M. Radonjic, J. Petrovic, M. Milivojevic, M. Stevanović, Jasmina Stojkovska, B. Obradovic
A multidisciplinary approach based on experiments and mathematical modeling was used in biomimetic system development for three-dimensional (3D) cultures of cancer cells. Specifically, two cancer cell lines, human embryonic teratocarcinoma NT2/D1 and rat glioma C6, were immobilized in alginate microbeads and microfibers, respectively, and cultured under static and flow conditions in perfusion bioreactors, while chemical engineering methods were applied to explain the obtained results. The superficial medium velocity of 80 mm s-1 induced lower viability of NT2/D1 cells in superficial microbead zones implying adverse effects of fluid shear stresses estimated as ~67 mPa. On the contrary, similar velocity (100 mm s-1) enhanced proliferation of C6 glioma cells within microfibers as compared to static controls. An additional study of silver release from nanocomposite Ag/honey/alginate microfibers under perfusion indicated that medium partially flows through the hydrogel (interstitial velocity of ~10 nm s-1). Thus, a diffusion-advection-reaction model was applied to describe the mass transport to immobilized cells within microfibers. Substances with diffusion coefficients of ?10-9-10-11 m2 s-1 are sufficiently supplied by diffusion only, while those with significantly lower diffusivities (?10-19 m2 s-1) require additional convective transport. The present study demonstrates the selection and contribution of chemical engineering methods in tumor model system development.
基于实验和数学建模的多学科方法被用于癌细胞三维(3D)培养的仿生系统开发。具体而言，将人胚胎畸胎癌NT2/D1和大鼠胶质瘤C6两种癌细胞分别固定在海藻酸微珠和微纤维中，在灌注生物反应器中静态和流动条件下培养，并应用化学工程方法解释所得结果。表面介质流速为80 mm s-1时，表面微珠区NT2/D1细胞活力降低，表明流体剪切应力的不利影响约为~67 mPa。相反，与静态对照相比，相似的速度(100 mm s-1)增强了微纤维内C6胶质瘤细胞的增殖。另外对银/蜂蜜/海藻酸盐纳米复合微纤维在灌注下的银释放进行了研究，发现介质部分流过水凝胶(间隙速度为~10 nm s-1)。因此，采用扩散-平流-反应模型来描述物质在微纤维内向固定细胞的转移。扩散系数为- 10-9-10-11 m2 s-1的物质仅由扩散供给，而扩散系数明显较低的物质(?10-19 m2 s-1)需要额外的对流输送。本研究展示了化学工程方法在肿瘤模型系统开发中的选择和贡献。
{"title":"Chemical engineering methods in analyses of 3D cancer cell cultures: Hydrodinamic and mass transport considerations","authors":"M. Radonjic, J. Petrovic, M. Milivojevic, M. Stevanović, Jasmina Stojkovska, B. Obradovic","doi":"10.2298/ciceq210607033r","DOIUrl":"https://doi.org/10.2298/ciceq210607033r","url":null,"abstract":"A multidisciplinary approach based on experiments and mathematical modeling was used in biomimetic system development for three-dimensional (3D) cultures of cancer cells. Specifically, two cancer cell lines, human embryonic teratocarcinoma NT2/D1 and rat glioma C6, were immobilized in alginate microbeads and microfibers, respectively, and cultured under static and flow conditions in perfusion bioreactors, while chemical engineering methods were applied to explain the obtained results. The superficial medium velocity of 80 mm s-1 induced lower viability of NT2/D1 cells in superficial microbead zones implying adverse effects of fluid shear stresses estimated as ~67 mPa. On the contrary, similar velocity (100 mm s-1) enhanced proliferation of C6 glioma cells within microfibers as compared to static controls. An additional study of silver release from nanocomposite Ag/honey/alginate microfibers under perfusion indicated that medium partially flows through the hydrogel (interstitial velocity of ~10 nm s-1). Thus, a diffusion-advection-reaction model was applied to describe the mass transport to immobilized cells within microfibers. Substances with diffusion coefficients of ?10-9-10-11 m2 s-1 are sufficiently supplied by diffusion only, while those with significantly lower diffusivities (?10-19 m2 s-1) require additional convective transport. The present study demonstrates the selection and contribution of chemical engineering methods in tumor model system development.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68462420","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}
R. Ouafi, A. Omor, Y. Gaga, M. Akhazzane, M. Taleb, Z. Rais
This research investigates the adsorption potential of pine cones powder (PCP) for the removal of copper ions (Cu(II)) from aqueous solutions. The process of adsorption was reasonably fast to be completed within a time of 60 min. The pseudo-second order kinetic model describes properly the Cu(II) adsorption by PCP. The adsorbent was characterised by various instrumental techniques and batch experiments were conducted to investigate the effect of PCP dose, solution pH, particle size and initial Cu(II) concentration on adsorption efficiency. Optimum Cu(II) removal occurred at a slightly acidic pH, with a particle size less than 100 ?m. The effective PCP dose was estimated to be 36 g.L-1. The increase in the initial concentration of Cu (II) was accompanied by a reduction in the rate of its reduction by almost half. The Langmuir model was the best fitting isotherm with a maximum adsorption capacity of 9.08 mg.g-1. The thermodynamic parameters values showed that the Cu(II) adsorption was a spontaneous and endothermic process. The results of this research suggest that Cu(II) could be removed through an environmentally friendly process using PCP as low-cost natural wastes.
{"title":"Pine cones powder for the adsorptive removal of copper ions from water","authors":"R. Ouafi, A. Omor, Y. Gaga, M. Akhazzane, M. Taleb, Z. Rais","doi":"10.2298/CICEQ200101001O","DOIUrl":"https://doi.org/10.2298/CICEQ200101001O","url":null,"abstract":"This research investigates the adsorption potential of pine cones powder (PCP) for the removal of copper ions (Cu(II)) from aqueous solutions. The process of adsorption was reasonably fast to be completed within a time of 60 min. The pseudo-second order kinetic model describes properly the Cu(II) adsorption by PCP. The adsorbent was characterised by various instrumental techniques and batch experiments were conducted to investigate the effect of PCP dose, solution pH, particle size and initial Cu(II) concentration on adsorption efficiency. Optimum Cu(II) removal occurred at a slightly acidic pH, with a particle size less than 100 ?m. The effective PCP dose was estimated to be 36 g.L-1. The increase in the initial concentration of Cu (II) was accompanied by a reduction in the rate of its reduction by almost half. The Langmuir model was the best fitting isotherm with a maximum adsorption capacity of 9.08 mg.g-1. The thermodynamic parameters values showed that the Cu(II) adsorption was a spontaneous and endothermic process. The results of this research suggest that Cu(II) could be removed through an environmentally friendly process using PCP as low-cost natural wastes.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68460435","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 study is to determine the thermophysical property variations (such as viscosity, density, specific heat capacity and thermal conductivity) of graphene suspended base fluid (ethylene glycol (EG)/water (W)), with respect to graphene nanoparticle concentration and hot fluid inlet temperature. Graphene nanoparticle concentrations (0.2, 0.4, 0.6, 0.8 and 1 vol.%) and the base fluid of 30:70 vol.% of EG: Water is prepared initially. The impact of graphene nanoparticle addition on base fluids based on experimentation in the commercial plate heat exchanger was studied. In this experiment, the hot fluid inlet temperature was varied at 55, 65 and 75 ?C. The experimental results of thermophysical properties were compared with the selected models proposed in the literature. Einstein (1956), Kitano (1981) and Bachelor models (1977) have been used to consider the effect of viscosity. The measured density and specific heat capacity were validated with Pak and Cho and Xuan models, respectively. To consider the effect of thermal conductivity, three different models (Maxwell (1954), Vajjah (2010) and Sahoo (2012)) have been used. Study revealed that the thermophysical properties of base fluid significantly affect the graphene nanoparticle suspension.
{"title":"Studies on thermophysical property variations of graphene nanoparticle suspended ethylene glycol/water","authors":"M. P. Srinivasan, R. Baskar","doi":"10.2298/ciceq200504036p","DOIUrl":"https://doi.org/10.2298/ciceq200504036p","url":null,"abstract":"The objective of the study is to determine the thermophysical property variations (such as viscosity, density, specific heat capacity and thermal conductivity) of graphene suspended base fluid (ethylene glycol (EG)/water (W)), with respect to graphene nanoparticle concentration and hot fluid inlet temperature. Graphene nanoparticle concentrations (0.2, 0.4, 0.6, 0.8 and 1 vol.%) and the base fluid of 30:70 vol.% of EG: Water is prepared initially. The impact of graphene nanoparticle addition on base fluids based on experimentation in the commercial plate heat exchanger was studied. In this experiment, the hot fluid inlet temperature was varied at 55, 65 and 75 ?C. The experimental results of thermophysical properties were compared with the selected models proposed in the literature. Einstein (1956), Kitano (1981) and Bachelor models (1977) have been used to consider the effect of viscosity. The measured density and specific heat capacity were validated with Pak and Cho and Xuan models, respectively. To consider the effect of thermal conductivity, three different models (Maxwell (1954), Vajjah (2010) and Sahoo (2012)) have been used. Study revealed that the thermophysical properties of base fluid significantly affect the graphene nanoparticle suspension.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68460510","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}
Pervaporation is a membrane process that offers high separation performance and has an important potential for the treatment of saline water sources. In this study, poly(vinyl alcohol) (PVA) and PVA-SiO2 nanocomposite membranes were prepared by the solution-casting method, and pervaporative water desalination studies were carried out for synthetic seawater (35 g L-1) at 30, 40 and 50?C. Effects of the temperatures and the incorporation of SiO2 on the pervaporation performance of polymeric nanocomposite membranes were investigated. Membranes were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). In experiments conducted at 50?C, a permeate flux of 4.93 kg m-2 h-1 with a salt rejection of 99.3% were obtained. The highest salt rejection was 99.8% at temperature of 30?C. The results showed that the pervaporation performance of PVA membranes was remarkably enhanced with the incorporation of nano-SiO2 into polymeric matrix.
渗透蒸发是一种膜工艺，具有很高的分离性能，在处理含盐水源方面具有重要的潜力。本研究采用溶液浇铸法制备了聚乙烯醇(PVA)和PVA- sio2纳米复合膜，并对合成海水(35 g L-1)在30、40和50℃条件下进行了渗透脱盐研究。研究了温度和SiO2掺入量对聚合物纳米复合膜渗透汽化性能的影响。采用扫描电镜(SEM)、傅里叶变换红外光谱(FT-IR)和热重分析(TGA)对膜进行了表征。在50?C的渗透通量为4.93 kg m-2 h-1，盐去除率为99.3%。在温度为30℃时，最高的脱盐率为99.8%。结果表明，在聚合物基体中掺入纳米sio2后，PVA膜的渗透汽化性能得到了显著提高。
{"title":"Preparation and characterization of PVA-SiO2 nanocomposite membranes for seawater desalination by pervaporation","authors":"B. Tirnakci, Y. Salt","doi":"10.2298/ciceq200505037t","DOIUrl":"https://doi.org/10.2298/ciceq200505037t","url":null,"abstract":"Pervaporation is a membrane process that offers high separation performance and has an important potential for the treatment of saline water sources. In this study, poly(vinyl alcohol) (PVA) and PVA-SiO2 nanocomposite membranes were prepared by the solution-casting method, and pervaporative water desalination studies were carried out for synthetic seawater (35 g L-1) at 30, 40 and 50?C. Effects of the temperatures and the incorporation of SiO2 on the pervaporation performance of polymeric nanocomposite membranes were investigated. Membranes were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). In experiments conducted at 50?C, a permeate flux of 4.93 kg m-2 h-1 with a salt rejection of 99.3% were obtained. The highest salt rejection was 99.8% at temperature of 30?C. The results showed that the pervaporation performance of PVA membranes was remarkably enhanced with the incorporation of nano-SiO2 into polymeric matrix.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68460520","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. Janjatović, C. Eric, D. Rajnović, S. Baloš, V. Grabulov, L. Šidjanin
Dual phase ADI material microstructure consists of different amounts and morphologies of ausferrite and free ferrite, obtained by subjecting ductile iron to specific heat treatment. As such, its strength is lower compared to comparable ADI materials, but exhibiting a higher ductility, the major disadvantage of ADI. In the current study, an unalloyed ductile iron was intercritical austenitised in two-phase regions (?+?) at four temperatures from 840 to 780?C for 2 hours and austempered at 400?C for 1 hour to obtain dual phase ADI with different percentages of free ferrite and ausferrite. Metallographic and fracture studies were performed by light and scanning electron microscopy, respectively. Microscopy results were correlated to tensile testing results. The results indicated that, as the amount of ausferrite present in the matrix increases, higher values of strength and lower ductility are obtained. The fracture surfaces of dual phase ADI microstructures with 22.8% of ausferrite in their matrix have regions of quasi-cleavage fracture around last-to-freeze zones, related to the presence of ausferrite in those areas. The specimens with the highest values of ausferrite of 86.8% among the dual phase microstructure have a dominant quasi-cleavage type of fracture.
{"title":"Microstructure and fracture mode of unalloyed dual phase austempered ductile iron","authors":"P. Janjatović, C. Eric, D. Rajnović, S. Baloš, V. Grabulov, L. Šidjanin","doi":"10.2298/ciceq201222027j","DOIUrl":"https://doi.org/10.2298/ciceq201222027j","url":null,"abstract":"Dual phase ADI material microstructure consists of different amounts and morphologies of ausferrite and free ferrite, obtained by subjecting ductile iron to specific heat treatment. As such, its strength is lower compared to comparable ADI materials, but exhibiting a higher ductility, the major disadvantage of ADI. In the current study, an unalloyed ductile iron was intercritical austenitised in two-phase regions (?+?) at four temperatures from 840 to 780?C for 2 hours and austempered at 400?C for 1 hour to obtain dual phase ADI with different percentages of free ferrite and ausferrite. Metallographic and fracture studies were performed by light and scanning electron microscopy, respectively. Microscopy results were correlated to tensile testing results. The results indicated that, as the amount of ausferrite present in the matrix increases, higher values of strength and lower ductility are obtained. The fracture surfaces of dual phase ADI microstructures with 22.8% of ausferrite in their matrix have regions of quasi-cleavage fracture around last-to-freeze zones, related to the presence of ausferrite in those areas. The specimens with the highest values of ausferrite of 86.8% among the dual phase microstructure have a dominant quasi-cleavage type of fracture.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68461541","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}
In this article, thermal stability, viscosity, density and surface tension of Graphene nano-platelets dispersed sunflower oil are experimentally determined by varying the Graphene concentration (0.1-1.1wt%) and temperature (40-100?C). The SEM micrograph and the EDS spectra are used to characterize the Graphene. Nanofluids are prepared by ultrasonication technique (two-step method) and the maximum thermal stability of about 280?C is achieved at 1.1wt% Graphene nanofluids. The dynamic viscosity diminished in an exponential shape in acquiescence with Arrhenius equation and the densities of samples are characteristic with linear decrement in the estimated temperature range. Density and surface tension increases with the Graphene concentration, while a reverse trend is observed with temperature rise. The maximum thermal stability, viscosity, density and surface tension is obtained in the nanofluid with 1.1 wt% concentration and the minimum is obtained in the nanofluid with 0.1 wt% concentration.
{"title":"Influence of graphene nano-platelets dispersion on the thermo-physical properties of sunflower oil","authors":"J. Bensam, M. Muthuraj","doi":"10.2298/CICEQ210101018B","DOIUrl":"https://doi.org/10.2298/CICEQ210101018B","url":null,"abstract":"In this article, thermal stability, viscosity, density and surface tension of Graphene nano-platelets dispersed sunflower oil are experimentally determined by varying the Graphene concentration (0.1-1.1wt%) and temperature (40-100?C). The SEM micrograph and the EDS spectra are used to characterize the Graphene. Nanofluids are prepared by ultrasonication technique (two-step method) and the maximum thermal stability of about 280?C is achieved at 1.1wt% Graphene nanofluids. The dynamic viscosity diminished in an exponential shape in acquiescence with Arrhenius equation and the densities of samples are characteristic with linear decrement in the estimated temperature range. Density and surface tension increases with the Graphene concentration, while a reverse trend is observed with temperature rise. The maximum thermal stability, viscosity, density and surface tension is obtained in the nanofluid with 1.1 wt% concentration and the minimum is obtained in the nanofluid with 0.1 wt% concentration.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68461609","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}
Bruna Pratto, Martha Suzana Rodrigues dos Santos-Rocha, Gustavo E. A. P. A. Batista, I. Cavalcanti-Montaño, Carlos Alberto Suarez Galeano, Antonio José Gonçalves da Cruz, R. de Sousa
Bioreactors operating in fed-batch mode improve the enzymatic hydrolysis productivity at high biomass loadings. The present work aimed to apply rational feeding strategies of substrates (pretreated sugarcane straw) and enzymes (CellicCtec2?) to achieve sugar titers at industrial levels. The instantaneous substrate concentration was kept constant at 5 % (w/v) along the fed-batch, and the enzyme dosage inside the bioreactor was adjusted so that the reaction rate was not less than a pre-defined value (a percentage of the initial reaction rate - rmin). When r reached values below rmin, enzyme pulses were applied to return the reaction rate to its initial value (r0). The optimized feeding policy indicated a reaction rate maintained at a minimum of 70 % of r0, based on the trade-off between glucose productivity and enzyme saving. Initially, it was possible to process a total of 21 % (w/v) solid load, achieving 160 g/L of glucose concentration and 80 % of glucose yield. It was verified that non-productive enzyme adsorption was the main reason for some reduction of hydrolysis yield regarding the theoretical cellulose-to-glucose conversion. An increment of 30 g/L in the final glucose concentration was achieved when a lignin-blocking additive (soybean protein) was used in the enzymatic hydrolysis.
{"title":"Rational feeding strategies of substrate and enzymes to enzymatic hydrolysis bioreactors","authors":"Bruna Pratto, Martha Suzana Rodrigues dos Santos-Rocha, Gustavo E. A. P. A. Batista, I. Cavalcanti-Montaño, Carlos Alberto Suarez Galeano, Antonio José Gonçalves da Cruz, R. de Sousa","doi":"10.2298/ciceq201202030p","DOIUrl":"https://doi.org/10.2298/ciceq201202030p","url":null,"abstract":"Bioreactors operating in fed-batch mode improve the enzymatic hydrolysis productivity at high biomass loadings. The present work aimed to apply rational feeding strategies of substrates (pretreated sugarcane straw) and enzymes (CellicCtec2?) to achieve sugar titers at industrial levels. The instantaneous substrate concentration was kept constant at 5 % (w/v) along the fed-batch, and the enzyme dosage inside the bioreactor was adjusted so that the reaction rate was not less than a pre-defined value (a percentage of the initial reaction rate - rmin). When r reached values below rmin, enzyme pulses were applied to return the reaction rate to its initial value (r0). The optimized feeding policy indicated a reaction rate maintained at a minimum of 70 % of r0, based on the trade-off between glucose productivity and enzyme saving. Initially, it was possible to process a total of 21 % (w/v) solid load, achieving 160 g/L of glucose concentration and 80 % of glucose yield. It was verified that non-productive enzyme adsorption was the main reason for some reduction of hydrolysis yield regarding the theoretical cellulose-to-glucose conversion. An increment of 30 g/L in the final glucose concentration was achieved when a lignin-blocking additive (soybean protein) was used in the enzymatic hydrolysis.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68461986","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 present paper employs supported ruthenium nanoparticles alongside catalytic quantities of the radical initiator, which are proven to be capable of cyclooctene oxidation with green conditions, in the absence of solvent, with air as the main oxidant and without sacrificial reductant. The paper examines the effects of a range of radical initiators and how the products are distributed over time. Furthermore, the paper addresses the reaction pathways to the epoxides and allylic alcohol, the latter being the primary by-product, whilst also analysing the impact of the technique of synthesis, reaction time, and various supports. Catalyst activity can be markedly improved by adopting a sol-immobilization technique to synthesise the catalysts, with retention of selectivity to the epoxide.
{"title":"Oxidation of cycloalkene using supported ruthenium catalysts under solvent-free conditions","authors":"Raiedhah Alsaiari Abdullah","doi":"10.2298/CICEQ210304020A","DOIUrl":"https://doi.org/10.2298/CICEQ210304020A","url":null,"abstract":"The present paper employs supported ruthenium nanoparticles alongside catalytic quantities of the radical initiator, which are proven to be capable of cyclooctene oxidation with green conditions, in the absence of solvent, with air as the main oxidant and without sacrificial reductant. The paper examines the effects of a range of radical initiators and how the products are distributed over time. Furthermore, the paper addresses the reaction pathways to the epoxides and allylic alcohol, the latter being the primary by-product, whilst also analysing the impact of the technique of synthesis, reaction time, and various supports. Catalyst activity can be markedly improved by adopting a sol-immobilization technique to synthesise the catalysts, with retention of selectivity to the epoxide.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"18 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68462063","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}
Marija B. Tasic, M. Stanković, Milan Kostic, Olivera S. Stamenković, V. Veljković
Apple pomace is a solid waste derived from the apple processing industry. To foster sustainability, the apple processing industry must implement the circular economy model of biorefinery and treat apple pomace as a valuable source of apple seed oil. The first time, this study dealt with the design, economic, and potential environmental impact assessment of biodiesel production using apple pomace as a source of apple seed oil. An Aspen Plus? and WAR? software were used to evaluate the designed biodiesel production. Supercritical CO2 extraction and methanolysis of apple seed oil, methanol recovery, and biodiesel separation were the main production steps. The production facility was assumed to process 24 tons of apple seeds daily. The total capital and production costs were 1.26 US$ million and 2.82 US$ million, respectively. If revenues from selling apple seed meal as cattle feed were included, a biodiesel price could be 0.39 US$/kg. The process was environmentally friendly when apple seed meal was not treated as waste.
{"title":"Circular economy in apple processing industry: Biodiesel production from waste apple seeds","authors":"Marija B. Tasic, M. Stanković, Milan Kostic, Olivera S. Stamenković, V. Veljković","doi":"10.2298/ciceq210819035t","DOIUrl":"https://doi.org/10.2298/ciceq210819035t","url":null,"abstract":"Apple pomace is a solid waste derived from the apple processing industry. To foster sustainability, the apple processing industry must implement the circular economy model of biorefinery and treat apple pomace as a valuable source of apple seed oil. The first time, this study dealt with the design, economic, and potential environmental impact assessment of biodiesel production using apple pomace as a source of apple seed oil. An Aspen Plus? and WAR? software were used to evaluate the designed biodiesel production. Supercritical CO2 extraction and methanolysis of apple seed oil, methanol recovery, and biodiesel separation were the main production steps. The production facility was assumed to process 24 tons of apple seeds daily. The total capital and production costs were 1.26 US$ million and 2.82 US$ million, respectively. If revenues from selling apple seed meal as cattle feed were included, a biodiesel price could be 0.39 US$/kg. The process was environmentally friendly when apple seed meal was not treated as waste.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68462503","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. Ashmawy, El-Sayed Elnaggar, M. Mohamed, Mohamed Hamam
The deposition of paraffin wax from crude oil at low temperatures due to wax deposition, high pour point, high viscosity, and weak flow capability is among the critical and persisting challenges faced by the petroleum industry. In this study, a new para-decyloxy allyl benzoate (I10) was prepared, polymerized into HI10, and copolymerized with dioctadecyl maleate into MHI10 via the free-radical polymerization method employing azobisisobutyronitrile and toluene as the initiator and solvent, respectively. The prepared monomer was characterized by spectroscopic analyses (Fourier-transform infrared (FT-IR)) and proton nuclear magnetic resonance. Further, the polymers were characterized by FT-IR, and their average molecular weights were determined by gel permeation chromatography. The prepared compounds were taken in different concentrations and then tested as flow improvers of Qarun waxy crude oil using pour point depression and rheological parameters. The results of this test indicated that MHI10 exerted the highest effect on pour point reduction and the rheological parameters (yield value and apparent viscosity). Moreover, an increase in the efficiency of the additives was observed after increasing their concentration from 1000 to 5000 ppm.
{"title":"Novel allyl-ester-based polymers as flow improvers for waxy crude oil","authors":"A. Ashmawy, El-Sayed Elnaggar, M. Mohamed, Mohamed Hamam","doi":"10.2298/CICEQ201011008A","DOIUrl":"https://doi.org/10.2298/CICEQ201011008A","url":null,"abstract":"The deposition of paraffin wax from crude oil at low temperatures due to wax deposition, high pour point, high viscosity, and weak flow capability is among the critical and persisting challenges faced by the petroleum industry. In this study, a new para-decyloxy allyl benzoate (I10) was prepared, polymerized into HI10, and copolymerized with dioctadecyl maleate into MHI10 via the free-radical polymerization method employing azobisisobutyronitrile and toluene as the initiator and solvent, respectively. The prepared monomer was characterized by spectroscopic analyses (Fourier-transform infrared (FT-IR)) and proton nuclear magnetic resonance. Further, the polymers were characterized by FT-IR, and their average molecular weights were determined by gel permeation chromatography. The prepared compounds were taken in different concentrations and then tested as flow improvers of Qarun waxy crude oil using pour point depression and rheological parameters. The results of this test indicated that MHI10 exerted the highest effect on pour point reduction and the rheological parameters (yield value and apparent viscosity). Moreover, an increase in the efficiency of the additives was observed after increasing their concentration from 1000 to 5000 ppm.","PeriodicalId":9716,"journal":{"name":"Chemical Industry & Chemical Engineering Quarterly","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68461041","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}
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