Milica Preradovic, Saša Papuga, Aleksandra Kolundžija
There is an urgent need for replacement of fossil fuels worldwide. Raw biomass has a low energy density, contains too much moisture, can rot, and it is hygroscopic. This paper presents a very prominent thermal technology that could overcome mentioned deficiencies of raw biomass. This technology is known as torrefaction. Torrefaction is mainly used to convert lignocellulosic materials into 'fuels' that can be used in power plants, combustion units, or gasifiers.
{"title":"Torrefaction: Process Review","authors":"Milica Preradovic, Saša Papuga, Aleksandra Kolundžija","doi":"10.3311/ppch.20636","DOIUrl":"https://doi.org/10.3311/ppch.20636","url":null,"abstract":"There is an urgent need for replacement of fossil fuels worldwide. Raw biomass has a low energy density, contains too much moisture, can rot, and it is hygroscopic. This paper presents a very prominent thermal technology that could overcome mentioned deficiencies of raw biomass. This technology is known as torrefaction. Torrefaction is mainly used to convert lignocellulosic materials into 'fuels' that can be used in power plants, combustion units, or gasifiers.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"2015 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73554390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biosurfactants are emerging molecules in the 21st century. However, their production intensification is still required for the development of feasible bioprocesses. Therefore, this paper studies a new biosurfactant-producer, namely Geobacillus stearothermophilus DSM2313 during statistical optimization via response surface methodology. After the statistical analysis the optimal pH = 7, glucose = 50 g/L and NH4NO3 = 2 g/L concentrations were determined. The biosurfactant production of the bacteria was predicted by our developed artificial neural network. The optimal harvesting time of the broth and the emulsification index values can be predicted simultaneously with the constructed artificial neural network. The best experiment was also kinetically described, and kinetic constants observed. Surface tension and emulsification activity were measured to characterize the formed products' efficiency. Based on these results, biosurfactants from Geobacillus stearothermophilus DSM2313 can act as bioemulsifier and can be applied for example in microbial enhanced oil recovery.
{"title":"Modeling the Biosurfactant Fermentation by Geobacillus stearothermophilus DSM2313","authors":"Réka Czinkóczky, Á. Németh","doi":"10.3311/ppch.20797","DOIUrl":"https://doi.org/10.3311/ppch.20797","url":null,"abstract":"Biosurfactants are emerging molecules in the 21st century. However, their production intensification is still required for the development of feasible bioprocesses. Therefore, this paper studies a new biosurfactant-producer, namely Geobacillus stearothermophilus DSM2313 during statistical optimization via response surface methodology. After the statistical analysis the optimal pH = 7, glucose = 50 g/L and NH4NO3 = 2 g/L concentrations were determined. The biosurfactant production of the bacteria was predicted by our developed artificial neural network. The optimal harvesting time of the broth and the emulsification index values can be predicted simultaneously with the constructed artificial neural network. The best experiment was also kinetically described, and kinetic constants observed. Surface tension and emulsification activity were measured to characterize the formed products' efficiency. Based on these results, biosurfactants from Geobacillus stearothermophilus DSM2313 can act as bioemulsifier and can be applied for example in microbial enhanced oil recovery.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"42 8 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88170318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nowadays, the drinking water shortage is increasing, mainly due to rapid population growth, climate change, wasteful overuse of water, and pollution. Under the current circumstances, a quarter of the world's population will not have access to good quality drinking water. Thus, another solution must be adopted in areas with insufficient freshwater. One possible line is the desalination of seawater, one of the most practical solutions to solve the problem of drinking water shortage along the oil availability shore and continues to expand globally. Water produced may also be utilized for irrigation, reducing a region's reliance on imports, contributing to the local economy, and improving food supplies. However, this process is not a consequences-free procedure; it may cause several environmental and human health problems.The three most applied desalination technologies are reverse osmosis (RO), multi-stage flash distillation (MSF), and multi-effect distillation (MED). In this study, the emissions of greenhouse gases (GHGs) of drinking water produced from seawater using these three technologies with fossil and renewable energy sources were investigated based on two methods: life cycle assessment (LCA) using SimaPro life cycle analysis software and carbon footprints. As a result, RO technology has significantly lower CO2 emissions than thermal technologies. The RO combined renewable energy is the most environmentally friendly; provides outstanding benefits in terms of human health and ecosystem quality. This technology may still evolve in the future to produce longer-lasting, cheaper membranes, and the energy requirements of this process are lower with applying modern energy recovery systems.
{"title":"Investigation of Carbon Footprints of Three Desalination Technologies: Reverse Osmosis (RO), Multi-Stage Flash Distillation (MSF) and Multi-Effect Distillation (MED)","authors":"Huyen Trang Do Thi, A. Tóth","doi":"10.3311/ppch.20901","DOIUrl":"https://doi.org/10.3311/ppch.20901","url":null,"abstract":"Nowadays, the drinking water shortage is increasing, mainly due to rapid population growth, climate change, wasteful overuse of water, and pollution. Under the current circumstances, a quarter of the world's population will not have access to good quality drinking water. Thus, another solution must be adopted in areas with insufficient freshwater. One possible line is the desalination of seawater, one of the most practical solutions to solve the problem of drinking water shortage along the oil availability shore and continues to expand globally. Water produced may also be utilized for irrigation, reducing a region's reliance on imports, contributing to the local economy, and improving food supplies. However, this process is not a consequences-free procedure; it may cause several environmental and human health problems.The three most applied desalination technologies are reverse osmosis (RO), multi-stage flash distillation (MSF), and multi-effect distillation (MED). In this study, the emissions of greenhouse gases (GHGs) of drinking water produced from seawater using these three technologies with fossil and renewable energy sources were investigated based on two methods: life cycle assessment (LCA) using SimaPro life cycle analysis software and carbon footprints. As a result, RO technology has significantly lower CO2 emissions than thermal technologies. The RO combined renewable energy is the most environmentally friendly; provides outstanding benefits in terms of human health and ecosystem quality. This technology may still evolve in the future to produce longer-lasting, cheaper membranes, and the energy requirements of this process are lower with applying modern energy recovery systems.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"31 4 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77451087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Csizmadia, Gergely Dombóvári, S. Till, Martin Minkó
The appropriate estimation of frictional losses in a pipeline system is essential. So far, little attention has been paid to determining the friction factors with non-Newtonian fluids, especially in rough pipes. This study aims at calculating the friction factor using validated three-dimensional Computational Fluid Dynamics models in Ansys CFX. Steady-state computations are performed with three different incompressible Herschel-Bulkley fluids in rough pipes with relative roughness of the inner pipe surface ε = 0.0005 – 0.01. A power-law type bath gel as a test fluid is used for experiments to validate our numerical model. The numerical results are compared with the measured values and also with numerous existing friction factor estimation models with the help of generalization of the Reynolds number in the relevant engineering range of Regen = 100 – 40,000. This paper shows that the existing approximations can not accurately describe the friction factor with pseudoplastic fluids in rough pipes. On the contrary, in the case of Bingham plastic fluid, a new, explicit calculation relation is found in a unified form accepted by the literature.
{"title":"CFD-based Estimation of Friction Factor in Rough Pipes with Herschel-Bulkley Fluids","authors":"P. Csizmadia, Gergely Dombóvári, S. Till, Martin Minkó","doi":"10.3311/ppch.20857","DOIUrl":"https://doi.org/10.3311/ppch.20857","url":null,"abstract":"The appropriate estimation of frictional losses in a pipeline system is essential. So far, little attention has been paid to determining the friction factors with non-Newtonian fluids, especially in rough pipes. This study aims at calculating the friction factor using validated three-dimensional Computational Fluid Dynamics models in Ansys CFX. Steady-state computations are performed with three different incompressible Herschel-Bulkley fluids in rough pipes with relative roughness of the inner pipe surface ε = 0.0005 – 0.01. A power-law type bath gel as a test fluid is used for experiments to validate our numerical model. The numerical results are compared with the measured values and also with numerous existing friction factor estimation models with the help of generalization of the Reynolds number in the relevant engineering range of Regen = 100 – 40,000. This paper shows that the existing approximations can not accurately describe the friction factor with pseudoplastic fluids in rough pipes. On the contrary, in the case of Bingham plastic fluid, a new, explicit calculation relation is found in a unified form accepted by the literature.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"18 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78001602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many phenomena affect devolatilization of biomass particles, including mass and heat transfer, chemical reactions and physical transformation. Mathematical models that are capable to describe pyrolysis phenomena can greatly assist the large-scale development and optimization of pyrolysis processes, but to be implemented into large-scale simulation the models need to be simplified at a certain degree. In the present study, an existing mathematical model is used to describe the pyrolysis of a single particle of biomass. It couples the heat transfer equations with the chemical kinetics equations. The common Euler explicit method is used for solving the heat transfer equation and the two-step pyrolysis kinetics equations. The model equation is solved for a sphere particle with a radius of 0.001 m and temperature ranging from 300 to 923 K. An original numerical model for the pyrolysis of agricultural biomass mixture is proposed and relevant equations solved using original program realized in MATLAB. Simplified particle model was validated with the experimental data in a non-isothermal pyrolysis reactor. The sample was heated in the temperature range of 300–923 K at average heating rates of 21, 30 and 54 K/min. The model results showed reasonable agreement with experiments. The difference (between the experimental and model results) is slightly more prominent with decreasing heating rate (21 and 30 K/min), but model results are in much better agreement with the experimental date for higher heating rate (54 K/min). It is demonstrated that a constitutive equation can be used to express devolatilization rate for higher heating rates.
{"title":"Effect of Operating Parameters on Agricultural Biomass Mixture Pyrolysis Process in a Batch Reactor","authors":"B. Miljković","doi":"10.3311/ppch.20257","DOIUrl":"https://doi.org/10.3311/ppch.20257","url":null,"abstract":"Many phenomena affect devolatilization of biomass particles, including mass and heat transfer, chemical reactions and physical transformation. Mathematical models that are capable to describe pyrolysis phenomena can greatly assist the large-scale development and optimization of pyrolysis processes, but to be implemented into large-scale simulation the models need to be simplified at a certain degree. In the present study, an existing mathematical model is used to describe the pyrolysis of a single particle of biomass. It couples the heat transfer equations with the chemical kinetics equations. The common Euler explicit method is used for solving the heat transfer equation and the two-step pyrolysis kinetics equations. The model equation is solved for a sphere particle with a radius of 0.001 m and temperature ranging from 300 to 923 K. An original numerical model for the pyrolysis of agricultural biomass mixture is proposed and relevant equations solved using original program realized in MATLAB. Simplified particle model was validated with the experimental data in a non-isothermal pyrolysis reactor. The sample was heated in the temperature range of 300–923 K at average heating rates of 21, 30 and 54 K/min. The model results showed reasonable agreement with experiments. The difference (between the experimental and model results) is slightly more prominent with decreasing heating rate (21 and 30 K/min), but model results are in much better agreement with the experimental date for higher heating rate (54 K/min). It is demonstrated that a constitutive equation can be used to express devolatilization rate for higher heating rates.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"23 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78063286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Asad A. Zaidi, S. Khan, M. Naseer, Hamad Almohammadi, Muhammad Asif, Y. Abdul Wahab, M. A. Islam, M. Johan, Hanim Hussin
Organic matter may be converted to energy through various methods, but the most preferable one is the Anaerobic Digestion (AD), specifically for biogas production. In sustainable bioenergy production, it can undoubtedly be called one of the most widely used methods from the various feedstock. Over the past years, algae waste has become an increasingly acute environmental problem but luckily it can be used as feedstock to produce bioenergy. In order to improve the energy productivity of green algae, this study is focused on the introduction of cobalt (Co) nanoparticles (NPs) in the AD process. The concentration of Co NPs was optimized using response surface methodology (RSM). Mesophilic temperature range (25–45 °C), initial pH (5–9) and Co NPs dosage (0.5–2 mg/L) were selected as the independent variables for RSM. The results indicated that at optimized values (Co NPs concentration = 1 mg/L, initial pH = 7, and digestion temperature = 35 °C) produced the highest biogas yield of 298 ml. An experiment was carried out at optimized conditions to explore the effect on biogas production. The results showed that Co NPs had a positive influence on biogas yield. The low concentrations achieved higher biogas production as compared to higher ones. A maximum biogas yield of 678 mL is achieved by Co NPs (1 mg/L). AD performance was further evaluated by the modified Gompertz model. Different kinetic parameters were calculated. The values of the performance indicators confirmed that the mathematical model fitted well with experimental data.
{"title":"Optimization of Cobalt Nanoparticles for Biogas Enhancement from Green Algae Using Response Surface Methodology","authors":"Asad A. Zaidi, S. Khan, M. Naseer, Hamad Almohammadi, Muhammad Asif, Y. Abdul Wahab, M. A. Islam, M. Johan, Hanim Hussin","doi":"10.3311/ppch.20375","DOIUrl":"https://doi.org/10.3311/ppch.20375","url":null,"abstract":"Organic matter may be converted to energy through various methods, but the most preferable one is the Anaerobic Digestion (AD), specifically for biogas production. In sustainable bioenergy production, it can undoubtedly be called one of the most widely used methods from the various feedstock. Over the past years, algae waste has become an increasingly acute environmental problem but luckily it can be used as feedstock to produce bioenergy. In order to improve the energy productivity of green algae, this study is focused on the introduction of cobalt (Co) nanoparticles (NPs) in the AD process. The concentration of Co NPs was optimized using response surface methodology (RSM). Mesophilic temperature range (25–45 °C), initial pH (5–9) and Co NPs dosage (0.5–2 mg/L) were selected as the independent variables for RSM. The results indicated that at optimized values (Co NPs concentration = 1 mg/L, initial pH = 7, and digestion temperature = 35 °C) produced the highest biogas yield of 298 ml. An experiment was carried out at optimized conditions to explore the effect on biogas production. The results showed that Co NPs had a positive influence on biogas yield. The low concentrations achieved higher biogas production as compared to higher ones. A maximum biogas yield of 678 mL is achieved by Co NPs (1 mg/L). AD performance was further evaluated by the modified Gompertz model. Different kinetic parameters were calculated. The values of the performance indicators confirmed that the mathematical model fitted well with experimental data.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"17 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87190180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Olena Khomenko, N. Sribniak, V. Ivchenko, Svitlana Hretsai, Ivan Teliushchenko, S. Halushka
This paper examines the peculiarities of the phase composition of black clinker bricks based on the ceramic masses of Kerameya enterprise (Sumy, Ukraine). The principles of charge choice are given considering the ratio of coloring oxides Fe2O3, CoO, MnO2, Mn3O4 and CuO. We found that the phase composition of black clinker bricks after firing at 1100 °С is mainly represented by quartz, microcline, mullite, residues of biotite, as well as hematite and hausmannite as the coloring phases, and also small amounts of cuprite. To produce black ceramic bricks on the basis of clay composition, we need to take 13.5 wt% elements with the ratio of Mn: Fe: Ti: Cu equal to 4.2: 7.7: 0.5: 1.1. Such ceramic mass is already used to produce ceramic clinker bricks with water absorption of 5%, mechanical compressive strength of more than 35 MPa and frost resistance of more than 150 freezing and thawing cycles.
{"title":"Peculiar Features of Formation of the Phase Composition of Black Clinker Ceramics","authors":"Olena Khomenko, N. Sribniak, V. Ivchenko, Svitlana Hretsai, Ivan Teliushchenko, S. Halushka","doi":"10.3311/ppch.21037","DOIUrl":"https://doi.org/10.3311/ppch.21037","url":null,"abstract":"This paper examines the peculiarities of the phase composition of black clinker bricks based on the ceramic masses of Kerameya enterprise (Sumy, Ukraine). The principles of charge choice are given considering the ratio of coloring oxides Fe2O3, CoO, MnO2, Mn3O4 and CuO. We found that the phase composition of black clinker bricks after firing at 1100 °С is mainly represented by quartz, microcline, mullite, residues of biotite, as well as hematite and hausmannite as the coloring phases, and also small amounts of cuprite. To produce black ceramic bricks on the basis of clay composition, we need to take 13.5 wt% elements with the ratio of Mn: Fe: Ti: Cu equal to 4.2: 7.7: 0.5: 1.1. Such ceramic mass is already used to produce ceramic clinker bricks with water absorption of 5%, mechanical compressive strength of more than 35 MPa and frost resistance of more than 150 freezing and thawing cycles.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"24 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84344450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objective of the present work was to develop an artificial neural network (ANN) model to accurately predict the dissolution profile of immediate release tablets based on non-destructive spectral data. Six different tablet formulations with varying API (caffeine) and disintegrant (potato starch) concentrations were prepared. The near-infrared (NIR) and Raman spectra of each tablet were collected in both reflection and transmission modes, then principal component analysis (PCA) was conducted. The training of the ANN was performed at each hidden neuron number from 1 to 10 in order to determine the optimal number of neurons in the hidden layer. The best results were obtained when a small number of neurons (1–3) was used. In the case of all four spectroscopic methods, the average similarity values (f2) of the optimized ANN models were above 59 for the validation tablets, indicating that the predicted dissolution profiles were similar to the measured dissolution curves. The optimized model based on reflection Raman spectra exhibited the best predictive ability. The results demonstrated the potential of ANN models in the implementation of the real-time release testing of tablet dissolution.
{"title":"Artificial Intelligence-based Prediction of In Vitro Dissolution Profile of Immediate Release Tablets with Near-infrared and Raman Spectroscopy","authors":"Orsolya Péterfi, Z. Nagy, E. Sipos, D. Galata","doi":"10.3311/ppch.20755","DOIUrl":"https://doi.org/10.3311/ppch.20755","url":null,"abstract":"The objective of the present work was to develop an artificial neural network (ANN) model to accurately predict the dissolution profile of immediate release tablets based on non-destructive spectral data. Six different tablet formulations with varying API (caffeine) and disintegrant (potato starch) concentrations were prepared. The near-infrared (NIR) and Raman spectra of each tablet were collected in both reflection and transmission modes, then principal component analysis (PCA) was conducted. The training of the ANN was performed at each hidden neuron number from 1 to 10 in order to determine the optimal number of neurons in the hidden layer. The best results were obtained when a small number of neurons (1–3) was used. In the case of all four spectroscopic methods, the average similarity values (f2) of the optimized ANN models were above 59 for the validation tablets, indicating that the predicted dissolution profiles were similar to the measured dissolution curves. The optimized model based on reflection Raman spectra exhibited the best predictive ability. The results demonstrated the potential of ANN models in the implementation of the real-time release testing of tablet dissolution.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"15 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88774927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Boukhiar, S. Benamara, Yougourthane Bouchal, Kahina Touderte, Siham Messouidi
Olive leaves (OLs) are well known for being rich in oleuropein, their main bioactive molecule which has recently been attracting great interest from the scientific community due to its antiviral properties, including Covid-19 disease. Furthermore, the high-temperature/short-time drying process has found applications for various plants and food processing, which might be also implemented for the drying of OLs. This study focuses on: 1. the mathematical modeling of thin-layer high-temperature-drying (HTD) kinetic of olive (var. Chemlal and Oleaster) leaves, and 2. the determination of HTD effect on some physicochemical properties (oleuropein, chlorophylls, and CIELab color parameters) of the dried olive leaves (DOLs). For this, four drying temperatures (100, 120, 140, and 160 °C) were applied. For comparison purposes, low-temperature DOL samples were also prepared. The obtained data have shown that among the tens tested mathematical models, the Midilli et al. model describes more correctly experimental data for all drying temperatures and for both olive leaf varieties (R2 = 0.9960, SEE = 0.0085, RMSE = 0.0165 and χ2 = 0.0006). Moreover, the results show that the HTD at 120 and 160 °C does not differ from freeze-drying in terms of oleuropein retention (p < 0.05), highlighting the technological interest in the high-temperature/short-time drying process. Considering the biological value of oleuropein, in particular its antiviral activity, the study deserves further investigation in order to elucidate certain questions such as the storability of DOLs, and their valorization as fortification ingredient in food and pharmaceutical formulations, evaluation in vitro of their biological activities, etc.
{"title":"High-temperature Thin-layer Drying Kinetic of Cultivated and Wild Algerian Olive Leaves","authors":"A. Boukhiar, S. Benamara, Yougourthane Bouchal, Kahina Touderte, Siham Messouidi","doi":"10.3311/ppch.20264","DOIUrl":"https://doi.org/10.3311/ppch.20264","url":null,"abstract":"Olive leaves (OLs) are well known for being rich in oleuropein, their main bioactive molecule which has recently been attracting great interest from the scientific community due to its antiviral properties, including Covid-19 disease. Furthermore, the high-temperature/short-time drying process has found applications for various plants and food processing, which might be also implemented for the drying of OLs. This study focuses on: 1. the mathematical modeling of thin-layer high-temperature-drying (HTD) kinetic of olive (var. Chemlal and Oleaster) leaves, and 2. the determination of HTD effect on some physicochemical properties (oleuropein, chlorophylls, and CIELab color parameters) of the dried olive leaves (DOLs). For this, four drying temperatures (100, 120, 140, and 160 °C) were applied. For comparison purposes, low-temperature DOL samples were also prepared. The obtained data have shown that among the tens tested mathematical models, the Midilli et al. model describes more correctly experimental data for all drying temperatures and for both olive leaf varieties (R2 = 0.9960, SEE = 0.0085, RMSE = 0.0165 and χ2 = 0.0006). Moreover, the results show that the HTD at 120 and 160 °C does not differ from freeze-drying in terms of oleuropein retention (p < 0.05), highlighting the technological interest in the high-temperature/short-time drying process. Considering the biological value of oleuropein, in particular its antiviral activity, the study deserves further investigation in order to elucidate certain questions such as the storability of DOLs, and their valorization as fortification ingredient in food and pharmaceutical formulations, evaluation in vitro of their biological activities, etc.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"41 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90109372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zsuzsanna Szokol, Károly Lozsi, A. Virág, A. Dancsó, L. Szlávik, G. Simig, Balázs Volk
Blarcamesine is a promising investigational drug for the treatment of Alzheimer's disease. The international nonproprietary name blarcamesine refers to a racemic compound, although it seems likely that it will be marketed in an enantiopure form. A resolution process has been described in the literature, but the absolute configurations of the enantiomers have not yet been disclosed. In the present study, crystals of (R)-(-)- and (S)-(+)-mandelate salts of (+)- and (-)-blarcamesine and also that of (R)-(+)-blarcamesine itself, suitable for single-crystal X-ray diffraction measurement were prepared and the absolute configurations of (+)- and (-)-blarcamesine have been determined.
{"title":"Assignment of Absolute Configuration to Enantiomers of Anti-Alzheimer Drug Candidate Blarcamesine","authors":"Zsuzsanna Szokol, Károly Lozsi, A. Virág, A. Dancsó, L. Szlávik, G. Simig, Balázs Volk","doi":"10.3311/ppch.20662","DOIUrl":"https://doi.org/10.3311/ppch.20662","url":null,"abstract":"Blarcamesine is a promising investigational drug for the treatment of Alzheimer's disease. The international nonproprietary name blarcamesine refers to a racemic compound, although it seems likely that it will be marketed in an enantiopure form. A resolution process has been described in the literature, but the absolute configurations of the enantiomers have not yet been disclosed. In the present study, crystals of (R)-(-)- and (S)-(+)-mandelate salts of (+)- and (-)-blarcamesine and also that of (R)-(+)-blarcamesine itself, suitable for single-crystal X-ray diffraction measurement were prepared and the absolute configurations of (+)- and (-)-blarcamesine have been determined.","PeriodicalId":19922,"journal":{"name":"Periodica Polytechnica Chemical Engineering","volume":"7 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78674631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}