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Characterization of the Natural and Organomodified Clay Soil of Moukosso (Republic of Congo) by Dimethylsulfoxide: Application to the Adsorption of Lead (II) in Aqueous Solution
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作者 Ottard Arnaud M. R. Ossiby Mwa Ngo Ferland Ngoro-Elenga +3 位作者 Erman E. Nzaba Madila Zita F. Diamouangana Mpissi Exaucé R. Kinzonzi Ngongot Joseph Marie Moutou 《Materials Sciences and Applications》 CAS 2023年第2期63-77,共15页
In this study, the authors characterized the raw clayey soil of Moukosso and modified by dimethylsulfoxide (DMSO) by several analytical methods, namely: X-ray diffraction (XRD), Fourier transform infrared (FTIR) and g... In this study, the authors characterized the raw clayey soil of Moukosso and modified by dimethylsulfoxide (DMSO) by several analytical methods, namely: X-ray diffraction (XRD), Fourier transform infrared (FTIR) and gravimetric thermal analysis (TGA). The cation exchange capacity (CEC) was also determined. Mineralogical analysis by XRD revealed the presence of muscovite (29.7%), kaolinite (8.9%), anatase (2.4%) and quartz (58.9%). The characterization of the organo-clay by infrared and by thermogravimetric analysis confirmed the intercalation of DMSO by the presence of vibration bands at 1008 cm<sup>-1</sup> and 1070 cm<sup>-1</sup> and a strong increase in the loss of mass. The cation exchange capacity of the raw material is 7.4 meq/100g. Rapid adsorption of Pb<sup>2+</sup> ions was observed between 5 and 15 minutes of stirring time in both cases (raw clay and organomodified clay). The modeling of the isotherms by the models of Langmuir and Freudlich showed that these are of type S with a maximum amount of adsorption of 22.471 mg/g for the fine fraction and 41.493 mg/g for the clay intercalated with DMSO. Langmuir’s model best reproduces the experimental data of this study. 展开更多
关键词 Clay DIMETHYLSULFOXIDE ORGANOCLAY CHARACTERIZATION ADSORPTION ISOTHERM Moukosso
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Effect of Cooking Condiments on the Mass Loss of Artisanal Aluminum Cooking Utensils: The Case of Congo—Brazzaville
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作者 Thierry Arcady Vila Noemie Grace Mazel Ifo +5 位作者 Jean-Claude Bibila Mafouba Vivien Igor Banzouzi Samba Mpissi Zita Flora Diamouangana Nursie Rarahu Oba Mboho Christ Dorvy Privillège Tsaty Nsimba Joseph-Marie Moutou 《Journal of Minerals and Materials Characterization and Engineering》 2022年第2期139-152,共14页
Corrosion of cookware is a growing concern for the durability of materials. A rapidly emerging theme that is one of the major current societal challenges at the interface of environmental and health issues. In this pr... Corrosion of cookware is a growing concern for the durability of materials. A rapidly emerging theme that is one of the major current societal challenges at the interface of environmental and health issues. In this present work, the corrosion of aluminum in food environments (salt water and fresh tomatoes) was studied. The three aluminum utensils were purchased in the various workshops in Brazzaville (Republic of the Congo). The weight loss method followed the effect of cooking media on cookware, X-ray diffraction (XRD) and fluorescence (XRF) are two methods used to characterize alloys. XRF analysis indicates that the samples consist of aluminum as a basic element. XRD reveals that the essential building blocks of cookware samples are aluminum, silicon, iron, copper, magnesium and zinc. Finally, gravimetric measurements are carried out to assess the mass losses of samples of artisanal kitchen utensils when cooking food. Aluminum is found to be sensitive in TF and OS media. 展开更多
关键词 Kitchen Utensils Corrosion Loss of Mass Intermetallic Compounds ALUMINUM Salt Water XRD
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Health Risk Assessment of Heavy Metals in the Water of the LoutétéRiver, Mfouati District, Southeast Congo
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作者 Ifo Grace Mazel Diamouangana Mpissi Zita Flora +1 位作者 Bibila Mafoumba Jean Claude Matini Laurent 《Journal of Geoscience and Environment Protection》 2022年第12期77-86,共10页
The overall objective of this study was to assess the health risk of water in the Loutété River contaminated with heavy metals. Six surface water samples were collected during the dry season (October 2014). ... The overall objective of this study was to assess the health risk of water in the Loutété River contaminated with heavy metals. Six surface water samples were collected during the dry season (October 2014). The physico-chemical parameters (pH, electrical conductivity, total dissolved salts) were measured using a HANNA brand device. The values of these physico-chemical parameters are below the WHO standards. The concentrations of heavy metals Cr, Cu, Fe, Pb, Zn and Mn were determined by ICP-OES. These obtained in (μg/L) are in the range: Cr (0.08 - 5.8);Cu (0.6 - 14.5);Fe (0.2 - 386.05);Pb (1.02 - 370.09);Zn (8.02 - 248.7) and Mn (37.1 - 328.08). These concentrations are below the WHO drinking water guideline value in all samples for Cr, Cu, Mn and Zn, 50, 2000, 400 and 3000 μg/L respectively. Concentrations of As, Fe and Pb exceeded the WHO guideline value for drinking water at the following stations: S1 for arsenic, S4 for iron, and for Pb at all stations except S5. The health risk assessment for adults due to ingestion exposure gave HQing. values < 1 for the following heavy metals: Cr, Cu, Fe, Mn, Zn, except for Arsenic and Lead. The hazard quotient calculated by dermal contact (HQ derm) in the waters of the river Loutété, showed that HQ derm < 1 for all heavy metals in all stations. For children, the dermal contact hazard quotient HQ derm < 1 for all heavy metals As, Fe, Cu, Zn, Mn, Cr and Pb. With the exception of station S4, we observed that HQ > 1 for lead. In the case of ingestion, HQing. < 1 for the heavy metals Cr, Cu, Zn, Mn, with the exception of the following metals Arsenic, Lead and Iron. 展开更多
关键词 Hazard Quotient Non-Carcinogenic Risk Heavy Metals
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Characterization and Valuation of a Clay Soil Sampled in Londéla-Kayes in the Republic of Congo 被引量:1
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作者 Roger Makosso Voula Flora Zita Mpissi Diamouangana +3 位作者 Joseph-Marie Moutou Vivien Igore Banzouzi Samba Mozalin Paul Foutou Julien Placide Ngoma 《Journal of Minerals and Materials Characterization and Engineering》 2021年第2期117-133,共17页
In order to characterize and enhance clay collected in Londéla-kayes in the Republic of Congo, in this work, it was a question of proceeding to the mineralogical, physico-chemical, thermal and geotechnical charac... In order to characterize and enhance clay collected in Londéla-kayes in the Republic of Congo, in this work, it was a question of proceeding to the mineralogical, physico-chemical, thermal and geotechnical characterization of this clay. Next, determine the technological properties of fired bricks. For this, various methods were used in particular: X-ray diffraction, infrared spectroscopy, gravimetric thermal analysis and differential thermal analysis, dilatometric analysis, scanning electron microscopy, specific surface and analysis chemical. It appears that, for the mineralogical characterization, kaolinite is the most abundant mineral of this clay. The results of dilatometric analysis have shown that this clay can be fired at low temperatures. The geotechnical characterization showed that it is plastic clay thus exhibiting a high shrinkage. The results of the technological properties of LON1 bricks have shown that this clay cannot be used in the manufacture of fired bricks. The geotechnical properties must be improved by adding additives in order to improve the technological properties of the fired bricks. 展开更多
关键词 CLAY CHARACTERIZATION VALUATION
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Study of the Curing Temperature of 600°C, 700°C and 800°C of Mouyondzi Clay on the Mechanical, Physical and Microstructural Properties of Geopolymer Obtained
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作者 Vezolo Stanislas Ifo Grace Mazel +3 位作者 Foutou Paul Mozalin Loubaki Raunel Diamouangana Zita Flora Moutou Joseph-Marie 《Journal of Minerals and Materials Characterization and Engineering》 2022年第2期185-197,共13页
This work consists of determining the right curing temperature for Mouyondzi clay, with a view to obtaining a very reactive metakaolinic amorphous phase, which will give us a geopolymer with good physical and mechanic... This work consists of determining the right curing temperature for Mouyondzi clay, with a view to obtaining a very reactive metakaolinic amorphous phase, which will give us a geopolymer with good physical and mechanical performance. The kaolin-dominant Mouyondzi clay was calcined at 600℃, 700℃ and 800℃ with a heating rate of one degree per minute. In order to achieve the objective of this work, the performance of geopolymer was measured by compressive strength on geopolymer prisms of 28 days of age, by XRD and IRFT of geopolymer powders, calcined clay and raw clay, and by SEM of geopolymer blocks. Analysis of the results shows that the resistance value increases with the curing temperature of the clay and reaches a maximum of 49 MPa at 800℃. At 600℃ we already have 31 MPa, the equivalent of Portland cement with the addition. The XRD confirms the disappearance of clay species from 600℃. At 800℃ there is not yet the appearance of a new crystalline phase. Quartz is the only mineral species present. We can therefore confirm that at 800℃, the geopolymer obtained exhibits higher physical and mechanical performance than the other curing temperatures studied for Mouyondzi clay. This is confirmed by the appearance of a new aluminosilicate phase in the IRFT spectra and in the SEM images appearing as a continuous plate. 展开更多
关键词 GEOPOLYMER Compressive Strength Mouyonszi Clay Amorphous Phase
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