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With the rapid growth in the number of passenger cars (PCs) in China over the past decades, more than ten million tons of used tires have already become solid wastes and subsequently caused serious environmental issues. Due to the presence of synthetic rubber in PC tires, waste PC tires cannot be disposed through rubber reclaiming technology. Thus, waste PC tires have become one of fastest growing solid wastes in China. First, the current disposal capacity of the pyrolysis method, regarded as a promising technology for the disposal of waste PC tires, is surveyed and compared with other disposal methods mentioned in previous papers. Second, this work establishes a model to predict the total number of waste PC tires in the next five years depending on the rate of PC growth and current waste tire disposal capacity. Moreover, pyrolysis is evaluated on 15 collected waste PC tires selected from the most representative tire brands in the Chinese market. The corresponding results imply that ∼68.5% of S was into oil and ∼44.3% N and large amount of heavy metals resided in solid carbon which severely limit further applications. Finally, a new pyrolysis technology is introduced that may represent a solution to the limits in the application of tire disposal methods and relief for the coming waste tire crisis.

N2O is a greenhouse gas and a candidate oxidant. Volatile organic pollutants (VOCs) have caused great harm to the atmospheric ecological environment. Developing the technique utilizing N2O as the oxidant to oxidize VOCs to realize the collaborative purification has significant importance and practical value for N2O emission control and VOC abatement. Therefore, the study of N2O catalytic oxidation of tert-butanol based on zeolite catalysts was carried out. A series of molecular sieves, including FER, MOR, ZSM-5, Y, and BEA, were selected as the catalyst objects, and the 1.5% wt Fe and Co were, respectively, loaded on the zeolite catalysts via the impregnation method. It was found that the catalytic performance of BEA was the best among the molecular sieves. Comparing the catalytic performance of Fe-BEA under different load gradients (0.25~2%), it was found that 1.5% Fe-BEA possessed the best catalytic activity. A series of characterization methods showed that Fe3+ content in 1.5% Fe-BEA was the highest, and more active sites formed to promote the catalytic reaction. The α-O in the reaction eventually oxidized tert-butanol to CO2 over the active site. The Co mainly existed in the form of Co2+ cations over Co-BEA samples; the 2% Co-BEA possessing higher amounts of Co2+ exhibited the highest activity among the prepared Co-BEA samples.

The chlorine (Cl2) drying technology using ionic liquids (ILs) as absorbents was proposed for the first time and systematically investigated from the molecular level scaled up to the industrial level. The hygroscopic IL [EMIM][CH3SO3] was screened as a suitable absorbent from 238 potential IL candidates consisting of 14 cations and 17 anions, by calculating the Cl2 and H2O solubility and separation selectivity of Cl2 to H2O in different ILs based on the COSMO-RS model. The microscopic atomic and molecular insights into the separation mechanisms were deeply revealed by using COSMO-RS model analyses (i.e., σ-profiles, σ-potentials, excess enthalpies, entropies, and Gibbs free energies) and quantum chemistry calculation (binding energies and weak interaction analyses). The Cl2 solubility in pure IL and H2O + IL systems were predicted by the COSMO-RS model, and the results agree with the microscopic mechanism identification. Moreover, the strict equilibrium stage model employed with the COSMO-RS model parameters was built to perform the process simulation, and continuous Cl2 drying with ILs was conceptually designed and optimized at industrial scale. It was confirmed that [EMIM][CH3SO3] is a very promising absorbent leading to a less IL amount, a much lower energy consumption than the other IL [EMIM][BF4], which has a very bright industrialization potential used for Cl2 drying technology.

Direct oxidation of methane to methanol (DMTM), constituting a major challenge for C1 chemistry, has aroused significant interest. The present work reports the synergistic effect of neighboring [Fe]--[Cu] cations, which can significantly boost the CH3OH productivity (100.9 and 41.9 → 259.1 μmol∙g−1cat∙h−1) and selectivity (0.28 and 17.6% → 71.7%) of the best performing Fe0.6%Cu0.68%-BEA (relative to monomeric Fe1.28%- and Cu1.28%-BEA) during the continuous H2O-mediated N2O DMTM. The combined experimental (in situ FTIR, D2O isotopic tracer technique) and theoretical (DFT, ab initio molecular dynamics (AIMD)) studies reveal deeper mechanistic insights that the synergistic effect of [Fe]--[Cu] can not only significantly favor active O production (ΔG = 0.18 eV), but also efficiently motivate the reaction following a H2O proton-transfer route (ΔG = 0.07 eV), eventually strikingly promoting CH3OH productivity/selectivity. Generally, the proposed strategy by employing the synergistic effect of bimetallic cations to modify DMTM activity would substantially favor other highly efficient catalyst designs.

This work proposed to use the ionic liquid [EMIM][BF4] as absorbent for the absorption of gaseous acetic acid. The feasibility of this technology was investigated from molecular level to industrial scale. The acetic acid absorption experiment was carried out using [EMIM][BF4], and the removal ratio of acetic acid in the gas product can achieve 88.6% at 20 °C under atmospheric pressure at the laboratory scale. Based on the experimental results, a reliable strict equilibrium phase model embedding the parameters of the UNIFAC model was established. On this basis, the conceptual process design and optimization of acetic acid removal by [EMIM][BF4] at an industrial scale was done, and the most suitable design and operation parameters were obtained. For a further step, the binding energy between [EMIM][BF4] and acetic acid was calculated to give some insights into the separation mechanism, and the results indicate that the interaction between acetic acid and IL is much stronger than that between nitrogen and IL. Moreover, hydrogen bond can be formed between the cation-acetic acid as well as the anion-acetic acid. Keywords: Ionic liquid (IL), Gaseous acetic acid, Absorption, Process simulation, Separation mechanism

A series of Pd-La/SiO2/cordierite (cordierite = COR) and Pd-Zn/SiO2/COR bimetallic monolithic catalysts were prepared, characterized, and tested for the hydrogenation of 2-ethylanthraquinone (eAQ) as the key step of anthraquinone method for production of H2O2. It was found that the metal particle size is remarkably dependent on the Pd/M (M = La, and Zn) mass ratio of bimetallic monolithic catalysts. By virtue of its small metal particle size and the strong interaction, the 0.8% Pd-0.4% La/SiO2/COR monolithic catalyst presents the highest H2O2 yield (7.7 g L−1) and selectivity toward active quinones (95%), which is attributed to the addition of La leading to the synergistic effect between Pd and La. Moreover, the density functional theory (DFT) calculations for the adsorption of eAQ over the surface of Pd-La/SiO2/COR and Pd-Zn/SiO2/COR bimetallic monolithic catalysts have been conducted to further understand the mechanism of molecule–surface interactions between eAQ and the PdM(1 1 1) or Pd(1 1 1) surfaces. Detailed studies showed that the high catalytic activity of Pd-La/SiO2/COR bimetallic monolithic catalyst is attributed to the stronger adsorption between Pd3La1 (1 1 1) and the carbonyl group of eAQ.

Surface segregation constitutes an efficient approach to enhance the alkaline hydrogen evolution reaction (HER) activity of the bimetallic PtxNiy nanoalloys. Herein, we propose a new strategy by utilizing the small gas molecule of H2 as the structure directing agent (SDA) to in-situ induce Pt surface segregations over a series of PtNi5-n samples with extremely low Pt dopings (Pt/Ni = 0.2). Impressively, the sample of PtNi5-0.3 synthesized under 0.3 MPa H2 delivers an unprecedentedly low overpotential of 12.8 mV (-10 mA cm-2) and Tafel slop of 14.1 mV dec-1, which is superior than most of previously reported PtxNiy electrocatalyst. This is closely related to the strong in-situ inducing effect of H2 (0.3 MPa) leading to an obvious Pt-rich@Ni-rich core-shell nanostructure which can efficiently reduce the reaction Gibbs free energies. Finally, the specific mechanistic effects of H2 during PtNi5-n synthesis process are well illustrated based on the combined experimental and theoretical studies.

The vapor pressures of the binary systems formic acid/acetic acid +1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) were measured using a modified equilibrium still at temperatures ranging from 323.15 to 358.15 K and IL contents ranging from 0.1 to 0.9 in mass fraction. The predictive thermodynamic models (i.e., UNIFAC-Lei and COSMO-RS models) were used to predict the vapor pressures with the ARDs of 4.54% and 22.24% for formic acid, respectively, and 6.38% and 16.43% for acetic acid, respectively. This indicates that the UNIFAC-Lei model can give a quantitative description with high accuracy, while the COSMO-RS model can only be used as a prior model to give a qualitative prediction. Moreover, the excess enthalpies and σ-profiles were calculated by the COSMO-RS model to achieve further understanding on the thermodynamic behavior at molecular scale. It was found that the hydrogen bonding interaction (HHB) plays a dominant role to the total excess enthalpy, and the HHB is mainly dependent on acid components. For IL, the contribution of anion is larger than that of cation as confirmed by the σ-profiles.

Ethylene glycol (EG) is proposed as an entrainer for the separation of methylal and methanol by extractive distillation. The COSMO-RS model was used to screen the suitable entrainer in terms of selectivity and solvent capacity. EG is a suitable entrainer with a low environmental impact. Vapor–liquid equilibrium (VLE) experiments demonstrated that the relative volatility of methylal to methanol is significantly improved using EG as an entrainer. The new corresponding interaction parameters were obtained by correlating the VLE data using the UNIFAC model, and then they were introduced into the process simulation software. The extractive distillation process was simulated using the rigorous equilibrium stage model. The optimal operating conditions were obtained by sensitivity analysis. The simulation results showed that EG is effective and efficient for the separation of methylal and methanol. In addition, the COSMO-RS model provides some theoretical insights into the separation mechanism.

The separation of benzene and cyclohexane by extractive distillation was intensified with the addition of ionic liquid (IL) as entrainer. The IL [EMIM][BF4] was chosen in terms of selectivity and solvent capacity. Vapor-liquid equilibrium (VLE) experiments using pure N-methyl-2-pyrrolidinone (NMP), the NMP and IL mixture, pure sulfolane, and the sulfolane and IL mixture, were conducted. The VLE results indicated that NMP is more suitable than sulfolane, due to the poor miscibility of sulfolane and key components in a whole concentration range. Moreover, the addition of IL into NMP can slightly improve the relative volatility of cyclohexane to benzene with the NMP and IL mixed entrainers, but the concentration of volatile NMP in vapor phase decreases obviously with the addition of IL. Based on the experimental VLE data, the UNIFAC-Lei model was applied, and the corresponding interaction parameters were obtained. The extractive distillation process was designed and optimized with the equilibrium stage model, in which the UNIFAC-Lei model parameters were implemented. The simulated results indicated that the extractive distillation process was intensified by the addition of IL in saving energy and entrainer usage. Moreover, no extra equipment expense is needed compared with benchmark solvent.

This work focuses on the hydrodynamic and mass transfer performances in multiphase monolithic reactor with different distributors by the combination of experiments and CFD simulation. The experimental results showed that the pressure drop in the monolithic bed with packed bed distributor is lower than that with other distributors, and that the liquid holdup follows the trend of packed bed distributor > foam distributor > porcelain ring distributor. Moreover, the gas-liquid mass transfer coefficients increase with the increase of superficial velocities of both gas and liquid phases, and mainly depend on the superficial liquid velocity. The CFD simulation showed that the gas-liquid phase distribution is mainly dependent on the superficial velocity of liquid phase, and the changes of superficial gas velocity don’t have an obvious effect on the gas-liquid phase distribution. Furthermore, the experimental and simulated results showed that the mass transfer coefficients in the monolithic bed with packed bed distributor is much higher than those with foam distributor and porcelain ring distributor.

Structural effects on various imidazolium–based ionic liquids (ILs) (i.e., [C][A], [C] = [EMIM]+, [BMIM]+, and [OMIM]+; [A] = [BF4]–, [PF6]–, and [Tf2N]–) suitability as drying agents for gas dehydration processes are explored from thermodynamic and dynamic insights by quantum chemistry (QC) calculations and molecular dynamics (MD) simulations. It is found that [EMIM][BF4] is regarded as the most promising drying agent because it exhibits the lowest Henry’s law constant and highest diffusion coefficient of H2O among all ILs. The microscopic mechanism at molecular level is revealed based on QC calculations and MD simulations, and the results demonstrate that the IL (i.e., [EMIM][BF4]) simultaneously with the smallest cation and anion size corresponds to both the strongest hydrogen bond (HB) interaction of H2O–anion and the strongest HB together with van der Waals interactions of H2O–cation. This work provides a valuable guidance from viewpoint of thermodynamics and dynamics for developing and screening novel ILs for gas dehydration.

A series of Pd/zeolite/cordierite (zeolite = MCM-41, SBA-15, Beta, or MCM-22; cordierite = COR) monolithic catalysts, as well as Pd/ZIF-8/COR, Pd/Al2O3/COR, and Pd/SiO2/COR, were prepared, characterized, and evaluated for the hydrogenation of 2-ethylanthraquinone (eAQ) to 2-ethyl-9,10-anthrahydroquinone (eAQH2). We found that a 0.8% Pd/MCM-41/COR catalyst exhibited the highest H2O2 yield (7.54 g L−1) and selectivity (85.3%) toward active quinones for hydrogen peroxide (H2O2) production using the anthraquinone method. Notably, the Pd efficiency (1573 gH2O2 g−1Pd h−1) for the 0.8% Pd/MCM-41/COR monolithic catalyst was much higher than that of a commercial pellet catalyst (500 gH2O2 g−1 Pd h−1). The intrinsic kinetics of hydrogenation of eAQ over 0.8% Pd/MCM-41/COR was measured, and the kinetic equation parameters were incorporated into a computational fluid dynamics (CFD) model. The mass transfer coefficients for the monolithic catalysts are 5–20 times higher than the pelleted catalyst. In addition, we found that the gas-liquid mass transfer is the controlling step, showing the unique advantages of monolithic catalysts for process intensification.

The vapor pressures of water + 1-ethyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)-amide ([EMIM][Tf 2 N]) binary system at temperatures ranging from 323.2 to 358.2 K and mole fraction of ionic liquid (IL) ranging from 0.05 to 0.90 were measured using a modified equilibrium still. The results showed that with the addition of IL, the vapor pressure of binary system is lower. The predictive thermodynamic models, i.e., UNIFAC-Lei and COSMO-RS models were used to predict the vapor pressure with the ARDs of 3.55% and 7.69%, respectively. Then, the adsorption amount of H 2 O in [EMIM][Tf 2 N] and ZIF-7/ZIF-8 mixture were predicted by the lever rule combining the UNIFAC-Lei model with GCMC simulation. The predicted results show a satisfactory agreement with the experimental data. Moreover, the vapor pressures of water + [EMIM][Tf 2 N] + ZIF-7/ZIF-8 ternary systems were measured with the mass fractions of ZIF-7/ZIF-8 from 0.005 to 0.05. However, it was found that the addition of ZIFs into water and IL mixture has little effect on the vapor pressure in the concentration range investigated.

In this research, a hybrid Geographic Information System (GIS)-based watershed-scale inexact optimization approach was developed to identify the optimal spatially distributed network of constructed wetlands for NPS pollution control. Such an approach combined the GIS technology and fuzzy-stochastic two-stage programming (FSTP) into a general optimization framework. A GIS-based compound topographic index (CTI) was used to identify potential wetland sites at the watershed-scale, a GIS-based export coefficient model (ECM) was employed to estimate the nutrient load from NPS pollution, and the FSTP was used to map the optimal spatially distributed network of constructed wetlands for reducing the NPS pollution with the minimization of system costs under uncertainty. As an integration of two-stage stochastic programming (TSP) and fuzzy credibility chance-constrained programming (FCCP), FSTP can not only address dual uncertainties expressed as probability density functions and fuzzy membership functions but also provide an effective linkage between the pre-regulated management policies and the associated economic implications. The developed modeling system was applied to the planning of wetland network installation in the Songhuaba watershed, China. The optimization results can help watershed managers to obtain desired plans of wetland siting, and nutrient permit allocation for sub-basins under different confidence levels.

In this work, the gas-liquid two-phase flow patterns and characteristics in Taylor flow regime in monolith channel were simulated by means of volume of fluid (VOF) method taking benzene and propylene as model system. Four types of flow patterns (i.e., bubbly flow, Taylor flow, Taylor-annular flow, and annular flow) were first identified in the range of gas velocity from 0.01 to 3.0 m s −1 and liquid velocity from 0.01 to 0.05 m s −1 . Then, the effect of contact angle and superficial velocity on hydrodynamic performance was investigated, confirming that the angle 0° is more appropriate. The hydrodynamic performance was intensified in the region of thin liquid film between gas bubble and the wall as well as the interface between gas bubble caps and liquid slug. Finally, the mass transfer performance of two-phase flow in monolith channel was investigated using one Taylor unit cell model. It was found that the mass transfer coefficients for monolith catalyst in Taylor flow regime is at least one order of magnitude higher than those for both structured catalytic packings and traditional pellet catalyst, exhibiting the advantage of monolith catalyst for process intensification.

In this work, a series of Pd/SiO 2 /COR (cordierite) catalysts with different Pd contents were successfully prepared by impregnation method. The obtained Pd/SiO 2 /COR catalyst samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), BET, hydrogen temperature programmed reduction (H 2 -TPR), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and X-ray photoelectron spectroscopy (XPS). X-ray photoelectron spectroscopy (XPS) show that Pd element is mainly in the state of PdO, and 1.5% Pd/SiO 2 /COR catalyst with the theoretical Pd content of 1.5% has the most PdO content on the monolith channel surface when compared to other Pd content monolith catalysts in this paper. Then in the experiment it was found the optimum catalyst is 1.5% Pd/SiO 2 /COR, which is consistent with XPS results. The STY can achieve 793.2 g H 2 O 2 g −1 Pd h −1 over 1.5% Pd/SiO 2 /COR catalyst.

Three types of structured packings with wave-like corrugated sheets were investigated, aiming to improve the hydrodynamics of structured packings. The experimental results showed that the new proposed structured packings have a significant advantage in pressure drop and capacity over traditional Mellapak 125X. A modified multi-scale CFD (computational fluid dynamic) model was applied to characterize the hydrodynamic performance of the novel packings. At the micro-scale (corrugation scale), a 2D VOF (volume of fluid) model was used to trace the gas–liquid interface and to calculate the liquid film thickness for two-phase flow; then, a 3D VOF model was used to calculate the effective wetting area at the meso-scale (packing element scale). Finally, a 3D porous media model was proposed to calculate the dry and wet pressure drops at the macro-scale (column scale). The average relative deviations between the experimental data and the calculated results for dry and wet pressure drops were 7.26% and 8.24%, respectively, confirming validity of the CFD simulations. The proposed modified multi-scale CFD model can be used effectively to design and optimize complex structured packings.

Three commonly used distributors (i.e., nozzle, packed bed, and foam) were introduced into a multiphase monolith reactor in this work to investigate the pressure drop, liquid holdup and gas–liquid distribution performance by combining experimentation and CFD simulation. The experimental results showed that the nozzle distributor exhibited the better gas-liquid phase distribution and the lowest pressure drop. However, so far, the gas and liquid velocities at the top of the monolith bed, which are crucial for the transition from a single channel to bed scale, have not been studied. Thus, a discrete phase and continuous phase coupling 3D model using CFD simulation was established for the nozzle distributor, and the magnitude and distribution of the gas and liquid velocities at the entrance of the monolith module were investigated. The simulation results showed that the droplets’ velocity reaching the monolith module was very high and had a strong influence on the gas velocity distribution. The increase in superficial gas velocity could enhance the gas distribution to some extent.

The vapor pressures of the binary systems (water + [OMIM][BF4], water + [OMIM][Tf2N], and water + [OMIM][PF6]) were measured by a modified equilibrium still at temperatures ranging from 323.15 to 358.15 K and water mole fraction ranging from 0.1 to 0.9 for water + [OMIM][BF4], from 0.1 to 0.4 for water and [OMIM][Tf2N] and from 0.05 to 0.45 for water + [OMIM][PF6] binary systems, respectively. The experimental results indicate that with the addition of ionic liquids (ILs) the vapor pressure of binary systems decreases. In addition, the popular and widely used UNIFAC-Lei model was extended to the corresponding systems to predict the vapor pressures with the average relative deviations (ARDs) of 4.99%, 4.71% and 5.15% for water + [OMIM][BF4]/[OMIM][Tf2N]/[OMIM][PF6] systems, respectively. Moreover, the binding energy, excess enthalpies and σ-profiles were investigated to analyze the thermodynamic behavior at the molecular level. It was found that the interaction between [OMIM][BF4] and water is significantly higher than those between [OMIM][Tf2N]/[OMIM][PF6] and water as shown by the σ-profiles and the binding energy, and the hydrogen bonding interaction is the dominant driving force contributing to the overall excess enthalpy.

In this study, a mixture of N-methyl-2-pyrrolidinone (NMP) and ionic liquid (IL) was proposed as the entrainer for the separation of benzene and thiophene by extractive distillation. [EMIM]+[BF4]− might be a suitable IL for investigating the selectivity and capacity together using the COSMO-RS model. The experimental vapor–liquid equilibrium (VLE) results indicated that the addition of IL did not obviously improve the relative volatility of benzene to thiophene; however, the content of NMP in the vapor phase could be significantly reduced using the combination of NMP and [EMIM]+[BF4]− in comparison to the benchmark solvent NMP. Moreover, the UNIFAC model was extended and the corresponding interaction parameters were obtained by correlating the ternary (benzene + thiophene + NMP) and quaternary (benzene + thiophene + NMP + [EMIM]+[BF4]−) VLE equilibrium data obtained in this work at ambient pressure.

In this research, a simulation-based fuzzy possibilistic programming (SFPP) model was advanced through integrating California puff (CALPUFF), fuzzy sets theory and inexact optimization within a general framework. It has advantages in uncertainty reflection, pollutant dispersion modeling, and the management of coal blending and the related human health risks. The developed SFPP model was solved through a direct search approach which coupled fuzzy simulation and Genetic Algorithm (GA). This approach can not only handle a coupled simulation–optimization problem considering uncertainties that can be expressed as fuzzy sets, but also provided the additional information (i.e. possibility of constraint satisfaction) indicating that how likely a decision maker can believe the decision results. It also can reduce the chances of being trapped in local optima as GA converges to global optima. Moreover, the employed direct search method can avoid the approximation error originating from surrogate simulators and enhance the confidence level of the generated optimal solutions. The developed model was applied to the planning of coal blending in Gaojing and Shijingshan power plants in the west of Beijing. The results indicated that the developed SFPP model was useful for generating a series of coal blending schemes under different acceptable possibility levels, ensuring that the risk to human health reduce to an acceptable level, identifying desired coal blending strategies for decision makers, and considering a proper balance between system costs and acceptable possibility levels.

This work investigates structured catalytic packings in a bubble-point reactor in which the reaction and flash occur simultaneously. A three-dimensional (3D) computational fluid dynamics (CFD) model was used to determine the optimum operating conditions and to examine the reactor performance when traditional catalyst pellets were replaced with BeiHua (BH) structured catalytic packings for benzene alkylation with propylene. It was found that the optimum operating conditions were a reaction temperature of 160 °C and a molar ratio of benzene to propylene in the feed of 4.0. In this work, we also explored the relationship between the geometric configuration and the reactor performance. The momentum transfer (pressure drop), heat transfer (Nu number), mass transfer (Sh number), propylene conversion, cumene selectivity, and effectiveness factor were determined for different geometric configurations, which included changes in the corrugation angle, ratio of the packing height to the diameter, and ratio of the areas of the reaction to open-channel regions. Two new types of transition or wave-like structures (30–45–30° and 45–30–45°), which resulted in a higher propylene conversion, cumene selectivity, and effectiveness factor, were adopted. Furthermore, the applicability of this new technology for benzene alkylation with propylene was verified in a pilot plant.

This work deals with the transfer and reaction performances for the alkylation of benzene with propylene to produce cumene over monolith catalysts by means of the combination of experiments and computational fluid dynamics (CFDs). A three-dimensional (3D) mathematical model was established to identify the geometric configuration–performance relation so as to provide a comprehensive comparison of momentum transfer (pressure drop), heat transfer ( Nu number), mass transfer ( Sh number), and reaction performances (i.e. propylene conversion, cumene selectivity, and effectiveness factor) among monolith catalysts with five kinds of channel shapes (i.e. circle, hexagon, square, rectangle, and regular triangle). The objective of this work is to address the cogently interesting issues as to (i) whether or not monolith catalysts can improve the transfer and reaction performances for the alkylation of benzene with propylene in comparison with the traditional pellet catalyst or even structured catalytic packing; (ii) which kind of channel shape is optimum from the viewpoint of chemical reaction engineering; and (iii) how much energy can be reduced in the actual process consisting of a gas–liquid–solid bubble-point reactor and two distillation columns. It was found that monolith catalyst exhibits the lower pressure drop, higher cumene selectivity and higher effectiveness factor; and regular triangle or rectangle channel is optimum when considering pressure drop and cumene selectivity together. Furthermore, the advantages of monolith catalyst can lead to the lowest energy consumption for the whole process.

This work focuses on the extension of group parameters and application of the group-contribution lattice-fluid equation of state (GCLF EOS) for the systems with ionic liquids (ILs). The new group parameters e kk and R kk for ILs in GCLF EOS were obtained by means of correlating the liquid density of pure ILs at different temperatures, while the group binary interaction parameters α mn were obtained by means of correlating the activity coefficients of solutes at infinite dilution in ILs at different temperatures, which were exhaustively collected from references. New IL groups were added into the current parameter matrix. It was verified that GCLF EOS for ILs can be used for predicting liquid densities of pure ILs or the mixture of IL and solute, vapor–liquid equilibria (VLE) and liquid–liquid equilibria (LLE) at finite concentration, as well as identifying the structure–property relation in separation science. This is the first work for us to extend the predictive GCLF EOS to the systems with ILs.

The intrinsic kinetics of liquid phase catalytic dehydration of methanol to dimethyl ether over a macroporous sulphonic acid ion exchange resin was determined in a fixed-bed micro-reactor in the temperature range of 391–423 K and pressures up to 2.0 MPa. The kinetic model based on Eley–Rideal mechanism, as well as the power-rate law model, was adopted for fitting the experimental data. However, the Langmuir–Hinshelwood mechanism is not feasible for describing the dehydration reaction of methanol, as deduced from the macroscopic kinetic data and/or no dependence of methanol conversion on initial methanol concentration in the absence of water at the inlet using acetone as inert solvent. Moreover, an improved process consisting of the combination of a fixed-bed reactor and a catalytic distillation column for the synthesis of DME (Process A) was proposed, and a mathematical model was established, into which the intrinsic kinetics obtained in this work was incorporated. The comparison of operating performance among the improved process, Process B consisting of a fixed-bed reactor and two ordinary distillation columns, and Process C consisting of a catalytic distillation column and an ordinary distillation column was also made. It was found that the improved process is more promising than others in energy consumption, production capacity and column number under the same product purity, and is easy to be implemented based on Process B that is currently used in the actual industrial plants with a long catalyst lifetime.