol $>$ 1-propanol $>$ ethanol $>$ methanol and was unlike previous studies in which the oxidation current was reduced by increasing the number of carbon atoms from methanol to propanol.

Ruthenium (II) polypyridyl complexes modified titanium dioxide materials with anatase phase, the length of 10–100nm, were synthesized by a hydrothermal method. Photocatalytic CO₂ reduction experiments were performed in sensitized TiO₂ aqueous suspensions under UV–Vis light in closed systems. And only methanol was detected in the liquid phase under the experiment condition. The effect of different photosensitizers content on the photoactivity of TiO₂ was also studied, showing that Ru(BiDiPy)₂(NCS)₂ sensitized TiO₂ was the optimal photocatalyst in transformation of CO₂ to methanol. A possible mechanism for the photocatalytic reduction was also proposed in this paper.

Conversion of methane into high value added chemicals and clean fuels such as methanol under mild conditions is of great importance to the chemical industry. However, traditional thermal catalytic of methane always suffer from harsh reaction conditions and poor product selectivity. Here, we reported photoelectrocatalytic oxidation of methane over BiVO₄/Au/FeCo–LDH under simulated sunlight illumination with ambient‘ conditions. The results demonstrate that BiVO₄/Au/FeCo–LDH exhibits excellent photoelectrochemical properties and catalytic activity. The double-layer capacitance ($C_{dl}$) value of BiVO₄/Au/FeCo–LDH is estimated to be 3.00mF$\cdot$cm${}^{-2}$, indicating its considerable electrochemical active areas. The photocurrent density of BiVO₄/Au/FeCo–LDH reaches up to 1.46mA$\cdot$cm${}^{-2}$ in methane atmosphere. The methanol yield for photoelectrocatalytic oxidation of methane is 8.46 times that of pure BiVO₄, and the corresponding Faraday efficiency is 56.09%. Finally, the reaction mechanism of photoelectrocatalytic conversion of methane to methanol based on hydroxyl radical and methyl radical as intermediate products is proposed. Our finding is expected to provide new insight for the design of active and selective catalysts toward photoelectrocatalytic conversion of methane.

Pt–Rh–Ru alloy catalysts for methanol electro-oxidation were prepared by electrochemical deposition under constant potential conditions. The Pt:Rh:Ru ratio was varied by changing electroplating solution composition. Obtained catalysts were examined electrochemically in acidic solutions containing methanol. Stripping voltammetry was applied to study adsorption of methanol on the electrodes surfaces while oxidation of methanol from solution was studied by means of chronoamperometry and cyclic voltammetry. The highest electrocatalytic activity was observed for an alloy with the highest obtained ruthenium concentration of 31%.

The aim of this paper is to develop a complete, precise and simple numerical model based on the thermophysical properties of an adsorptive cooling system (using activated carbon–methanol pair), analyze and discuss the heat and mass transfer processes and identify the parameters which influence the system performance. In the design of adsorption refrigeration system, the characteristics of both adsorbate–adsorbent pairs and system operating conditions are very important. So in this model, different thermophysical properties of working pair such as, specific heat, density, isosteric heat of adsorption and desorption, and different temperatures of the system are considered. A simulation code, written in FORTRAN, is carried out. The performance of the system is assessed in terms of refrigeration effect and coefficient of performance (COP).

All-atom molecular dynamics simulations have been performed on mixtures of tetrabutylammonium chloride-based deep eutectic solvent and two cosolvents — methanol and acetonitrile. Water, a highly polar protic solvent, strongly interacts with the DES components. Herein, we have chosen methanol, a protic solvent but less polar than water, and acetonitrile, an aprotic solvent, to investigate the structural modifications in DES and new interactions arising after the addition of cosolvent based on both polarity and the presence or absence of labile hydrogen. Of the two cosolvents, methanol is found to affect the interactions present in DES significantly. Strong hydrogen bond interaction occurs between the chloride anion and methanol, leading to changes in the behavior of the mixture at the microscopic level. The self-diffusivity of components of the DES increases with the addition of methanol and acetonitrile; however, the increase is relatively more significant in the latter due to fewer average numbers of H-bonds. The amplitudes of the peaks of the structure factor decrease with an increase in the cosolvent concentration, thereby confirming that cosolvent affects the long-range correlations.

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

The sol-gel method has been employed in the fabrication of mesoporous composite films consisting of a nonionic surfactant, Pluronic P123, as the organic component, and silica as the inorganic component. The hybrid nature of these films resulted in their having an internal structure consisting of nanometer size self-assembled organic mesostructures surrounded by a silica framework. These films served as the host matrix for the laser dye coumarin 481 (C481) and an energy transfer complex formed between C481 and J-aggregated meso-tetra(4-sulfonatophenyl)porphyrin (TSPP). Upon exposure to methanol vapor, a rapid and reversible decrease in fluorescence intensity occurs for films containing C481 alone as well as containing both C481 and TSPP. Steady-state and time-resolved spectroscopic studies suggest that the decrease in fluorescence intensity is primarily due to an excited state interaction between methanol and C481; while, additionally, morphological changes within the film appear to play a role for films containing both C481 and TSPP.

HZSM-5 catalysts synthesized by different templates, namely N-butyl amine (NBA), ethylenediamine (EDA), hexamethylene diamine (HDA) and directing agent (DA), were prepared using a simple hydrothermal synthesis method. The textural and acid properties of resultant catalysts were characterized using XRD, SEM, N₂ adsorption-desorption, NH₃-TPD, and Py-IR techniques. The methanol to aromatics (MTA) performance over the different catalysts was also investigated. The results showed that the type of templates significantly influenced the catalyst grain size, relative crystallinity, specific surface area and acid properties. The HZSM-5 catalyst synthesized by N-butyl amine has a smaller grain size, higher relative crystallinity and specific surface area, and proper acid properties. Furthermore, it exhibited the highest catalytic performance in methanol to aromatics (MTA) at 360°C.