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The number of newly synthesized and produced organic chemicals has increased extremely quickly. However, the measurements of their physical properties, including their vapor-liquid equilibrium (VLE) data, are time-consuming. It so happens that there is no physical property data about a brand-new chemical. Therefore, the importance of calculating their physicochemical properties has been playing a more and more important role. 4,6-Dichloropyrimidine (DCP) is also a relatively new molecule of high industrial importance with little existing data. Therefore, their measurements and the comparison with the calculated data are of paramount concern. DCP is a widespread heterocyclic moiety that is present in synthetic pharmacophores with biological activities as well as in numerous natural products. Isobaric VLE for the binary system of 4,6-dichloropyrimidine and its main solvent monochlorobenzene (MCB) was measured using a vapor condensate and liquid circulation VLE apparatus for the first time in the literature. Density functional-based VLE was calculated using the COSMO-SAC protocol to verify the laboratory results. The COSMO-SAC calculation was found to be capable of representing the VLE data with high accuracy. Adequate agreement between the experimental and calculated VLE data was acquired with a minimal deviation of 3.0 x 10-3, which allows for broader use of the results.

The exfoliation method was applied for the preparation of high-water selective mixed matrix membranes (MMMs), especially for the dehydration of C1–C3 alcohol–water solutions. Herein, a facile and easy method was employed to fabricate physically cross-linked Laponite nanosilicate clay–PVA MMMs without additional cross-linking by a one-step synthesis route for water dehydration from methanol, ethanol, and isopropanol aqueous solutions. The morphologies, chemical structures, thermal stabilities, and surface hydrophilicity of Laponite–PVA MMMs were investigated properly by different characterization techniques. The Laponite concentration has affected the fractional free volume of the membranes, as proven by positron annihilation lifetime spectroscopy analysis. The MMMs displayed both a significant improvement in the separation factor and remarkable enhancement in the permeation fluxes for the three alcohol systems. The influence of the operating temperature on the MMM performance was investigated for the methanol/water solution. The methanol permeability was 100-fold lower than that of the water, indicating that the membranes are more water selective. Particularly, the Laponite–PVA membrane with 5 mg/mL Laponite loading exhibits excellent separation efficiency for C1–C3 dehydration having water permeabilities higher than most other polymeric membranes from the other literature studies of 2.82, 2.08, and 1.56 mg m–1 h–1 kPa–1 for methanol, ethanol, and isopropanol/water systems, respectively. This membrane development allows a more efficient and sustainable separation of aqueous alcoholic mixtures.

Chemical industry has a high demand for ethylene quantity, especially with high quality. This paper discusses dynamic simulation models of an ethaneethylene high-pressure cryogenic rectification column with Unisim Design process simulator software. Distillation is one of the most essential technologies in chemical industry, it is important that the operation of the procedure can be modeled not only in steady-state mode but also in a dynamic way. The goal during this study is to make simulations with system-controlling and to investigate the effect the disturbance on the behavior of the columns.

Chemical laboratories badly need efficient support for human works when experiments are carried out. Process control and data acquisition at the laboratory scale are still practical challenges among others, due to equipment prices and the relative complexity of the different scientific disciplines. There is, however, a large demand recently for the so-called Internet of Things (IoT), intelligent/smart labeled solutions that also include laboratory equipment items. Such solutions have enormous potential in making research activity and routine laboratory work efficient and easy by implementing proper data acquisition and control for laboratory-scale equipment items. To solve these practical challenges, an efficient and simple solution was designed and completed for the control and data acquisition of a laboratory-scale rectification process by a well-known microcontroller connected to MATLAB/Simulink. The straightforward application of this solution is demonstrated in case study measurements. The data acquired were used also for process identification. The data were then further processed for various simple and more advanced tunings that were applied, evaluated, and compared. By implementing gain scheduling, significant improvements can be achieved compared to model-based PID tunings while the application of self-tuning by adaptive interaction demands too much consideration for better evaluation with low benefit. Furthermore, the developed device introduces the advantages of digitalization and the 4.0 industrial revolution in the laboratory as well as supports human laboratory work. It also narrows the gap between the laboratory and industrial environment items since the final design can provide a complete process control experience already at the laboratory scale.

There are different factors and indices to characterize the performance of a pervaporation membrane, but none of them gives information about their capabilities in the area of liquid separation compared to the most convenient alternative, which is distillation. Membrane flash index (MFLI) can be considered the first and only one that shows if the membrane is more efficient or not than distillation and quantifies this feature too. Therefore, the MFLI helps select the best separation alternative in the case of process design. In this study, the evaluation and capabilities of membrane flash index are comprehensively investigated in the cases of six aqueous mixtures: methyl alcohol–water, ethyl alcohol–water, isobutyl alcohol–water, tetrahydrofuran–water, N-butyl alcohol–water, and isopropanol–water. It must be concluded that the separation capacity of organophilic type membranes is remarkably lower than hydrophilic membranes in all cases of separation. The study of the MFLI is extended with the consideration of other binary interaction parameters like separation factor, permeation flux, selectivity, and pervaporation separation index (PSI) in order to find a descriptive relationship between them. For the same membrane material type, descriptive function can be determined between feed concentration and MFLI and PSI and separation factor, which can be used to calculate each other’s value. On the basis of the indices and especially the MFLI, a significant help can be given to the process design engineer to select the right liquid separation alternative and, in the case of pervaporation, find the most appropriate membrane.

In chemical recipes there can be found guidelines for efficient chemical production typically based on chemistry. However, such guidelines have never been checked with engineering methodologies for...

Thermal crosslinking sequential method applied for DN-PVAs generation efficiently. The swelling measurements investigated that the hydrophilicity of the membrane decreases because of the collaboration of the second thermal crosslinked PVA matrix. The dehydration performance of ethanol solution showed improved using the thermal crosslinked double network PVA membrane. The pervaporation dehydration of the water-ethanol mixture was investigated at different conditions. The separation selectivity showed a significant improvement, while the permeation flux declines due to the incorporation of the second PVA network under 95 % ethanol and at 40 °C. Increasing the feed temperature enhanced the permeability of the membrane, while decreasing the water content in the feed resulted in an increase in the selectivity. The overall results showed that, at high operating temperature and high ethanol concentration in the feed, the prepared membranes are highly selective towards the water with reasonable fluxes values. The influence of temperature permeation parameter and diffusion coefficient of the feed component is also discussed. The negative heat of sorption ( ∆Hs ) values calculated on the basis of the estimated Arrhenius activation energy values indicates that the sorption process is controlled by Langmuir's mode.

Laponite nanodiscs are low cost synthetic silicate clay with extreme hydrophilic behavior. Therefore, laponite can be used to enhance pervaporation membranes’ performance. Poly(vinyl alcohol), (PVA)/laponite pervaporation membranes were fabricated via simple exfoliation method of the nanoclay in the polymer solution followed by chemical crosslinking using glutaraldehyde (GA). The fabricated membranes were employed to study the pervaporation desalination performance when treating reverse osmosis (RO) concentrated brine solution. The effect of nanofiller concentration on membrane properties, as well as the water diffusion coefficient through the membrane, swelling measurements was investigated. The highest rejection of ∼99.98% was achieved using 7 wt% laponite nanocomposite membrane at 40 °C with a flux of 31.2 kg/m2 h. Increasing the feed concentration resulted in a decrease in water flux, whereas the salt rejection was negligibly changed. The influence of the operating temperature and feed salt concentration on the desalination performance 7 wt% laponite nanocomposite membrane (PVA7) were obtained at different temperatures in the range between 30 °C and 70 °C and feed concentration up to 100,000 ppm the temperature profile is expressed by Arrhenius relationship.

In the COVID-19 pandemic period, the role of face masks is critical as a protective physical barrier to prevent droplets and filtrate exhalations coming from infected subjects or against various environmental threats, including the SARS-Cov-2 virus. However, the plastic and microplastic waste from the used face masks pollute the environment, cause a negative impact on human health and the natural ecosystem, as well as increase landfill and medical waste. The presented paper focuses on providing an overview of the application of membrane technology in face mask products as well as the development of protection mechanisms in the future. The authors performed an environmental analysis of reusable (cloth) masks and disposable masks (surgical masks and filtering facepiece respirators) using the Life Cycle Assessment methodology to assess the impacts on the environment, human health, and ecosystem. IMPACT 2002+ V2.14, ReCiPe 2016 Endpoint (H) V1.02, IPCC 2013 GWP 100a V1.03 methods were applied using specialized software (SimaPro V9.1). The disposable masks consistently provide higher protection, though they also carry several multiple environmental burdens. Conversely, reusable masks improve environmental performance, reduce 85% of waste, have a 3.39 times lower impact on climate change, and are 3.7 times cheaper than disposable masks.

This study investigates the formic acid-mediated hydrothermal carbonisation (HTC) of microalgae biomass to enhance green hydrogen production. The effects of combined severity factor (CSF) and feedstock-to-suspension ratio (FSR) are examined on HTC gas formation, hydrochar yield and quality, and composition of the liquid phase. The hydrothermal conversion of Chlorella vulgaris was investigated in a CSF and FSR range of −2.529 and 2.943; and 5.0 wt.% – 25.0 wt.%. Artificial neural networks (ANNs) were developed based on experimental data to model and analyse the HTC process. The results show that green hydrogen formation can be increased up to 3.04 mol kg−1 by applying CSF 2.433 and 12.5 wt.% FSR reaction conditions. The developed ANN model (BR-2-11-9-11) describes the hydrothermal process with high testing and training performance (MSEz = 1.71E−06 & 1.40E−06) and accuracy (R2 = 0.9974 & R2 = 0.9781). The enhanced H2 yield indicates an effective alternative green hydrogen production scenario at low temperatures using high-moisture-containing biomass feedstocks.

The features of pervaporation are continuously improved with the production of more and more efficient membranes. In our present study, silver nanoparticles are in-situ generated in a poly (vinyl alcohol) using solution-casting in order to enhance its capability for pervaporation. The membrane is tested on the case study of ethanol dehydration by pervaporation. Effect of silver content on the pervaporation separation index and the enrichment factor of the membrane at 15 % mass water at 40 °C are reported. Pervaporation data for nanocomposite membranes show around 100 % increase in the water permeance values while the intrinsic selectivity decreases that is typical for pervaporation membranes. The water permeances of original crosslinked PVA membrane and the 2.5 % silver loaded PVA membrane are 26.65 and 70.45 (g/m2.kPa.h), respectively. The values of total flux are closely related to water flux, showing that membranes could be successfully assigned to separate water from ethanol even at the azeotropic point. The influence of temperature on the efficiency of the pervaporation process, permeation parameter and diffusion coefficient of the feed component is also discussed. The negative heat of sorption (∆Hs) values calculated on the basis of the estimated Arrhenius activation energy values indicates that the sorption process is controlled by Langmuir's mode. Our results show that the 0.5 mass% silver loaded poly (vinyl alcohol) membrane exhibits excellent PV performance.

Pervaporation (PV) has shown great promise in water desalination technology. In this work, Laponite XLG – Poly (vinyl alcohol) (PVA-Lap) mixed matrix membranes (MMMs) were fabricated to investigate the elaboration of desalination of high-salinity water by pervaporation. The influence of Laponite content on the morphology, chemical structure and hydrophilicity of the membranes was investigated. In addition, salt transport properties in the membranes were observed. Moreover, the effect of different Laponite content in the PVA matrix on the desalination performance was observed at temperatures from 40 °C to 70 °C and feed solutions with up to 10 wt% NaCl. The prepared MMMs showed higher hydrophilicity and roughness of the surface and higher mechanical stability. The higher water flux of 58.6 kg/m2 h with a salt rejection over 99.9% was achieved using 2 wt% Laponite XLG MMMs desalinating 3 wt% aqueous NaCl solution at 70 °C. The salt permeability in the membrane was lower by two orders of magnitude than that of water. The water/salt selectivity increased, while the water permeability decreased, with increasing of Laponite content in the membrane.

This study examines the light factorial optimization of Chlorella vulgaris microalgae cultivation under different wavelengths and light intensities. RGB light-emitting diodes were applied on microtiter plate and lab scale stirred tank photobioreactors. One-way ANOVA and response surface methodology were adopted to investigate the effects on biomass productivity. The highest biomass productivity is found at 243.5 and 96.8 μmol photon m−2 s−1 in case of red and blue color intensities, respectively. Scaled-up fermentation in stirred tank photobioreactors shows that changing light intensity and aeration settings result in differing biomass productivity and composition. The effects of targeted cultivation are investigated on hydrothermal gasification (HTG) which is carried out in tubular reactor system at 550 °C, 30.0 MPa and average 120 s residence time. It is found that the fermentation of microalgae under optimized light factor levels results in higher H2 yield compared to unoptimized light intensity levels. Throughout the HTG process high H2 yield is achieved (4.38–9.34 mol kg−1) without using any catalyst, which indicates that the efficiency of downstream processing can be increased already at the cultivation stage.

In the separation industry the extractive heterogeneous-azeotropic distillation (EHAD) is a new and powerful innovation, that is capable of making the separation of highly non-ideal mixtures feasible and economical. In the last years there has been much attention paid to the separation of the minimum boiling homogeneous azeotropes. Although maximum boiling azeotropes are fewer in numbers than the minimum boiling ones but their separation is more complicated but it could be solved with the EHAD, too. Since EHAD is not limited to the separation of minimum boiling azeotropes, the separation of the maximum boiling azeotropes is studied in this work. Our work is motivated by industrial problems because there are such maximum boiling azeotropes in the liquid wastes of the fine chemical industry. The separation of highly non-ideal Water–Acetone–Chloroform–Methanol and Water–Ethyl Acetate–Chloroform–Ethanol quaternary mixtures are investigated and optimized in professional flowsheet simulator environment. Total Annual Costs are also determined. The purity requirement is 99.5 m/m% for Chloroform and the bottom product should be as clear as possible in water so that less liquid organic waste has to be incinerated. It is also an important merit of the EHAD that the chemicals in the distillate can be usually reused supporting sustainability. Different solutions for the separations supplemented with heat integration are examined. On the basis of the computer simulations and the experimental verification it can be concluded, the first time on the literature, that the separation efficiency of EHAD is superior also for the separation of the maximum boiling azeotrope mixtures.

The problem of process wastewater arises not only in fine chemical industry, but also where water is used for washing. In these cases, surfactant material is given to the water, so its washing capability is enhanced. The used water contains surfactant material and dirt. It has high chemical oxygen demand (COD) resulting in serious environmental problems. Finding a solution is inevitable because of the high wastewater fine which has to be paid by the factories if wastewater is emitted without any treatment. A suitable method had to be found that follows the principles of circular economy, so the industrial cycles can be closed like in nature and the water can be reused. Our designed method focuses on different kinds of wastewater containing special surfactant materials, and it has chemical industry relations. The treatment should have reduced the high COD value below to 1000 mgO2/L, which is the discharge limit. It was also aimed that instead of discharging, the treated water could be recycled and reused. Our new physicochemical treatment process consists of a vacuum evaporation method that reduces COD from c.a. 8400 to 1100 mgO2/L. Both laboratory and pilot experiments were investigated. Since this COD value was not satisfactory, a subsequent reverse osmosis membrane operation was also applied. This two-step method, vacuum evaporator followed by reverse osmosis, was able to reduce the COD in wastewater containing surfactant/washing material below the discharge limit. 100 mgO2/L could be reached with using TriSep™ X201 membrane. Penalty calculation and cost estimation also demonstrate the efficiency of our novel method.

In the course of the present study, the pervaporative dehydration of two ternary mixtures: ethanol/n-butanol/water and ethanol/ethyl acetate/water were investigated through hydrophilic polymer composite PERVAP 1210 membrane. The effects of temperature and the concentrations of water and organic components on permeation were studied through pervaporation experiments. The influence of Hansen solubility parameters of the components and mixtures on their permeation was also examined. It has been found that changes of organic ratios in the feed solution affect organic permeation due to mutual interactions and flux coupling. This interaction was built in a suggested semi-empirical mass-transport model for ternary mixtures with optional simplifications. The modeled partial fluxes are in good accordance with the measured values.

The present work was performed because of the paramount importance of terephthalic acid (PTA) in the current chemical industry. It represents the missing element for the production of 100% bio-PET (polyethylene terephthalate) and has a market with continuous growth. The other monomer, monoethylene glycol (MEG), is already widely available from renewable sources. Considering the wide relevance, not only scientific but also social, covered by the possibility of producing one of the most frequently used polymers from renewable sources, this analysis is aimed at the environmental assessment of alternative routes for the production of PTA. In order to do this, the life cycle assessment (LCA) methodology was adopted as a scientific tool which is able to estimate the environmental performance of three pathways from different renewable sources, comparing the results with the traditional technology. An early stage approach was used by comparing different scenarios with two independent methods: CED (cumulative energy demand) and ReCiPe. The results prove that the bio-routes to PTA could be very competitive, in particular, if organic waste streams are converted into raw materials for the production of building blocks. On the other hand, the adoption of dedicated crops has some limitations and it seems not to be the right solution to mitigate climate change by reducing fossil sources.

Thermal crosslinked double-network poly (vinyl alcohol) (PVA) is prepared by applying the sequential method. The obtained membrane is characterized by thermogravimetric analysis (TGA), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy and contact angle analyses. It is concluded from FTIR analysis, contact angle measurements and measuring of swelling degree at different feed concentrations that the interpenetrating of the second network, that is the double network (DN), decreases the hydrophilicity of the membrane, while improving the thermal behavior and stability under high temperature. For the sake of the comparison of PVA and DN-PVAs selectivity, total permeation flux, individual fluxes and pervaporation separation index are evaluated for the dehydration of ethanol solution with a feed composition of 85/15 wt% ethanol/water solution at 40–60 °C. Furthermore, the effect of feed temperature on the permeation flux is expressed by the Arrhenius relationship. The performance of DN-PVAs membrane is appraised according to the change in feed concentration and operating temperature. The ethanol concentration in the feed is 75–95 wt% the DN-PVAs has flux values in the range of 41–414 g/m2 h and separation factor of 105–376 at the operating temperature 40–60 °C.

The fluctuating energy supply at different places of the Earth is a natural phenomenon since the most important energy source on planet Earth is the Sun, that is, solar energy. Humans have been the beneficiary of this natural phenomenon. Making a fire with wood uses stored solar energy. Utilization of biomass, however, is limited by the finite area of arable lands. The housing structures do that job and protect us against external hot or cold temperatures. In the industry, e.g., steel industry, so-called recuperators are applied. The latent heat method is more powerful than the use of sensible heat. Molten material can store heat more efficiently: A large amount of heat can be stored in a small volume. The hydrogen pressure also has an important effect on methane yield. Low pressure of hydrogen is preferred by oxidizing organisms, but high pressure of H2 is needed for methanogens.

This work aims to improve the synthesis of renewable hydrochar (HC) co-fired with coal to reduce grenhouse gas (GHG) emission. Acetic acid catalyzed hydrothermal carbonization (cHTC) of Chlorella vulgaris microalgae biomass was investigated based on a 3(3-1) fractional statistical design of the experiment to examine the effects of hydrothermal reaction temperature (T = 180-220 degrees C), biomass-to-suspension-(BSR = 5-25 wt.%), and catalyst-to-suspension (CSR = 0-10 wt.%) ratios on process performance indicators. Analysis of variance was used to assess the experimental data. The results show that the application of homogeneous catalyst improves the fuel ratio and energy recovery efficiency up to 0.38 and 36.3%. Ex-ante cradle-to-gate life cycle assessment was performed to evaluate the impacts of co-firing ratio (CFR) and hydrochar quality on multi-perspective mid-, and endpoint environmental indicators. The highest decarbonization potential (1.54 kg CO2,eq kWh(-1)) is achieved using catalytic hydrochar biofuel produced at 195 degrees C, 25 wt.% BSR, and 8 wt.% CSR levels. The application of catalytic and autocatalytic hydrochar blends improves the overall environmental impacts and greenhouse gas footprint of solid fuel firing facilitating the transition toward low-carbon emission power generation.

Global warming and climate change urge the deployment of close carbon-neutral technologies via the synthesis of low-carbon emission fuels and materials. An efficient intermediate product of such technologies is the biomethanol produced from biomass. Microalgae based technologies offer scalable solutions for the biofixation of CO2, where the produced biomass can be transformed into value-added fuel gas mixtures by applying thermochemical processes. In this study, the environmental and economic performances of biomethanol production are examined using artificial neural networks (ANNs) for the modelling of catalytic and noncatalytic hydrothermal gasification (HTG). Levenberg-Marquardt and Bayesian Regularisation algorithms are applied to describe the thermocatalytic transformation involving various types of feedstocks (biomass and wastes) in the training process. The relationship between the elemental composition of the feedstock, HTG reaction conditions (380 ?C & ndash;717 ?C, 22.5 MPa & ndash;34.4 MPa, 1 & ndash;30 wt% biomass-to-water ratio, 0.3 min & ndash;60.0 min residence time, up to 5.5 wt% NaOH catalyst load) and fuel gas yield & composition are determined for Chlorella vulgaris strain. The ideal ANN topology is characterised by high training performance (MSE = 5.680E-01) and accuracies (R-2 >= 0.965) using 2 hidden layers with 17-17 neurons. The process flowsheeting of biomass-to-methanol valorisation is performed using ASPEN Plus software involving the ANN-based HTG fuel gas profiles. Cradle-to-gate life cycle assessment (LCA) is carried out to evaluate the climate change potential of biomethanol production alternatives. It is obtained that high greenhouse gas (GHG) emission reduction (-725 kg CO2,eq (t CH3OH)-1) can be achieved by enriching the HTG syngas composition with H2 using variable renewable electricity sources. The utilisation of hydrothermal gasification for the synthesis of biomethanol is found to be a favourable process alternative due to the (i) variable synthesis gas composition, (ii) heat integration, and (iii) GHG emission mitigation possibilities.

Encouraged by the industrial problem of removing water from methanol solutions, a simple exfoliation method is applied to prepare polyvinyl alcohol (PVA)/laponite nanoclay mixed matrix membranes (MMMs). The membranes are used for the pervaporative dehydration of the methanol-water solution. The influence of the nanoclay content on the pervaporation performance is investigated. The results show that the PVA10 membrane containing 10 wt% Laponite loading exhibits excellent separation efficiency, therefore, all the experimental work is continued using the same membrane. Additionally, the effects of feed concentration and temperature on methanol dehydration performance are thoroughly investigated. The temperatures are ranging from 40&ndash, 70 &deg, C and the water feed concentrations from 1&ndash, 15 wt% water. A maximum separation factor of 1120 can be observed at 40 &deg, C and the feed water concentration of 1 wt%. Remarkably, two solution&ndash, diffusion models, the Rautenbach (Model I) and modified method by Valent&iacute, nyi et al. (Model II), are used and compared to evaluate and describe the pervaporation performance of the mixed matrix membrane. Model II proves to be more appropriate for the modeling of pervaporative dehydration of methanol than Model I. This work demonstrates that PVA/nanoclay mixed matrix membranes prepared can efficiently remove water from methanol aqueous solution with pervaporation and the whole process can be accurately modeled with Model II.

The low efficiency of renewable electricity storage has been considered as a bottleneck of the scalable and low-carbon Power-to-Gas energy transformation concept. This paper investigates the combination of CO 2 biofixation using Spirulina platensis microalgae and catalytic hydrothermal gasification of wet organic feedstock for the storage of fluctuating electricity and direct utilisation of waste CO 2 . The presented method enables wet microalgae biomass conversion into H 2 and C1-C2 rich fuel gas stream using hydrothermal conversion that is valorised further to methane. For bridging the gap between theoretical investigations and the application of this approach, experiments were carried out at elevated temperatures (632.9-717.0 °C) based on a central composite design of the experiment. Biogas upgrading was evaluated by ASPEN Plus flowsheeting software. The results show that the proposed storage cycle outperforms the state-of-the-art biological and chemical-based Sabatier methanations with an overall round-trip efficiency of 42.3%. The optimised thermo-chemical process enables to achieve simultaneously high H 2 (9.05 mol kg−1) and CH 4 (7.91 mol kg−1) yields with an enhanced 71.23% carbon conversion ratio. Moreover, the environmental and cost evaluations of the currently proposed bio-synthetic process indicate low associated CO 2 equivalent emission (99.4 ± 12.6 g CO 2 , e q kWh−1) with 144.9 €MWh-1 normalised total annual natural gas production cost. Ideally the proposed storage cycle requires less H 2 from external sources, effective CO 2 utilisation becomes available through the biofixation and hydrothermal conversion of the wet organic feedstock and closed carbon emission cycle can be accomplished.

Pervaporation is a separation method that is considered as green technology because of its low energy consumption. The mechanism of component separation in a liquid mixture by pervaporation is complex but it can be explained with the solution-diffusion mechanism. The work is motivated by an industrial separation problem, that is, ethyl acetate removal from aqueous mixture. To complete this goal hybrid organophilic/hydrophilic pervaporation of ethyl acetate/water mixture through commercially available Sulzer PERVAP™ 4060 and 1510 membranes are investigated to obtain information about the removal of ethyl acetate. Our experimental data are evaluated with the pervaporation model of our improvement (Valentinyi et al., 2013) and it is found that the model can be applied also for both cases. The hybrid separation process is rigorously modelled in professional flowsheet environment, and optimized with the dynamic programming optimization method. The objective function is product purity of 99.0, 99.5 m/m% in water and ethyl acetate content and the total annual cost is also determined. It can be determined, this hybrid separation should be become the alternative of distillation if the energy prices are too high.

Carbon dioxide can be converted into fine chemicals such as methanol and thus, the produced renewable energy can be stored in chemical bonds through reductions. To achieve this, a water enhanced mechanism of CO2 hydrogenation leading to methanol has been designed by applying 1:3 (CO2 + 3H2) extended with a water molecule and a hydronium. The thermodynamic properties of the intermediate species and transition states have been calculated by using the W1U composite method. The energy efficiency of the studied mechanism is 27.1%. By understanding the mechanism, special purpose catalysts can be designed to accelerate carbon dioxide conversion.

The work is motivated by an industrial problem, which is alcohol removal from pharmaceutical process wastewater. The aim of the study was to develop a complete hybrid operation is investigated. Ethanol dehydration, in combination with distillation and hydrophilic pervaporation, is used to investigate about the extent of separation of the ethanol-water mixture. The aim of this research is to rigorously model and optimize this hybrid operation in professional flowsheet simulator environment. The number of minimal theoretical plates of distillation column and minimal effective membrane transfer area are determined. Cost estimation is also examined according to Douglas methodology. Considering our results it can be concluded that, the distillation and hydrophilic pervaporation processes are suitable for separation ethanol and water in 99.5 weight percent purity

Chemical process design is a creative step of engineers that should be supported by different computer-aided design tools. Such tools should be simple and easy to use because process synthesis often means the investigation of a huge number of alternatives. During the design of the separation of liquid mixtures, among many others, distillation and pervaporation are usually simultaneously considered because pervaporation is frequently considered as an alternative to distillation. To easily compare the efficiencies of continuous pervaporation and flash distillation, we propose a new and simple method, the so-called membrane flash index (MFLI). The comparison is based upon vapor–liquid equilibrium data and the permeation data of a pervaporation membrane and therefore can be plotted on a common chart in the case of binary mixtures. The permeation values of organophilic and hydrophilic pervaporations can be calculated with the help of known separation factors and feed concentrations. The MFLI is dimensionless a...

Washing detergents in process wastewaters from fine chemical industry produce high Chemical Oxygen Demand (COD), which poses a serious environmental problem. Method has to be found, which follows the principles of circular economy so that the treated water can be recycled or reused. Heat pump vacuum evaporator is evaluated in order to reduce the Chemical Oxygen Demand of process wastewater with washing detergent content from initial 7500 mg O2/L to a lower value below the effluent limit , which is 1000 mg O2/L. Yield and COD rejection are determined for the evaluation of selected treatment. Experiments are investigated with LED Italia R150-v3 pilot apparatus. Different evaporation pressures were applied during measurements. It The highest removal or reduction of in the Chemical Oxygen Demand was reached certainly using the lowest possible pressure, which is 40 mbar.

Different research works demonstrate that the pervaporation can replace the distillation or deliver better solutions. It should be, however, accepted with criticism. In our case study, isobutanol-water separation is studied since it is increasingly important in the field of biofuels and process wastewater treatment. There are many options for the separation and they differ in their efficiency, economic features, robustness, development level and environmental impact. Five separation structures are investigated using distillation, both organophilic and hydrophilic pervaporations and hybrid separation units consisting of distillation and pervaporation including heat integrated solutions. The different alternatives are modelled in professional flowsheeting environment. Life cycle assessment, energy evaluation and Multi-Criteria Decision Analysis (MCDA) based on PEST (Political, Economic, Social, and Technological) analysis are completed to evaluate and compare the five alternatives. The feed stream to be separated has the composition of 7 wt% isobutanol 93 wt% water that corresponds to the mixture of the phase split due to the limited solubility. Two product purities are considered, 98.8 and 99.9 wt%. In case of distillation processes, heat integration is also considered, that is, the feed is preheated with its bottom flow. Heat integration significantly improves the efficiency of the distillation and makes it for practically a competitive alternative. The best efficiency can be obtained with heat integrated hybrid separation, that is, the combination of distillation and pervaporation. The pure pervaporation that is the combination of organophilic and hydrophilic pervaporation can be efficient only at sloppy product purities because of the modest separation factor of the organophilic pervaporation membranes. In case of sharp separations, the organophilic pervaporation can be an equally applicable solution as the azeotropic distillation for isobutanol-water separation.

The work is motivated by a separation problem, which is ethanol removal from aqueous mixtures with membranes. Ethanol can be considered as promising biomass based platform molecule. The platform molecule includes several building-block chemicals grouped together, resulting in a range of downstream chemical products. To solve the target, organophilic pervaporation system is investigated using benchmarked Sulzer PERVAP™ 4060 membranes. Separation factors, total permeation fluxes, permeances and selectivities are experimentally determined. The target of this work is to parameter estimation for semi-empirical pervaporation model. The measured data are evaluated with improved pervaporation model by Valentinyi et al. [1]. Three different polymeric flat sheet membranes are investigated, PERVAP™ 4060, PERVAP™ 1060 and CELFA-CMG-OG010. It is found that the model can be applied also for each organophilic separation case.

Biodiesel production showed an immense increase worldwide in the past decade. Since the comprehensive analyses of biodiesel production processes and their comparative evaluation are both rare and not informative enough, e.g., for scientists and decision makers, in this work different, favored biodiesel production alternatives (rapeseed, soybean and palm) are analyzed from multiple viewpoints and compared. A complex examination is carried out with Political, Economic, Social, Technological, Legal and Environmental (PESTLE) analysis, where cradle-to-grave life cycle analysis is incorporated and performed within PESTLE factors. Life cycle inventory is set up based on Ecoinvent 3.3 database, while life cycle impact assessments are achieved by IPCC 2013, IMPACT 2002+, EPS 2000 and 2015dx methods. Monte Carlo analysis is also carried out in order to make certain about the robustness of input data. The investigated factors are weighted and ranked with multi-criteria decision analysis, wherein Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) method is applied for the comparison of alternatives. Our work presents a clear methodology for the comprehensive evaluation of biodiesel production alternatives, but the guideline can be followed for the evaluation of other production alternatives. In spite that the life cycle analysis shows the palm oil as the best alternative, the results of our comprehensive analysis show that the highest overall TOPSIS score can be achieved with rapeseed-based biodiesel pathway, especially for the European region.

This study continues our research about dividing-wall distillation columns (DWCs) with upper and lower partitions (Ind. Eng. Chem. Res. 2016, 56, 952). Thermodynamic efficiencies and heat demands are investigated to offer a more complex point of view about distillation technologies. Rigorous simulations of nine distillation systems are completed, and the results are evaluated. Among the separation systems there are conventional direct and indirect distillation systems and energy-integrated ones, that is, DWCs with upper and lower partition, columns with side stripper or side rectifier, the fully thermally coupled distillation column, the sloppy system, and a direct sequence with backward heat integration are examined using three different alcohol mixtures. Results are obtained from rigorous simulations using exergy analysis. Thermodynamic efficiencies are in agreement with the expectations based on previous researches. On the basis of the thermodynamic efficiencies and heat demands the direct sequence wit...

Hybrid separation materials intended for the hydrophobic pervaporation process with a new type of fillers were generated. Membranes based on poly(ether block amide) (Peba 2533) containing two organic fillers: 4-(trifluoromethyl)-N-(pyridine-2-yl)benzamide (denoted as F1) and 4-(dimethylamino)-N-(pyridine-2-yl)benzamide (denoted as F2) were fabricated. Novel materials were systematically characterized from the material point of view and subsequently applied in the pervaporative separation of binary water-organic mixture. The correlation between the type (e.g. hydrophobicity) and amount of the filler on the membrane performance has been discussed. The pervaporation performance was assessed for ethanol/water mixture containing 5 wt% ethanol at temperatures ranging from 30 °C to 60 °C. The separation factor (β), thickness normalized total and partial permeate fluxes (Jt,N and Ji,N), and thickness normalized Pervaporation Separation Index (PSIN) were utilized for evaluation of the process. The best efficiency in recovery of ethanol from a mixture containing 5 wt% of ethanol was found for the membranes containing 2.5 wt% of F1 (membrane denoted as PF1-2.5) and 10 wt% of F2 (membrane denoted as PF2-10). The incorporation of the organic fillers improved the pervaporation performance of the PEBA membrane, regarding both permeate flux and separation factor. The highest normalized flux of 28.9 μm kg m-2h−1 and separation factor of 4.6 was achieved at 60 °C, using PF1-2.5 in contact with 5 wt% ethanol as feed.

Carbon dioxide emission, one of the core cause of global warming and other threats of nonreversible environmental effects, is in focus today. Among the several methods of CO2 emission mitigation, post-combustion carbon capture (PCC), based on absorberdesorber systems with amine absorbents, is one of the promising alternatives. The major anthropogenic CO2 point sources are power plants, natural gas extraction units, oil refineries, cement factories, biogas plants, etc. As these CO2 sources can be treated with a PCC absorber-desorber system, then these two units should cope with various conditions. To maintain a desired high removal efficiency, the capture unit must work in flexible conditions. The aim of this study is to evaluate the influence of the extent of the absorption of carbon dioxide on the overall performance of the acid gas removal process, considering that, generally, as the amount of removed CO2 increases, the separation becomes more challenging. In this work a verified computer based process model for the absorber-desorber system is used. Aspen Plus® professional flowsheet simulator is used for this purpose. Attention is paid on the proper operating parameters of a PCC absorber-desorber system for the case of increasing the CO2 capture efficiency up to 99%. As alternative solutions for these cases different scenarios are considered: • the increase of the capacity of a classic configuration of an absorber-desorber system; • the introduction of a second absorber column as extending the absorption column height; • the possible use of two absorbers and two desorbers working in series. This work deals with the detailed study on maximizing CO2 removal efficiency while maintaining the minimal energy consumption for the absorbent regeneration section.

CO2 is the primary greenhouse gas (GHG) due to its large quantity of anthropogenic emission. In this work the amine based carbon capture process and the CO2 storage, called Carbon Capture and Storage (CCS) is analysed from different viewpoints. PESTLE (Political, Economic, Social, Technological, Legal and Environmental) analysis of the CCS alternatives (Fossil based, Improved process, Renewable based) is investigated in detail and the alternatives are also compared with the uncontrolled CO2 release using Life Cycle Assessment (LCA) methods. Life cycle inventory data is set up and analysed with four life cycle impact assessment methods. In order to conclude the comparison of CCS and the uncontrolled release of CO2 a Multi-Criteria Decision Analysis (MCDA) is also applied with Multi Attribute Value Theory (MAVT) method. Our results show that applying process improvement and renewable energy sources (e.g., biogas) for absorbent regeneration result in a CCS technology of much smaller environmental and social impacts, and therefore the CCS technology becomes more favorable than the uncontrolled release.

The aim of this study is to compare the controllability properties of conventional distillation sequences and dividing-wall columns with upper and lower partitions (DWCs). The controllability analysis methodology uses the Control Design Interface (CDI) module of Aspen Dynamics to obtain the state space representation of the studied systems. The frequency dependent controllability indices are calculated by Matlab on the basis of the matrices of the transferred state space representation. The study includes the examination of the conventional direct and indirect sequences and two DWCs systematically generated from the corresponding conventional sequences. Case studies are completed using ternary alcohol mixtures with different eases of separation. Results show that conventional distillation sequences have more favorable controllability properties than those of the DWCs if direct separation and mixtures with symmetrical ease of separation are considered. In the cases of mixtures with nonsymmetrical ease of s...