Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104023
Ya-Yuan He, Zhaozeng Chen, Hai-bin Qu, Xingchu Gong
Alkaloids have a variety of bioactivities and great development value in the fields of pharmaceuticals, cosmetics and health food. Column chromatography is a common method for preparing alkaloids. In this paper, the research status of the separation and purification of alkaloids from Chinese medicines by column chromatography is reviewed, and the factors that influence the refining of alkaloids via a macroporous adsorption resin, ion exchange resin and silica gel are summarized. The thermodynamic and kinetic modeling methods for the static adsorption of adsorbents are also reviewed in this paper. It is suggested that the modeling method of the column chromatography process be deeply studied to establish a more stringent quality control method for sampling liquid and to strengthen the online detection of the chromatography process to improve the refining effect of alkaloids.
{"title":"Research Progress on the Separation of Alkaloids from Chinese Medicines by Column Chromatography","authors":"Ya-Yuan He, Zhaozeng Chen, Hai-bin Qu, Xingchu Gong","doi":"10.4236/aces.2020.104023","DOIUrl":"https://doi.org/10.4236/aces.2020.104023","url":null,"abstract":"Alkaloids have a variety of bioactivities and great development value in the fields of pharmaceuticals, cosmetics and health food. Column chromatography is a common method for preparing alkaloids. In this paper, the research status of the separation and purification of alkaloids from Chinese medicines by column chromatography is reviewed, and the factors that influence the refining of alkaloids via a macroporous adsorption resin, ion exchange resin and silica gel are summarized. The thermodynamic and kinetic modeling methods for the static adsorption of adsorbents are also reviewed in this paper. It is suggested that the modeling method of the column chromatography process be deeply studied to establish a more stringent quality control method for sampling liquid and to strengthen the online detection of the chromatography process to improve the refining effect of alkaloids.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"57 1","pages":"358-377"},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82017138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104026
Emiowele Preye, J. G. Akpa, P. Ikenyiri
The simulation of a 270 KTA capacity polyethylene plant was performed using Aspen Hysys version 8.8. A Hysys model of the polyethylene was developed using the polyethylene plant layout of Indorama Eleme Petrochemical Company. A material and energy balance for the various components of the plant was performed manually and with Hysys for comparison. The design of the various components of the Hysys model was performed. The polyethylene reactor was simulated to study the effect of process functional parameters such as reactor dimensions, temperature and pressure. The effect of reactor size and number on polyethylene output was studied by simulating the plant with five continuous stirred tank reactors (CSTRs) in series and a single reactor. The results of the material and energy balance of the various components of the plant were performed manually and with Hysys which showed a maximum deviation of 0.8%. The design results of the sizing parameters for the Multiple and single CSTRs were compared in terms of Volume, Diameter, Height, Spacetime, Space Velocity, and Volumetric flowrate respectively. At 90% Conversion, the multiple CSTRs gave 600 dm3, 0.7668 m, 1.198 m, 0.052 hr, 195.83 hr-1, and 117.5 m3/h for the above listed parameters, while the single CSTR gave 6000 dm3, 1.721 m, 2.581 m, 0.056 hr, 17.867 hr-1 and 107.2 m3/h for the same conversion. The sizing results for each of the five compressors were also compared in terms of the following parameters: Adiabatic Head, Polytropic Head, Adiabatic fluid Head, polytropic Fluid Head, Adiabatic Efficiency, power consumed, polytropic head factor, polytropic exponent and isentropic exponent. The effect of reactor size and number showed that At 90% conversion the multiple CSTRS in series gave a lower volume than the single CSTR for the same conversion, and more Economical than the single CSTR for the same conversion.
{"title":"Simulation of a Plant for the Production of Polyethylene","authors":"Emiowele Preye, J. G. Akpa, P. Ikenyiri","doi":"10.4236/aces.2020.104026","DOIUrl":"https://doi.org/10.4236/aces.2020.104026","url":null,"abstract":"The simulation of a 270 KTA capacity polyethylene plant was performed using Aspen Hysys version 8.8. A Hysys model of the polyethylene was developed using the polyethylene plant layout of Indorama Eleme Petrochemical Company. A material and energy balance for the various components of the plant was performed manually and with Hysys for comparison. The design of the various components of the Hysys model was performed. The polyethylene reactor was simulated to study the effect of process functional parameters such as reactor dimensions, temperature and pressure. The effect of reactor size and number on polyethylene output was studied by simulating the plant with five continuous stirred tank reactors (CSTRs) in series and a single reactor. The results of the material and energy balance of the various components of the plant were performed manually and with Hysys which showed a maximum deviation of 0.8%. The design results of the sizing parameters for the Multiple and single CSTRs were compared in terms of Volume, Diameter, Height, Spacetime, Space Velocity, and Volumetric flowrate respectively. At 90% Conversion, the multiple CSTRs gave 600 dm3, 0.7668 m, 1.198 m, 0.052 hr, 195.83 hr-1, and 117.5 m3/h for the above listed parameters, while the single CSTR gave 6000 dm3, 1.721 m, 2.581 m, 0.056 hr, 17.867 hr-1 and 107.2 m3/h for the same conversion. The sizing results for each of the five compressors were also compared in terms of the following parameters: Adiabatic Head, Polytropic Head, Adiabatic fluid Head, polytropic Fluid Head, Adiabatic Efficiency, power consumed, polytropic head factor, polytropic exponent and isentropic exponent. The effect of reactor size and number showed that At 90% conversion the multiple CSTRS in series gave a lower volume than the single CSTR for the same conversion, and more Economical than the single CSTR for the same conversion.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"83 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78381218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104018
M. A. Salam, T. Hossain, N. Papri, K. Ahmed, M. S. Habib, M. S. Uddin, R. Wilckens
The review outcome represents the optimum catalytic conditions for the production of hydrogen using hydrotalcite derived catalysts. It covers dry and steam reforming of methane, steam reforming of methanol and ethanol to hydrogen. The review also revealed the specific properties of hydrotalcite derived catalysts for the reactions. Among catalyst investigated, Ni & Fe promoted Al-Mg containing hydrotalcite catalyst perform best (99%) for dry reforming of methane at 250°C. For steam methane reforming, Ni containing ca-aluminates hydrotalcite catalyst act as the best (99%) at 550°C. Cu-supported Zn-Al-containing catalyst performs the best (99.98%) for steam reforming of methanol at 300°C whereas Cu impregnated Mg-Al containing hydrotalcite is the best (99%) for steam reforming of ethanol at 200°C - 600°C. It’s (HT°) tunable and versatile textural and morphological properties showed excellent catalytic performances for different industrial processes and in sustainable hydrogen production.
{"title":"Hydrogen Production Performances via Steam Reforming over Hydrotalcite Derived Catalyst: A Sustainable Energy Production Review","authors":"M. A. Salam, T. Hossain, N. Papri, K. Ahmed, M. S. Habib, M. S. Uddin, R. Wilckens","doi":"10.4236/aces.2020.104018","DOIUrl":"https://doi.org/10.4236/aces.2020.104018","url":null,"abstract":"The review outcome represents the optimum catalytic conditions for the production of hydrogen using hydrotalcite derived catalysts. It covers dry and steam reforming of methane, steam reforming of methanol and ethanol to hydrogen. The review also revealed the specific properties of hydrotalcite derived catalysts for the reactions. Among catalyst investigated, Ni & Fe promoted Al-Mg containing hydrotalcite catalyst perform best (99%) for dry reforming of methane at 250°C. For steam methane reforming, Ni containing ca-aluminates hydrotalcite catalyst act as the best (99%) at 550°C. Cu-supported Zn-Al-containing catalyst performs the best (99.98%) for steam reforming of methanol at 300°C whereas Cu impregnated Mg-Al containing hydrotalcite is the best (99%) for steam reforming of ethanol at 200°C - 600°C. It’s (HT°) tunable and versatile textural and morphological properties showed excellent catalytic performances for different industrial processes and in sustainable hydrogen production.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75028250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104019
Lawrence Leelabari Pemii, K. Dagde, T. O. Goodhead
Gas flaring is concerned with the combustion of lighter ends of hydrocarbon mostly produced in association with crude oil. Flare networks are designed to handle the gas volume required to be flared. Most times, this flare networks are in close proximity but still have independent flare stacks, increasing risk to environment and cost on infrastructures. There is a need to integrate the flare networks in facilities within same area and through the application of Pinch Analysis concept, the resultant flare network can be optimized to give a system having optimal tail and header pipe sizes that will reduce cost and impact on environment. In the light of the foregoing, the concept of pinch analysis was used in debottlenecking integrated gas flare networks from a flow station and a refinery in close proximity. Both flare networks were integrated and the resultant gas flare network was optimized to obtain the optimum pipe header and tail pipe sizes with the capacity to withstand the inventory from both facilities and satisfy the set constraints such as Mach number, noise, RhoV2 and backpressure. Mach number was set at 0.7 for tail pipes and 0.5 for header pipes, noise limit was not to exceed 80 dB upstream and 115 dB downstream the sources, RhoV2 was limited to 6000 kg/m/s2 and the back pressure requirement was source dependent respectively. The fire case scenario was considered, as it is the worst-case scenario in the studies. When pinch analysis was applied in debottlenecking the combined gas flare network, it gave smaller tail and header pipe sizes which is more economical. A 20% decrease in pipe sizes was recorded at the end of the study.
{"title":"Gas Flare Design Debottlenecking Using Pinch Analysis","authors":"Lawrence Leelabari Pemii, K. Dagde, T. O. Goodhead","doi":"10.4236/aces.2020.104019","DOIUrl":"https://doi.org/10.4236/aces.2020.104019","url":null,"abstract":"Gas flaring is concerned with the combustion of lighter ends of \u0000hydrocarbon mostly produced in association with crude oil. Flare networks are \u0000designed to handle the gas volume required to be flared. Most times, this flare \u0000networks are in close proximity but still have independent flare stacks, increasing \u0000risk to environment and cost on infrastructures. There is a need to integrate \u0000the flare networks in facilities within same area and through the application \u0000of Pinch Analysis concept, the resultant flare network can be optimized to give \u0000a system having optimal tail and header pipe sizes that will reduce cost and \u0000impact on environment. In the light of the \u0000foregoing, the concept of pinch analysis \u0000was used in debottlenecking integrated gas flare networks from a flow \u0000station and a refinery in close proximity. Both flare networks were integrated \u0000and the resultant gas flare network was optimized to obtain the optimum pipe \u0000header and tail pipe sizes with the capacity to withstand the inventory from \u0000both facilities and satisfy the set constraints such as Mach number, noise, \u0000RhoV2 and backpressure. Mach number was set at 0.7 for tail pipes \u0000and 0.5 for header pipes, noise limit was not to exceed 80 dB upstream and 115 dB \u0000downstream the sources, RhoV2 was limited to 6000 kg/m/s2 and the back pressure requirement was source \u0000dependent respectively. The fire case scenario was considered, as it is the \u0000worst-case scenario in the studies. When pinch analysis was applied in \u0000debottlenecking the combined gas flare network, it gave smaller tail and header pipe sizes which is more economical. A 20% \u0000decrease in pipe sizes was recorded at the end of the study.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84268755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104025
Victor Peter Maciver, K. Dagde, J. Konne
This work describes the development of a process to produce zeolite X from mined kaolin clay from Kono-Boue and Chokocho, Rivers State, Nigeria. The procedures involved the beneficiation of the raw kaolin and calcinations at 850°C, to transform the kaolin to a more reactive metakaolin. Afterwards, the extremely reactive metakaolin was purge with sulphuric acid to obtain the much needed silica-alumina ratio for zeolite X synthesis. An alkaline fusion stage was then carried out to transform the metakaolin into zeolite by mixing with aqueous NaOH to form gel then allowed to stay for a duration of seven days at room temperature. The samples were then charged into a propylene container and placed in an oven at a temperature of 100°C for the reaction to take place for 6 h. Identification of the crystalline phases by X-ray Diffraction (XRD), chemical/elemental compositions by X-ray Fluorescence (XRF)/Energy Dispersive Spectroscopic analyses (EDS), surface morphology by Scanning Electron Microscopy (SEM) and molecular vibration of units by Fourier Transform Infrared Spectrophotometry (FT-IR) were done. The results showed that the zeolite synthesized from Chokocho kaolin (CK) was more crystalline/larger with sharper peaks on both XRD and FTIR than that from Kono-Boue. This was also supported by slightly rougher surface morphology of CK over KK on SEM. XRF Si:Al ratios of 10.73 and 14.36 were obtained for KK and CK respectively. EDS results supported the XRF ratios. Sharper zeolitic characteristic O-H stretching bands at 3488 and 3755 cm-1 were recorded for CK than KK. However, both results showed that zeolite X have been produced from both Kono-Boue and Chokocho kaolin clays respectively.
{"title":"Synthesis of Zeolite X from Locally Sourced Kaolin Clay from Kono-Boue and Chokocho, Rivers State, Nigeria","authors":"Victor Peter Maciver, K. Dagde, J. Konne","doi":"10.4236/aces.2020.104025","DOIUrl":"https://doi.org/10.4236/aces.2020.104025","url":null,"abstract":"This work describes the development of a process to produce zeolite X from mined kaolin clay from Kono-Boue and Chokocho, Rivers State, Nigeria. The procedures involved the beneficiation of the raw kaolin and calcinations at 850°C, to transform the kaolin to a more reactive metakaolin. Afterwards, the extremely reactive metakaolin was purge with sulphuric acid to obtain the much needed silica-alumina ratio for zeolite X synthesis. An alkaline fusion stage was then carried out to transform the metakaolin into zeolite by mixing with aqueous NaOH to form gel then allowed to stay for a duration of seven days at room temperature. The samples were then charged into a propylene container and placed in an oven at a temperature of 100°C for the reaction to take place for 6 h. Identification of the crystalline phases by X-ray Diffraction (XRD), chemical/elemental compositions by X-ray Fluorescence (XRF)/Energy Dispersive Spectroscopic analyses (EDS), surface morphology by Scanning Electron Microscopy (SEM) and molecular vibration of units by Fourier Transform Infrared Spectrophotometry (FT-IR) were done. The results showed that the zeolite synthesized from Chokocho kaolin (CK) was more crystalline/larger with sharper peaks on both XRD and FTIR than that from Kono-Boue. This was also supported by slightly rougher surface morphology of CK over KK on SEM. XRF Si:Al ratios of 10.73 and 14.36 were obtained for KK and CK respectively. EDS results supported the XRF ratios. Sharper zeolitic characteristic O-H stretching bands at 3488 and 3755 cm-1 were recorded for CK than KK. However, both results showed that zeolite X have been produced from both Kono-Boue and Chokocho kaolin clays respectively.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"104 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84624633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104024
R. Westphal, J. L. Pina, J. P. Franco, J. Ribeiro, Maicon Delarmelina, R. Fiorot, J. Carneiro, S. Greco
Three molecules containing morpholine, 1,4-naphthoquinone, 7-chloroquinoline and 1,3,5-triazine cores, scaffolds with recognized anti-corrosive activity, were synthesized and had their anticorrosive activity evaluated through potentiodynamic polarization and electrochemical impedance studies. Both studies were conducted in a simulated production water medium containing 150,000 mg·L-1 Cl- and 5 mg·L-1 S2-. Corrosion inhibition efficiency ranged from 67% - 86%, amongst which the naphthoquinone-containing derivative (compound 1) was the most effective. These compounds act through formation of a protective film on the surface of AISI 316 stainless steel. Investigation of the molecular properties of the prepared inhibitors by DFT calculations revealed that the LUMO energy and chemical hardness of the molecules can be directly correlated with their inhibition efficiency.
{"title":"Synthesis and Evaluation of Corrosion Inhibiting Activity of New Molecular Hybrids Containing the Morpholine, 1,4-Naphthoquinone, 7-Chloroquinoline and 1,3,5-Triazine Cores","authors":"R. Westphal, J. L. Pina, J. P. Franco, J. Ribeiro, Maicon Delarmelina, R. Fiorot, J. Carneiro, S. Greco","doi":"10.4236/aces.2020.104024","DOIUrl":"https://doi.org/10.4236/aces.2020.104024","url":null,"abstract":"Three molecules containing \u0000morpholine, 1,4-naphthoquinone, 7-chloroquinoline and 1,3,5-triazine cores, scaffolds \u0000with recognized anti-corrosive activity, were synthesized and had their \u0000anticorrosive activity evaluated through potentiodynamic polarization and \u0000electrochemical impedance studies. Both studies were conducted in a simulated production water medium containing 150,000 mg·L-1 Cl- and 5 mg·L-1 S2-. Corrosion \u0000inhibition efficiency ranged from 67% - 86%, amongst which the naphthoquinone-containing derivative (compound 1) \u0000was the most effective. These compounds act through formation of a protective \u0000film on the surface of AISI 316 stainless steel. Investigation of the molecular \u0000properties of the prepared inhibitors by DFT calculations revealed that the \u0000LUMO energy and chemical hardness of the molecules can be directly correlated \u0000with their inhibition efficiency.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"393 1","pages":"378-398"},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76913776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-02DOI: 10.4236/aces.2020.104020
A. Blessing, K. Dagde, J. G. Akpa
The simulation of a process plant for the production of propylene has been considered in this work. The reactor used for this research was a Continuous Stirred Tank Reactor (CSTR) which was deliberately picked because of the advantage of good temperature and reaction control. Other equipment includes a compressor, conversion reactor, cooler and splitter. Sizing was done for all equipment but detailed design was carried out for the CSTR since it’s the heart of the process plant. The principle of conservation of mass was applied for the development of basic design performance equations for the volume, the height, space time, space velocity and heat generated per unit volume at 90% conversion of propane to propylene. Aspen Hysys which is known for its reliability in chemical engineering process design was used to simulate the process plant and was used for all calculations and sizing of process equipment. The values of the functional and dimensional parameters which are required for the sizing of the reactor were obtained after the simulation with the following results: volume of reactor 37 m3, height of reactor 7.4 m, space time 0.028 hr, space velocity 59 hr-1 and heat load 78 kj/m3.
{"title":"Simulation of a Process Plant for the Production of Propylene","authors":"A. Blessing, K. Dagde, J. G. Akpa","doi":"10.4236/aces.2020.104020","DOIUrl":"https://doi.org/10.4236/aces.2020.104020","url":null,"abstract":"The simulation of a process plant for the production of propylene has been considered in this work. The reactor used for this research was a Continuous Stirred Tank Reactor (CSTR) which was deliberately picked because of the advantage of good temperature and reaction control. Other equipment includes a compressor, conversion reactor, cooler and splitter. Sizing was done for all equipment but detailed design was carried out for the CSTR since it’s the heart of the process plant. The principle of conservation of mass was applied for the development of basic design performance equations for the volume, the height, space time, space velocity and heat generated per unit volume at 90% conversion of propane to propylene. Aspen Hysys which is known for its reliability in chemical engineering process design was used to simulate the process plant and was used for all calculations and sizing of process equipment. The values of the functional and dimensional parameters which are required for the sizing of the reactor were obtained after the simulation with the following results: volume of reactor 37 m3, height of reactor 7.4 m, space time 0.028 hr, space velocity 59 hr-1 and heat load 78 kj/m3.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"17 1","pages":"322-331"},"PeriodicalIF":0.0,"publicationDate":"2020-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75269607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-13DOI: 10.4236/aces.2020.103016
Tombomieye Adokiye, Akpa Jackson Gunorubon, Dagde Kenneth Kenkugile
Dynamic Models for predicting the concentration profiles of the reactants and product in a Continuous Stirred Tank Reactor for the transesterification of used cooking oil (triglyceride) to biodiesel has been developed using the principle of conservation of mass. The developed system of differential equations were integrated numerically using fourth order Runge-Kutta algorithm embedded in ode 45 solver of 7.5 Mathlab program. The models were validated by solving the model equations with kinetic data and other relevant data from literatures. The results and trends were similar and in agreement with those from these literatures. Simulations of the reactor to (±) step changes in the inlet flowrates of the reactants (used cooking oil and methanol) showed great effect on biodiesel production, (instability—oscillations and reduction in output concentration of biodiesel). A feedback control strategy was developed with a Proportional-Integral (PI) Controller and a close loop model was developed for control studies. The closed loop response of the reactor output (biodiesel concentration) showed continuous oscillatory response with offset. Hence the controller parameters (proportional gain Kc and integral time ) were tuned using the “On-Line Trial and Error Method” implemented using MathLab Simulink to obtain optimum values that ensured quick stability of the closed-loop system, reduced or no oscillatory response and no offset. The optimum controller parameters were: proportional gain Kc ＝8.306 and integral time = 17.157 minutes.
{"title":"Modeling and Control of a Biodiesel Transesterification Reactor","authors":"Tombomieye Adokiye, Akpa Jackson Gunorubon, Dagde Kenneth Kenkugile","doi":"10.4236/aces.2020.103016","DOIUrl":"https://doi.org/10.4236/aces.2020.103016","url":null,"abstract":"Dynamic Models for predicting the concentration profiles of the reactants and product in a Continuous Stirred Tank Reactor for the transesterification of used cooking oil (triglyceride) to biodiesel has been developed using the principle of conservation of mass. The developed system of differential equations were integrated numerically using fourth order Runge-Kutta algorithm embedded in ode 45 solver of 7.5 Mathlab program. The models were validated by solving the model equations with kinetic data and other relevant data from literatures. The results and trends were similar and in agreement with those from these literatures. Simulations of the reactor to (±) step changes in the inlet flowrates of the reactants (used cooking oil and methanol) showed great effect on biodiesel production, (instability—oscillations and reduction in output concentration of biodiesel). A feedback control strategy was developed with a Proportional-Integral (PI) Controller and a close loop model was developed for control studies. The closed loop response of the reactor output (biodiesel concentration) showed continuous oscillatory response with offset. Hence the controller parameters (proportional gain Kc and integral time ) were tuned using the “On-Line Trial and Error Method” implemented using MathLab Simulink to obtain optimum values that ensured quick stability of the closed-loop system, reduced or no oscillatory response and no offset. The optimum controller parameters were: proportional gain Kc ＝8.306 and integral time = 17.157 minutes.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79194459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-13DOI: 10.4236/aces.2020.103009
Zina Jaja, J. G. Akpa, K. Dagde
An HYSYS model for the crude distillation unit of the Port Harcourt Refining Company has been developed. The HYSYS model developed includes 3 mixers, 3 heaters, 1 heat exchanger, 1 desalter (3-phase separator), 2-phase separator and the main fractionating column. The raw crude was characterized using Aspen HYSYS version 8.8 and the developed model was simulated with the industrial plant data from the Port Harcourt Refining Company. The HYSYS model gave component mole fractions of 0.2677, 0.1572, 0.2687, 0.0547, 0.2517 for Naphtha, Kerosene, Light Diesel Oil (LDO), Heavy Diesel Oil (HDO) and Atmospheric Residue and when compared to plant mole fractions of 0.2710, 0.1560, 0.2650, 0.0530, 0.2550 gave a maximum deviation of 3.2%. The HYSYS model was also able to predict the temperature and the tray of withdrawal for Naphtha, Kerosene, Light Diesel Oil (LDO), Heavy Diesel Oil (HDO) and Atmospheric Residue as follows: tray 1 (120°C), tray 12 (206°C), tray 25 (215°C), tray 35 (310°C) and tray 48 (320°C) which was also compared with plant data and gave a maximum deviation 23.2%. The HYSYS model was then optimized using Sequential Quadratic Programming (SQP) with the industrial plant data as starting values of operating conditions. The optimization increased the mass flow rate of Naphtha product from 7.512E+004 kg/hr to 7.656E+004 kg/hr, Kerosene product from 5.183E+004 kg/hr to 5.239E+004 kg/hr, Light Diesel Oil (LDO) product from 1.105E+005 kg/hr to 1.112E+005 kg/hr, Heavy Diesel Oil (HDO) from 2.969E+004 kg/hr to 2.977E+004 kg/hr while the last product being Atm Residue remained at 3.157E+005 kg/hr. The new optimum mole fraction values for the five products were as follows: 0.2713, 0.1540, 0.2635, 0.0528, and 0.2584 while corresponding optimum temperature values were as follows: 129°C, 221°C, 257°C, 317°C and 327°C.
建立了哈考特港炼油公司原油蒸馏装置的HYSYS模型。开发的HYSYS模型包括3台混合器、3台加热器、1台换热器、1台脱盐器(3相分离器)、2相分离器和主分馏塔。使用Aspen HYSYS 8.8版本对原油进行表征，并使用哈科特港炼油公司的工业工厂数据对所开发的模型进行了模拟。HYSYS模型对石脑油、煤油、轻柴油(LDO)、重柴油(HDO)和常压渣油的组分摩尔分数分别为0.2677、0.1572、0.2687、0.0547、0.2517，与植物的组分摩尔分数分别为0.2710、0.1560、0.2650、0.0530、0.2550，最大偏差为3.2%。HYSYS模型还能够预测石脑油、煤油、轻柴油(LDO)、重柴油(HDO)和常压渣油的提取温度和塔盘如下:塔盘1(120°C)、塔盘12(206°C)、塔盘25(215°C)、塔盘35(310°C)和塔盘48(320°C)，并与工厂数据进行比较，最大偏差为23.2%。然后使用顺序二次规划(SQP)将工业工厂数据作为操作条件的起始值，对HYSYS模型进行优化。优化后，石脑油产品的质量流量由7.512E+004 kg/hr提高到7.656E+004 kg/hr，煤油产品由5.183E+004 kg/hr提高到5.233 e +004 kg/hr，轻柴油(LDO)产品由1.105E+005 kg/hr提高到1.112E+005 kg/hr，重柴油(HDO)产品由2.969E+004 kg/hr提高到2.977E+004 kg/hr，最后的Atm渣产品保持在3.155 e +005 kg/hr。五个产物的最佳摩尔分数分别为0.2713、0.1540、0.2635、0.0528和0.2584，对应的最佳温度分别为129℃、221℃、257℃、317℃和327℃。
{"title":"Optimization of Crude Distillation Unit Case Study of the Port Harcourt Refining Company","authors":"Zina Jaja, J. G. Akpa, K. Dagde","doi":"10.4236/aces.2020.103009","DOIUrl":"https://doi.org/10.4236/aces.2020.103009","url":null,"abstract":"An HYSYS model for the crude distillation unit of the Port Harcourt Refining Company has been developed. The HYSYS model developed includes 3 mixers, 3 heaters, 1 heat exchanger, 1 desalter (3-phase separator), 2-phase separator and the main fractionating column. The raw crude was characterized using Aspen HYSYS version 8.8 and the developed model was simulated with the industrial plant data from the Port Harcourt Refining Company. The HYSYS model gave component mole fractions of 0.2677, 0.1572, 0.2687, 0.0547, 0.2517 for Naphtha, Kerosene, Light Diesel Oil (LDO), Heavy Diesel Oil (HDO) and Atmospheric Residue and when compared to plant mole fractions of 0.2710, 0.1560, 0.2650, 0.0530, 0.2550 gave a maximum deviation of 3.2%. The HYSYS model was also able to predict the temperature and the tray of withdrawal for Naphtha, Kerosene, Light Diesel Oil (LDO), Heavy Diesel Oil (HDO) and Atmospheric Residue as follows: tray 1 (120°C), tray 12 (206°C), tray 25 (215°C), tray 35 (310°C) and tray 48 (320°C) which was also compared with plant data and gave a maximum deviation 23.2%. The HYSYS model was then optimized using Sequential Quadratic Programming (SQP) with the industrial plant data as starting values of operating conditions. The optimization increased the mass flow rate of Naphtha product from 7.512E+004 kg/hr to 7.656E+004 kg/hr, Kerosene product from 5.183E+004 kg/hr to 5.239E+004 kg/hr, Light Diesel Oil (LDO) product from 1.105E+005 kg/hr to 1.112E+005 kg/hr, Heavy Diesel Oil (HDO) from 2.969E+004 kg/hr to 2.977E+004 kg/hr while the last product being Atm Residue remained at 3.157E+005 kg/hr. The new optimum mole fraction values for the five products were as follows: 0.2713, 0.1540, 0.2635, 0.0528, and 0.2584 while corresponding optimum temperature values were as follows: 129°C, 221°C, 257°C, 317°C and 327°C.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77308000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-13DOI: 10.4236/aces.2020.103010
Hamdy Farag, A. A. El-Hendawy, M. Kishida
In this work, the possibility of enhanced activity during the hydrodesulfurization of dibenzothiophene over certain nano-MoS2 catalyst due to the presence of H2S was examined by focusing on the reaction kinetics. With H2S generated in situ, the overall reaction followed the autocatalytic rate law; while in the absence of H2S the kinetics indicated a pseudo-first-order reaction. H2S appears to modify the relative contributions of parallel hydrogenation and desulfurization reactions by drastically increasing the hydrogenation rate. Kinetic models were developed that describe the hydrodesulfurization reaction at various H2S concentrations, and the kinetic parameters and adsorption equilibrium constants associated with this process were estimated by fitting the experimental data. The results suggest that the promotion and/or inhibition of hydrodesulfurization by H2S likely result from the same overall reaction mechanism.
{"title":"Kinetic Modelling of the Influence of H2S on Dibenzothiophene Hydrodesulfurization in a Batch System over Nano-MoS2","authors":"Hamdy Farag, A. A. El-Hendawy, M. Kishida","doi":"10.4236/aces.2020.103010","DOIUrl":"https://doi.org/10.4236/aces.2020.103010","url":null,"abstract":"In this work, the possibility of enhanced \u0000activity during the hydrodesulfurization of dibenzothiophene over certain \u0000nano-MoS2 catalyst due to the presence of H2S was \u0000examined by focusing on the reaction kinetics. With H2S \u0000generated in situ, the overall reaction followed the autocatalytic \u0000rate law; while in the absence of H2S the kinetics \u0000indicated a pseudo-first-order reaction. H2S appears to \u0000modify the relative contributions of parallel hydrogenation and desulfurization \u0000reactions by drastically increasing the hydrogenation rate. Kinetic models were \u0000developed that describe the hydrodesulfurization reaction at various H2S \u0000concentrations, and the kinetic parameters and adsorption equilibrium constants \u0000associated with this process were estimated by fitting the experimental data. \u0000The results suggest that the promotion and/or inhibition of \u0000hydrodesulfurization by H2S likely result from the same \u0000overall reaction mechanism.","PeriodicalId":7332,"journal":{"name":"Advances in Chemical Engineering and Science","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84158617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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