Articles - CSN

Study of the adsorption of Nickel ions on Sodium alginate polymeric membrane in hydrometallurgical effluents

Publication Date : 31/03/2024

DOI: 10.59228/rcst.024.v3.i1.75


Author(s) :

Zuka Maniania B, Muntumosi Senzedi M. , Mbungu Tsumbu J. P, Mulaba Bafubiandi A, Bopili Mbotia Lepiba R, Eyumu L.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

Mining extraction activities in the Democratic Republic of Congo result in the production of hydrometallurgical effluents containing varying concentrations of metallic ions. These effluents are often discharged into the environment without proper treatment, leading to ecological imbalances and severe illnesses in animals and humans. It is crucial to treat these effluents before releasing them into the natural environment. This study presents a technical approach for developing polymeric membranes capable of adsorbing metallic ions from aqueous solutions of hydrometallurgical effluents. A sodium alginate polymeric membrane was synthesized and characterized using various techniques including X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, X-Ray Fluorescence, Transmission Electronic Microscopy, Differential Scanning Calorimetry, and Mechanical Traction. Adsorption experiments were conducted using aqueous solutions of nickel sulphate prepared in the laboratory and hydrometallurgical aqueous solutions from a factory. The results showed that the adsorption of nickel (Ni2+) ions on the polymeric membrane is faster in the hydrometallurgical solution compared to the nickel sulphate solution. This phenomenon appears to be mainly governed by short-range forces such as Van der Waals forces. The Hill-Langmuir model was used to describe the adsorption experiments, and the analysis of the model parameters indicated that the adsorption of Ni2+ ions on the sodium alginate polymeric membrane is more efficient in solutions containing only one type of ion compared to complex aqueous solutions. This is due to the competition between different metallic ions present in complex solutions, which are not the case in the nickel sulphate solution where only Ni2+ ions are present. Furthermore, the analysis showed that the coordination number (n) for Ni2+ ions in a "receiving" site of the polymeric membrane is smaller in the nickel sulphate solution (2.22) compared to the hydrometallurgical aqueous solution (2.85).


No. of Downloads :

4


Étude de l’adsorption des ions de Nickel sur des argiles naturelles locales dans les effluents hydrométallurgiques

Publication Date : 31/03/2024

DOI: 10.59228/rcst.024.v3.i1.74


Author(s) :

Zuka Maniania B, Muntumosi Senzedi M. , Mbungu Tsumbu J. P, Mulaba Bafubiandi A, Mbonsei Lobota A, Lofutu Bolemole G , Bopili Mbotia Lepiba R.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

This research focuses on the treatment of hydrometallurgical effluents, specifically studying the adsorption of metallic ions such as Nickel, Copper, Cobalt, Mercury, and lead on natural clays from the Democratic Republic of Congo (DRC). Twelve clay samples, six activated with a strong acid and six non-activated, were characterized using various techniques including X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, X-Ray Fluorescence, Transmission Electron Microscopy, and chemical dosage. The characterization revealed that the clays are mixed with several clayey minerals, enriched in aluminum silicate; contain absorption and water retention sites, and exhibit heterogeneities at the interfaces between grains and exchangeable ions. Activating the clays increased their cation exchange capacities, removed impurities, and increased pore size and specific area. Two aqueous solutions were used in the experiments: a laboratory-prepared nickel sulfate solution and a hydrometallurgical aqueous solution from a factory, both initially containing 15 mgL-1 of Ni2+ ions. Results showed that the adsorption of Ni2+ ions increased with the quantity of clay in the solution. The activated clays adsorbed more ions than non-activated clays at the same Ni2+ ion concentration. Additionally, adsorption was weaker in the hydrometallurgical solution compared to the nickel sulfate solution, suggesting competition from other metallic ions. The optimal adsorption occurred with chemically activated clays containing high Na+ , Fe2+ , and Al3+ ion content and low K+ ion content. The Hill-Langmuir model was used to describe the adsorption results, revealing that minimal quantities of activated clay were needed to adsorb a large quantity of Ni2+ ions in the solution, whereas large quantities of non-activated clays were insufficient. In conclusion, the research demonstrates the potential of natural clays from the DRC to adsorb metallic ions from hydrometallurgical effluents, providing insights for effective treatment methods in the future. The model revealed that the clay samples A2a clay, A6a and A3na have the very elevated reactional sites concentrations.


No. of Downloads :

10


Influence des essences forestières arborescentes sur la productivité des bananiers au deuxième cycle cultural à Kinshasa, RDC.

Publication Date : 27/03/2024

DOI: 10.59228/rcst.024.v3.i1.73


Author(s) :

Bangata Bitha Nyi Mbunzu Jean Christian, Mobambo Kitume Ngongo Patrick.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

Silvo-banana systems are an effective response, on the one hand, to the problems of improving banana productivity, and on the other, to the preservation of our forests, especially in regions where deforestation is increasing. In order to improve banana production in Kinshasa, an evaluative study of silvo-banana systems was carried out under Batéké plateau conditions. The aim was to compare different banana-tree associations, in order to determine their impact on banana productivity. Five banana cultivars were combined with twelve tree species, divided into three groups: legumes, non-legumes and fruit trees. The aim of this study was to evaluate the influence of forest trees on the behavior of banana plants during the second production cycle. These banana plants were derived from successor shoots selected at the end of the first production cycle. With regard to the results obtained with PCA, it should be noted that of the 60 forest-banana associations studied, the most successful (high bun weight and yield) were those formed with the cultivar Nsikumuna in association with: Pterocarpus indicus Willd; Millettia laurentii; Maesopsis eminii Engl; Gmelina arborea Roxb; Eugenia malaccensis L.; Lannea welwitschii (Hiern) Engl; Persea americana; Terminalia superba Anglais. & Diels; Mangifera indica L. and Dacryodes edulis. All these species can be selected and recommended for use in silvobanana systems, with particular emphasis on the first four.


No. of Downloads :

5


L’impact de la documentation dans une entreprise : Cas de l’OCC et de l’OGEFREM en République Démocratique du Congo

Publication Date : 27/03/2024

DOI: 10.59228/rcst.024.v3.i1.72


Author(s) :

Makengo Dingombe Michel, Lilomba Bokila Simon.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

Regardless of the type of company, it receives and produces documentation within the context of the information warfare that 21st-century enterprises are constantly engaged in. In this competitive context, it is vulnerable and requires information management professionals. At this time when the DRC is planning its emergence by 2030, documentalists, librarians, and archivists must be aware of the role they have to play in national development. However, it is also necessary for planners and decision-makers to be sufficiently sensitized so that the appropriate conditions are created without which documentation centers, libraries, and archives would not be able to make their maximum contribution and participate effectively in the activities of national and international networks. To achieve this, it is important to encourage children, future managers, and decision-makers, from a young age, to visit libraries, documentation centers, archives, and why not museums.


No. of Downloads :

3


Financement et indépendance de la Commission Electorale Nationale Indépendante aux élections de 2006 et 2011 en République Démocratique du Congo

Publication Date : 27/03/2024

DOI: 10.59228/rcst.024.v3.i1.71


Author(s) :

Yannick Liolocha Heradi.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

The question of legitimacy of the leaders in the Democratic Republic of Congo has been in the headlines for more than a decade. Thus, a democracy support institution, which is the CENI, was set up and consecrated by the constitution of February 18, 2006 to ensure the neutrality of the electoral process. This commission was perceived by the population as a real opportunity that could not only allow the country to emerge from its crisis, but also ensure the organization of free, transparent and democratic elections ; with a heavy responsibility for ensuring sound and transparent management of the funds allocated to electoral operations. It is thus demonstrated that external financing has compromised its independence, leading to parallel administration and contested elections. This finding raises questions about the impact of financing on its independence and the main areas of expenditure. Logistic challenges and internal and external financial controls are factors that have hindered its operations.


No. of Downloads :

12


Profil épidémio-clinique de la Drépanocytose et Prédiction des propriétés pharmacocinétiques et toxicologiques des médicaments utilisés dans la prise en charge au Centre de Médecine Mixte et d’Anémie SS (Kinshasa, R.D. Congo)

Publication Date : 27/03/2024

DOI: 10.59228/rcst.024.v3.i1.70


Author(s) :

Koto-Te-Nyiwa Jean-Paul Ngbolua, Colette Masengo Ashande, Steve Kodondi Dibere, Narcisse B. Basosila, Eliane K. Ikanga, Delly B. Mbembe, Jason T. Kilembe , Dorothée D. Tshilanda, Damien S.T. Tshibangu, Pius T. Mpiana.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

Sickle cell disease or SS anaemia is the most common haemoglobinopathy in the world and is a major public health problem in endemic regions. The aim of the present study was to conduct a survey in a specialised centre in order to evaluate the cost of care, to identify the infectious diseases associated with sickle cell disease and the drugs used to combat them and then to predict the pharmacokinetic and toxicological properties of these drugs and of the phyto-markers contained in Lippia multiflora, a plant used in the alternative management of this haemoglobinopathy. This study shows that the female sex is more numerous than the male sex (54.5% vs. 45.5%); the 6-15 year age group is predominant (81%); the major complications noted are sepsis (62%); broad-spectrum antibiotics are prescribed for 87.5% while antimalarials are prescribed for 47.0%; the cost of care for sickle cell disease patients is estimated at more than 100 USD (˃200. 000 CDF) for 52.5% of patients for each crisis; the management of sickle cell disease by traditional medicine combined with modern medicine, particularly the combination of plant extracts with antibiotics, represents a risk of drug interaction for patients. It is therefore desirable that further studies be conducted on the antibacterial activity of Lippia multiflora to verify whether this plant is not endowed with intrinsic activity against the bacteria associated with sickle cell disease.


No. of Downloads :

11


Evaluation des impacts environnementaux et des risques associés : Etude de cas sur le gisement de Fer de Bekisopa, Madagascar

Publication Date : 26/03/2024

DOI: 10.59228/rcst.024.v3.i1.69


Author(s) :

Robijaona Rahelivololoniaina B, Razakamanana T, Rakotonirina M. D. L, Razafindrazanakolona A. D, Ramanampisoa V. E, Pius T. Mpiana, Koto-Te-Nyiwa Ngbolua.


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

The study analyses the environmental impacts of mining the Bekisopa iron ore deposit, using a precise methodology. It identifies the direct impacts, focusing on the physical, atmospheric and aquatic spheres, in particular the risks associated with mine tailings and waste. In accordance with the MECIE decree (1997), the study highlights the consequences throughout the mining cycle. It anticipates and prevents risks, from the degradation of ecosystems to the alteration of water resources. Impacts and risks are classified by receiving environment, with an assessment of their quality. Recommendations are put forward for mitigating impacts and risks, focusing on minimising mining waste and its treatment, and engaging local stakeholders to raise awareness of the environmental issues involved in mining the Bekisopa iron ore deposit.


No. of Downloads :

12


Accès aux services de l’Hôpital Pédiatrique de Kalembe Lembe (Kinshasa, République Démocratique du Congo) par la population

Publication Date : 26/03/2024

DOI: 10.59228/rcst.024.v3.i1.68


Author(s) :

Nienie Bwabitulu Alexis, Kambondji Bukaya Jean Pierre , Kamanda wa Kamanda Jean Claude, Kazadi Tshiamala Evariste .


Volume/Issue :
Volume 3
,
Issue 1
(03 - 2024)



Abstract :

This study attempts to analyze access to the services of the Kalembelembe Pediatric Hospital in order to identify the factors that predispose access to the health services of this facility. The aim is to identify the factors influencing access to health care services offered by the Kalembelembe Pediatric Hospital to the population of Kinshasa, in order to help improve the role and place of this facility in the health care provision of the city of Kinshasa. We conducted a stratified random sample survey of factors predisposing to hospital access. The data were processed using a variety of techniques, including geographic information system (GIS) mapping and correlation analysis. Examination of the indices relating to patient attendance by commune revealed the geographical origins of recruitment, in particular the different health zones of the provincial city of Kinshasa. Our investigations revealed that financial resources, the proximity of the hospital to the home, and the quality of care provided by the competent nursing staff are all factors that predispose people to access healthcare at the Kalembelembe Pediatric Hospital. Poor access to paediatric healthcare is a major public health problem. To remedy this, it is up to the central government to implement paediatric medical training based on need rather than income, in order to reduce disparities in utilization, ensure fair access and achieve an equitable distribution of the cost constraints associated with medical health services.


No. of Downloads :

3