Pub Date : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I4.19362
H. Moussaoui, A. Idlimam, Abdelakder Lamharrar, M. Kouhila, Younes Bahammou, M. Mouhib, A. Amamou
Durum Wheat is deemed as one of the most important agricultural elements in the food system. Gamma irradiation treatment proves to be an efficient technique to decontaminate cereals so that we can ensure their hygienic quality during conservation. This paper seeks to study the hygroscopic behavior of irradiated and non-irradiated durum wheat at three temperatures 30 °C, 40 °C and 50 °C using the static gravimetric method. Furthermore, modeling the relationship between water activity and the equilibrium moisture content has been conducted through several models. GAB and Halsey were selected as convenient models that represent moisture sorption isotherms data for durum wheat. The net isosteric heat of sorption, the specific surface area of sorption was calculated via several equations including the Marquardt–Levenberg algorithm. As a result, the study of the samples reveals that the ionization at a low dose affects the moisture sorption of durum wheat
{"title":"The determination of moisture sorption isotherms and the isosteric heat of sorption for irradiated and non-irradiated durum wheat","authors":"H. Moussaoui, A. Idlimam, Abdelakder Lamharrar, M. Kouhila, Younes Bahammou, M. Mouhib, A. Amamou","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I4.19362","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I4.19362","url":null,"abstract":"Durum Wheat is deemed as one of the most important agricultural elements in the food system. Gamma irradiation treatment proves to be an efficient technique to decontaminate cereals so that we can ensure their hygienic quality during conservation. This paper seeks to study the hygroscopic behavior of irradiated and non-irradiated durum wheat at three temperatures 30 °C, 40 °C and 50 °C using the static gravimetric method. Furthermore, modeling the relationship between water activity and the equilibrium moisture content has been conducted through several models. GAB and Halsey were selected as convenient models that represent moisture sorption isotherms data for durum wheat. The net isosteric heat of sorption, the specific surface area of sorption was calculated via several equations including the Marquardt–Levenberg algorithm. As a result, the study of the samples reveals that the ionization at a low dose affects the moisture sorption of durum wheat","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49501566","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 : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I4.18680
A. Lahkimi, bouchra Louaste, I. Nechad, M. Chaouch, N. Eloutassi
Le present travail a ete entrepris dans le but de valoriser les plantes aromatiques et medicinales de la region de Dayet Aoua (Moyen Atlas, Maroc), plus particulierement de ces plantes. ajoute pour la pharmacopee marocaine en general; ce n'est autre que la lavande (Lavandula angustifolia). The chromatographic statistics with the Essential Components. Les monoterpenols sont representes par une domination du linalol (33,74% a 38,74%), suivis des monoterpenols. Les tests microbiologiques des huiles essentielles de Lavandula angustifolia ont un pouvoir antibacterien important vis-a-vis des bacteries a Gram positif. Il est egalement important de noter que la lavande a un effet inhibiteur sur la croissance du mycelium contre A. alternata, B. cinerea et F. oxysporum; la souche de B. cinerea semble etre la plus sensible a ce qu'il est compare aux autres souches representees par F. oxysporum et A. altern. Enfin, il convient egalement de noter que, selon les resultats obtenus, les huiles fixees de Lavandula presentent une activite anti-radicalaire par l'inhibition du DPPH, cette activite augmentant en fonction de la concentration. Compte tenu de toutes les donnees importantes qui demontrent les caracteristiques et l’importance de cette plante, confirmees et soutenues par cette etude, il semble necessaire d’intervenir dans toutes les interventions et jaloux des fonctionnaires et des chercheurs ainsi que des citoyens afin de maintenir cette plante afin de preserver soutenir ce type de plantes d'une part et de, d'autre part, la conservation de la biodiversite au Maroc en general et dans cette region en particulier.
{"title":"Antibacterial, antifungal and antioxidant activity of lavandula angustifolia of the middle atlas central (Morocco)","authors":"A. Lahkimi, bouchra Louaste, I. Nechad, M. Chaouch, N. Eloutassi","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I4.18680","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I4.18680","url":null,"abstract":"Le present travail a ete entrepris dans le but de valoriser les plantes aromatiques et medicinales de la region de Dayet Aoua (Moyen Atlas, Maroc), plus particulierement de ces plantes. ajoute pour la pharmacopee marocaine en general; ce n'est autre que la lavande (Lavandula angustifolia). The chromatographic statistics with the Essential Components. Les monoterpenols sont representes par une domination du linalol (33,74% a 38,74%), suivis des monoterpenols. Les tests microbiologiques des huiles essentielles de Lavandula angustifolia ont un pouvoir antibacterien important vis-a-vis des bacteries a Gram positif. Il est egalement important de noter que la lavande a un effet inhibiteur sur la croissance du mycelium contre A. alternata, B. cinerea et F. oxysporum; la souche de B. cinerea semble etre la plus sensible a ce qu'il est compare aux autres souches representees par F. oxysporum et A. altern. Enfin, il convient egalement de noter que, selon les resultats obtenus, les huiles fixees de Lavandula presentent une activite anti-radicalaire par l'inhibition du DPPH, cette activite augmentant en fonction de la concentration. Compte tenu de toutes les donnees importantes qui demontrent les caracteristiques et l’importance de cette plante, confirmees et soutenues par cette etude, il semble necessaire d’intervenir dans toutes les interventions et jaloux des fonctionnaires et des chercheurs ainsi que des citoyens afin de maintenir cette plante afin de preserver soutenir ce type de plantes d'une part et de, d'autre part, la conservation de la biodiversite au Maroc en general et dans cette region en particulier.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42718711","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 : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.20151
A. Oussaid, M. Azzouzi, A. Mansour, M. Azouagh, M. Koudad, A. Oussaid
The interest in natural conservatives, antimicrobial and antioxidants have slightly increased due to their advantageous effects. In this work bioactive compounds were obtained from Rosmarinus officinalis L. At first, the extractions of the essential oils by hydrodistillation was performed. The obtained essential oils from rosemary were yielded of about 1.8%. The GC-MS revealed that the rosemary oil was dominated by 1,8-cineol (52.440 %), Camphor (11.241 %), and α-pinene (8.225%). The extraction of the dry powders using maceration and soxhlet with solvents of different polarity showed a significant yield for ethanol compared to that of hexane. In the same context, the phytochemical screening revealed the richness of the studied plant with secondary metabolites. The antioxidant activity was assessed in vitro using scavenging activity of the free radical DPPH. It revealed that the essential oil and all ethanolic extracts tested using ascorbic acid as a reference, exhibit anti-radical activities. The ethanolic extract of Rosemary leaves showed the highest anti-radical activity (IC50 = 64.27µg/ml), followed by the extract of the latter's stems with an IC50 = 64.74µg/ml. The microbiological results showed that the antimicrobial activity was variable from one bacteria to another, this is due to the variability of the chemical composition of each extract.
{"title":"Assessment of the Chemical/biological activities of extracts and essential oil of Rosmarinus officinalis L. from the Oriental region of Morocco","authors":"A. Oussaid, M. Azzouzi, A. Mansour, M. Azouagh, M. Koudad, A. Oussaid","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.20151","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.20151","url":null,"abstract":"The interest in natural conservatives, antimicrobial and antioxidants have slightly increased due to their advantageous effects. In this work bioactive compounds were obtained from Rosmarinus officinalis L. At first, the extractions of the essential oils by hydrodistillation was performed. The obtained essential oils from rosemary were yielded of about 1.8%. The GC-MS revealed that the rosemary oil was dominated by 1,8-cineol (52.440 %), Camphor (11.241 %), and α-pinene (8.225%). The extraction of the dry powders using maceration and soxhlet with solvents of different polarity showed a significant yield for ethanol compared to that of hexane. In the same context, the phytochemical screening revealed the richness of the studied plant with secondary metabolites. The antioxidant activity was assessed in vitro using scavenging activity of the free radical DPPH. It revealed that the essential oil and all ethanolic extracts tested using ascorbic acid as a reference, exhibit anti-radical activities. The ethanolic extract of Rosemary leaves showed the highest anti-radical activity (IC50 = 64.27µg/ml), followed by the extract of the latter's stems with an IC50 = 64.74µg/ml. The microbiological results showed that the antimicrobial activity was variable from one bacteria to another, this is due to the variability of the chemical composition of each extract.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43100808","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 : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I4.20652
V. Nenov, G. Peeva, H. Yemendzhiev, M. Stancheva, F. Zerrouq
Wastewater and waste sludge are generated in all parts of the world during domestic and industrial activities. Conventional wastewater treatment methods generate a highly concentrated municipal sludge, which needs to be disposed of effectively without leading to secondary pollution. Animal manure and post generated manure wastewater are another environmental concern. Both of the above wastewater and sludge/manure are rich in organic/inorganic forms of carbon, nitrogen (N) and phosphorus (P). Anthropogenic and industrial activities in the global biogeochemical cycles have resulted in a drastic one-way mobilization of these resources into the atmosphere and the environment. The current intensive agriculture requires huge quantities of nitrogen (N) and Phosphorus (P) containing fertilizers. The industrial production of ammonia and nitrates is quite energy demanding; however, nitrogen is abundantly present in the nature and therefore it is a non-restricted resource for nitrogen derivate production. Unlike nitrogen, P can be obtained primarily from mineral deposits available only in few geographic locations. The phosphate rock reserves are finite and the current intensive fertilizer production based on economically mined rocks could last only another 50-100 years. Since phosphates are available only in limited geographic locations and the recognition that geologic phosphates are a non-renewable resource, Phosphorus recovery becomes a crucial for sustainable food production as EU depends for 90% on import of phosphate rocks (European Commission 2017). Within the EU only Finland has some phosphate rocks. The list of supplying countries is quite short; more than 70% of the present known global reserves of phosphate rock are located in Morocco as of all mined and processed phosphate rock (2009). Phosphorus, being a finite resource with deficits starting approximately from the year 2070 due to increased demand might also result in high prices and reliance on single point sources, giving them monopoly over the market. The EU phosphorus flows show that the main losses of phosphorus in the food sector are through sewage sludge, other waste water and food waste. In general, phosphorus can be recycled, mainly from wastewater (e.g. sewage water), manure and organic waste (e.g. wasted food). Thus, wastewater can be considered as a renewable source of N and P. Instead of releasing the N and P rich wastewater into coastal and inland waters increasing eutrophication risk their utilization can be beneficial resulting in multiple benefits like nutrient recovery, water reclamation for reuse and maintenance of ecological balance in aquatic systems. Presently, the recovery and reuse of P is still far from being a main stream practice. Yet, the techniques already accepted and applied differ by the origin of the used matter (wastewater, sludge, ash) are mainly focused on the process of precipitation. One of these techniques is struvite precipitation, which can be implemen
{"title":"Phosphorus consumption. From linear to circular flow","authors":"V. Nenov, G. Peeva, H. Yemendzhiev, M. Stancheva, F. Zerrouq","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I4.20652","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I4.20652","url":null,"abstract":"Wastewater and waste sludge are generated in all parts of the world during domestic and industrial activities. Conventional wastewater treatment methods generate a highly concentrated municipal sludge, which needs to be disposed of effectively without leading to secondary pollution. Animal manure and post generated manure wastewater are another environmental concern. Both of the above wastewater and sludge/manure are rich in organic/inorganic forms of carbon, nitrogen (N) and phosphorus (P). Anthropogenic and industrial activities in the global biogeochemical cycles have resulted in a drastic one-way mobilization of these resources into the atmosphere and the environment. The current intensive agriculture requires huge quantities of nitrogen (N) and Phosphorus (P) containing fertilizers. The industrial production of ammonia and nitrates is quite energy demanding; however, nitrogen is abundantly present in the nature and therefore it is a non-restricted resource for nitrogen derivate production. Unlike nitrogen, P can be obtained primarily from mineral deposits available only in few geographic locations. The phosphate rock reserves are finite and the current intensive fertilizer production based on economically mined rocks could last only another 50-100 years. Since phosphates are available only in limited geographic locations and the recognition that geologic phosphates are a non-renewable resource, Phosphorus recovery becomes a crucial for sustainable food production as EU depends for 90% on import of phosphate rocks (European Commission 2017). Within the EU only Finland has some phosphate rocks. The list of supplying countries is quite short; more than 70% of the present known global reserves of phosphate rock are located in Morocco as of all mined and processed phosphate rock (2009). Phosphorus, being a finite resource with deficits starting approximately from the year 2070 due to increased demand might also result in high prices and reliance on single point sources, giving them monopoly over the market. The EU phosphorus flows show that the main losses of phosphorus in the food sector are through sewage sludge, other waste water and food waste. In general, phosphorus can be recycled, mainly from wastewater (e.g. sewage water), manure and organic waste (e.g. wasted food). Thus, wastewater can be considered as a renewable source of N and P. Instead of releasing the N and P rich wastewater into coastal and inland waters increasing eutrophication risk their utilization can be beneficial resulting in multiple benefits like nutrient recovery, water reclamation for reuse and maintenance of ecological balance in aquatic systems. Presently, the recovery and reuse of P is still far from being a main stream practice. Yet, the techniques already accepted and applied differ by the origin of the used matter (wastewater, sludge, ash) are mainly focused on the process of precipitation. One of these techniques is struvite precipitation, which can be implemen","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49180821","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 : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I4.20152
A. Oussaid, M. Azouagh, A. Mansour, M. Azzouzi, M. Koudad
In the present work, the phytochemical study and evaluation of the antioxidant activities of the crude extracts of various solvents with increasing polarity (ethanol> acetone> dichloromethane > ethyl acetate > hexane) on fine dried cladode powder was studied. Each microwave oven power (500, 350, 160 and 90 W), of an Opuntia ficus-indica (OFI) medicinal species of the Cactaceae family collected in the rural commune of Bni Rais in Taourirt province of Oriental of Morroco. The phytochemical screening showed the presence of the studied chemical compounds (Flavonoids, Tannins, Quinones and Steroids) rich in powers of 500W and 350 W, especially in extracts with ethanol and acetone. The antioxidant activity of OFI cladodes extracts was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging method. The results obtained show that the acetone extracts have a very important activity, especially at the power of 500 W, IC50 = 0.29 mg/ml is found followed by the ethanol extract with a value of IC50 equal to 0.34 mg/ml. After the results we realize that the power 500 W showing antioxidant activity of each solvent extract (Et, Ac, Dc, AE and Hx) greater than that of the power 350, 160 and 90 W respectively (IC50: 500 W <350W <160 W <90 W). Also, the effect of microwaves on the duration of drying of the plant was assessed (40 min under microwave activation compared to 17.5h of conventional heating). The cleaning activities of all extracts, however, were significantly low compared to the reference standard of ascorbic acid with a sequence IC50 = 0.114 mg/ml, used at the same dose.
{"title":"Phytochemical study and evaluation of the antioxidant activity of extracts of Opuntia Ficus-Indica cladodes from the Oriental of Morocco and the effect of microwave activation on the drying time of the plant","authors":"A. Oussaid, M. Azouagh, A. Mansour, M. Azzouzi, M. Koudad","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I4.20152","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I4.20152","url":null,"abstract":"In the present work, the phytochemical study and evaluation of the antioxidant activities of the crude extracts of various solvents with increasing polarity (ethanol> acetone> dichloromethane > ethyl acetate > hexane) on fine dried cladode powder was studied. Each microwave oven power (500, 350, 160 and 90 W), of an Opuntia ficus-indica (OFI) medicinal species of the Cactaceae family collected in the rural commune of Bni Rais in Taourirt province of Oriental of Morroco. The phytochemical screening showed the presence of the studied chemical compounds (Flavonoids, Tannins, Quinones and Steroids) rich in powers of 500W and 350 W, especially in extracts with ethanol and acetone. The antioxidant activity of OFI cladodes extracts was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging method. The results obtained show that the acetone extracts have a very important activity, especially at the power of 500 W, IC50 = 0.29 mg/ml is found followed by the ethanol extract with a value of IC50 equal to 0.34 mg/ml. After the results we realize that the power 500 W showing antioxidant activity of each solvent extract (Et, Ac, Dc, AE and Hx) greater than that of the power 350, 160 and 90 W respectively (IC50: 500 W <350W <160 W <90 W). Also, the effect of microwaves on the duration of drying of the plant was assessed (40 min under microwave activation compared to 17.5h of conventional heating). The cleaning activities of all extracts, however, were significantly low compared to the reference standard of ascorbic acid with a sequence IC50 = 0.114 mg/ml, used at the same dose.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48060200","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 : 2020-07-02DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.21636
A. Nandiyanto
The isotherm adsorption of carbon microparticles prepared from pumpkin (Cucurbita maxima) seeds were studied and modelled. Experiments were done by evaluating carbon microparticles with various sizes (from 100 to 1000 um) for adsorbing curcumin (as a model of adsorbate) in an aqueous solution, and the results were derived and compared using the kinetics approach based on several standard isotherm adsorption models. Seven isotherm models were used to predict and determine the characteristic parameters: Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Flory-Huggins, Fowler–Guggenheim, and Hill-de Boer isotherm models. The results were then analyzed and accompanied by an adequate explanation related with the adsorption mechanisms and the determination techniques of its adsorption constants. The models showed that the interaction of adsorbates with carbon surface is done in multilayers with physical processes. Inorganic contents in the pumpkin seeds allow the formation of carbon with porosities, making more sites for the adsorption. The adsorbed molecules attract and associate with other free molecules. The adsorption is carried out on energetically different sites under an endothermic process. The Gibbs free energy confirmed that the adsorption is spontaneous. The results also confirmed that smaller adsorbent have direct impacts on the improving adsorption capacity (due to the existence of large surface area). Small-sized adsorbent (sizes < 500 um) has better additional adsorption (due to adsorbate-adsorbate interaction and possible existence of chemical interaction), resulting in the boosting adsorption capacity. This study is useful for further developments of carbon microparticles from organic waste material.
对南瓜籽制备的碳微粒的等温线吸附进行了研究和建模。通过评估不同尺寸（从100到1000μm）的碳微粒在水溶液中吸附姜黄素（作为吸附质的模型）来进行实验，并使用基于几种标准等温线吸附模型的动力学方法推导和比较结果。使用七个等温线模型来预测和确定特征参数：Langmuir、Freundlich、Temkin、Dubinin-Radushkevich、Flory Huggins、Fowler–Guggenheim和Hill de Boer等温线模型。然后对结果进行了分析，并对吸附机理及其吸附常数的测定技术进行了充分的解释。模型表明，吸附质与碳表面的相互作用是在具有物理过程的多层膜中进行的。南瓜籽中的无机成分允许形成具有孔隙的碳，从而形成更多的吸附位点。被吸附的分子吸引并与其他自由分子结合。吸附是在吸热过程中在能量不同的位点上进行的。吉布斯自由能证实吸附是自发的。结果还证实，较小的吸附剂对提高吸附能力有直接影响（由于存在较大的表面积）。小型吸附剂（尺寸<500um）具有更好的附加吸附（由于吸附质-吸附质相互作用和可能存在的化学相互作用），从而提高了吸附能力。这项研究有助于从有机废料中进一步开发碳微粒。
{"title":"Isotherm Adsorption of Carbon Microparticles Prepared from Pumpkin (Cucurbita maxima) Seeds Using Two-Parameter Monolayer Adsorption Models and Equations","authors":"A. Nandiyanto","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.21636","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.21636","url":null,"abstract":"The isotherm adsorption of carbon microparticles prepared from pumpkin (Cucurbita maxima) seeds were studied and modelled. Experiments were done by evaluating carbon microparticles with various sizes (from 100 to 1000 um) for adsorbing curcumin (as a model of adsorbate) in an aqueous solution, and the results were derived and compared using the kinetics approach based on several standard isotherm adsorption models. Seven isotherm models were used to predict and determine the characteristic parameters: Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Flory-Huggins, Fowler–Guggenheim, and Hill-de Boer isotherm models. The results were then analyzed and accompanied by an adequate explanation related with the adsorption mechanisms and the determination techniques of its adsorption constants. The models showed that the interaction of adsorbates with carbon surface is done in multilayers with physical processes. Inorganic contents in the pumpkin seeds allow the formation of carbon with porosities, making more sites for the adsorption. The adsorbed molecules attract and associate with other free molecules. The adsorption is carried out on energetically different sites under an endothermic process. The Gibbs free energy confirmed that the adsorption is spontaneous. The results also confirmed that smaller adsorbent have direct impacts on the improving adsorption capacity (due to the existence of large surface area). Small-sized adsorbent (sizes < 500 um) has better additional adsorption (due to adsorbate-adsorbate interaction and possible existence of chemical interaction), resulting in the boosting adsorption capacity. This study is useful for further developments of carbon microparticles from organic waste material.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46346967","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 : 2020-06-25DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.21063
I. Bazzi, M. Belkhaouda, A. A. Addi, A. Jmiai, L. Bammou, M. Hilali, R. Salghi
In this work, we investigate the corrosion behavior of steel rebar (SR) in four simulated concrete pore solutions (CPS): NaOH+KOH (CPS1), Na 2 CO 3 (CPS2), NaOH (CPS3) and Ca(OH) 2 (CPS4) medium. Effect of addition of Cl - anions as pollutant on pitting and uniform corrosion of SR is investigated by using potentiodynamic polarization (PDP) technic. The result obtained show that uniform and pitting corrosion of SR are strongly influenced by the nature of simulated CPS. In unpolluted CPS’s, only uniform corrosion of SR is observed in all cases. SR has excellent corrosion resistance in CPS4 compared to the other simulated CPS. In the polluted CPS’s by Cl - anions, we observe an accelerated uniform corrosion especially in CPS1, CPS3 and CPS4 mediums. The sensitivity to localized corrosion of SR varies from one simulated environment to another. It has the best resistance to pitting corrosion in polluted CPS3 medium. In CPS1 (pH = 13) and CPS2 (pH = 11.6) polluted by 3% NaCl, the tendency to pitting corrosion is the same. The localized attack is more pronounced in polluted CPS4 (pH=12.7). These results demonstrate that there are no limit values of the pH and the content of Cl - ions for the initiation of pitting and / or uniform corrosion. Therefore, it is the chemical composition of the simulated medium which imposes the pH value and the Cl - content for systematic corrosion study of the SR in the simulated CPS.
{"title":"Corrosion behaviour of steel rebar: effect of simulated concrete pore solution and chloride ions","authors":"I. Bazzi, M. Belkhaouda, A. A. Addi, A. Jmiai, L. Bammou, M. Hilali, R. Salghi","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.21063","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.21063","url":null,"abstract":"In this work, we investigate the corrosion behavior of steel rebar (SR) in four simulated concrete pore solutions (CPS): NaOH+KOH (CPS1), Na 2 CO 3 (CPS2), NaOH (CPS3) and Ca(OH) 2 (CPS4) medium. Effect of addition of Cl - anions as pollutant on pitting and uniform corrosion of SR is investigated by using potentiodynamic polarization (PDP) technic. The result obtained show that uniform and pitting corrosion of SR are strongly influenced by the nature of simulated CPS. In unpolluted CPS’s, only uniform corrosion of SR is observed in all cases. SR has excellent corrosion resistance in CPS4 compared to the other simulated CPS. In the polluted CPS’s by Cl - anions, we observe an accelerated uniform corrosion especially in CPS1, CPS3 and CPS4 mediums. The sensitivity to localized corrosion of SR varies from one simulated environment to another. It has the best resistance to pitting corrosion in polluted CPS3 medium. In CPS1 (pH = 13) and CPS2 (pH = 11.6) polluted by 3% NaCl, the tendency to pitting corrosion is the same. The localized attack is more pronounced in polluted CPS4 (pH=12.7). These results demonstrate that there are no limit values of the pH and the content of Cl - ions for the initiation of pitting and / or uniform corrosion. Therefore, it is the chemical composition of the simulated medium which imposes the pH value and the Cl - content for systematic corrosion study of the SR in the simulated CPS.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43019030","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 : 2020-06-16DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.19328
H. E. Alaoui-Belghiti, M. Bettach, I. Zdah, Y. Ennaciri, J. Assaoui, A. Zegzouti
With a view to finding solutions to the problems of Moroccan phosphogyosum (PG) in the long term, a research theme has been developed in our laboratory on the valorization of this residue by its conversion into marketable products by soft chemistry way less expensive. Thus, we investigated the optimal experimental conditions allowing a good efficiency of PG conversion by using NaOH to synthesize marketable products such as Ca(OH) 2 and Na 2 SO 4 of high purity. We varied the reagent concentrations and the attack durations to optimize these conditions. The quality of the products obtained is checked by XRD, IR and ICP to determine the distribution of PG impurities between obtained products. The morphology and size distribution were also established by SEM and laser granulometry.
{"title":"Optimization of conditions to convert phosphogypsum into Ca(OH)2 and Na2SO4","authors":"H. E. Alaoui-Belghiti, M. Bettach, I. Zdah, Y. Ennaciri, J. Assaoui, A. Zegzouti","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.19328","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.19328","url":null,"abstract":"With a view to finding solutions to the problems of Moroccan phosphogyosum (PG) in the long term, a research theme has been developed in our laboratory on the valorization of this residue by its conversion into marketable products by soft chemistry way less expensive. Thus, we investigated the optimal experimental conditions allowing a good efficiency of PG conversion by using NaOH to synthesize marketable products such as Ca(OH) 2 and Na 2 SO 4 of high purity. We varied the reagent concentrations and the attack durations to optimize these conditions. The quality of the products obtained is checked by XRD, IR and ICP to determine the distribution of PG impurities between obtained products. The morphology and size distribution were also established by SEM and laser granulometry.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46181378","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 : 2020-06-05DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.21127
N. Hassan, A. Shahat, A. El-didamony, M. El‐Desouky, A. El‐Bindary
Zeolitic imidazolate framework-8 (ZIF-8) is one type of (MOFs) that has been synthesized and characterized and detailed analysis of Crystal violet (CV) and Malachite Green (MG) adsorption behaviour. Impact of different variables on batch method as a function of solution pH, concentration of CV and MG, dose of ZIF-8, Contact time and temperature were analyzed and optimal test conditions were determined. Scanning electron microscopy (SEM) was used to measure surface alterations of the ZIF-8. The surface area and volume of the pores were found to be 495.199 m 2 g – 1 and 0.026 cm 3 g − 1 , respectively as determined by the Brunauer-Emmett-Teller (BET) test. ZIF-8 point of zero charging (pH PZC ) was calculated and was found 7.9. Adsorption data were modeled on isotherms for adsorption of Langmuir, Freundlich, Dubinin–Radushkevich and Temkin. Equilibrium data from the adsorption processes showed that the Langmuir is fitted with CV and MG adsorption. Pseudo-first order, pseudo-second order, kinetic models Weber and Morris and Elovich were used to analyze the kinetic data obtained at different initial dye concentrations. The kinetics of adsorption showed that the action in adsorption adopted the processes of pseudo-second - order kinetic model and chemisorption. The thermodynamic parameter such as ∆G, ∆S and ∆H has been determined. Study of thermodynamics for adsorption indicated the reaction was endothermal and spontaneous.
分子筛咪唑酸骨架-8 (ZIF-8)是目前合成的一种分子筛骨架，并对其晶体紫(CV)和孔雀石绿(MG)的吸附行为进行了详细的表征和分析。分析了溶液pH、CV和MG的浓度、ZIF-8的剂量、接触时间和温度等因素对分批法的影响，确定了最佳试验条件。采用扫描电镜(SEM)测量了ZIF-8的表面变化。通过bruauer - emmet - teller (BET)测试，发现孔隙的表面积和体积分别为495.199 m 2 g - 1和0.026 cm 3 g - 1。计算ZIF-8零充电点(pH PZC)，结果为7.9。采用等温线模拟了Langmuir、Freundlich、Dubinin-Radushkevich和Temkin的吸附数据。吸附过程的平衡数据表明，Langmuir符合CV和MG的吸附。采用Weber、Morris和Elovich等准一级、准二级动力学模型对不同初始染料浓度下的动力学数据进行了分析。吸附动力学表明，吸附过程采用准二级动力学模型和化学吸附过程。确定了∆G、∆S、∆H等热力学参数。吸附热力学研究表明，该反应为吸热自发反应。
{"title":"Equilibrium, Kinetic and Thermodynamic studies of adsorption of cationic dyes from aqueous solution using ZIF-8","authors":"N. Hassan, A. Shahat, A. El-didamony, M. El‐Desouky, A. El‐Bindary","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.21127","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.21127","url":null,"abstract":"Zeolitic imidazolate framework-8 (ZIF-8) is one type of (MOFs) that has been synthesized and characterized and detailed analysis of Crystal violet (CV) and Malachite Green (MG) adsorption behaviour. Impact of different variables on batch method as a function of solution pH, concentration of CV and MG, dose of ZIF-8, Contact time and temperature were analyzed and optimal test conditions were determined. Scanning electron microscopy (SEM) was used to measure surface alterations of the ZIF-8. The surface area and volume of the pores were found to be 495.199 m 2 g – 1 and 0.026 cm 3 g − 1 , respectively as determined by the Brunauer-Emmett-Teller (BET) test. ZIF-8 point of zero charging (pH PZC ) was calculated and was found 7.9. Adsorption data were modeled on isotherms for adsorption of Langmuir, Freundlich, Dubinin–Radushkevich and Temkin. Equilibrium data from the adsorption processes showed that the Langmuir is fitted with CV and MG adsorption. Pseudo-first order, pseudo-second order, kinetic models Weber and Morris and Elovich were used to analyze the kinetic data obtained at different initial dye concentrations. The kinetics of adsorption showed that the action in adsorption adopted the processes of pseudo-second - order kinetic model and chemisorption. The thermodynamic parameter such as ∆G, ∆S and ∆H has been determined. Study of thermodynamics for adsorption indicated the reaction was endothermal and spontaneous.","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43093727","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 : 2020-06-03DOI: 10.48317/IMIST.PRSM/MORJCHEM-V8I3.20510
E. Hadrami, F. E. Aroussi, I. Fichtali, A. Farah, A. Bentama
A series of novel 1,2,3-triazolic compounds derived from natural products (thymol, carvacrol and eugenol) was synthesized by the copper(I)-catalyzed alkyne-azide (CuAAC) cycloaddition between the corresponding propargyl ethers of each natural product and a variety of azides. The reaction conducted with catalytic amount of copper (II) sulfate and sodium ascorbate affording desired products in good yields and their structures were confirmed by spectral techniques such as 1 H NMR, 13 C NMR and high resolution mass spectrometry ( HRMS).
{"title":"Synthesis of novel 1,2,3-triazolic compounds derived from natural product, by the copper(I)-catalyzed alkyne-azide (CuAAC) cycloaddition","authors":"E. Hadrami, F. E. Aroussi, I. Fichtali, A. Farah, A. Bentama","doi":"10.48317/IMIST.PRSM/MORJCHEM-V8I3.20510","DOIUrl":"https://doi.org/10.48317/IMIST.PRSM/MORJCHEM-V8I3.20510","url":null,"abstract":"A series of novel 1,2,3-triazolic compounds derived from natural products (thymol, carvacrol and eugenol) was synthesized by the copper(I)-catalyzed alkyne-azide (CuAAC) cycloaddition between the corresponding propargyl ethers of each natural product and a variety of azides. The reaction conducted with catalytic amount of copper (II) sulfate and sodium ascorbate affording desired products in good yields and their structures were confirmed by spectral techniques such as 1 H NMR, 13 C NMR and high resolution mass spectrometry ( HRMS).","PeriodicalId":18768,"journal":{"name":"Moroccan Journal of Chemistry","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46329288","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：