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Zimbabwe possesses abundant mineral resources, which could propel the country's economic growth if they are properly beneficiated to produce value- added products. However, the country has failed to leverage its mineral endowment to drive sustainable socioeconomic transformation. This study aimed to evaluate the viability of mineral beneficiation in Zimbabwe's mining sector by analysing the factors that affect its competitiveness and identifying strategic interventions to improve the industry's competitiveness. The study employed Michael Porter's Diamond Model of industry competitiveness to analyse the mining industry's competitiveness in Zimbabwe and to assess the model's applicability in the country's context. The study findings reveal that Zimbabwe's mining sector is not currently competitive and does not facilitate mineral beneficiation. Additionally, the study finds that the Porter Diamond Model is not entirely relevant to the Zimbabwean context because it is primarily applicable to developed nations. The study recommends strategic interventions that could transform Zimbabwe's comparative advantage in the mining sector into a competitive advantage. [ABSTRACT FROM AUTHOR]

The present paper discusses the dissolution of cobalt‐bearing minerals from a copper‐cobalt ore using probabilistic models where a priori and a posteriori knowledge of leaching are used to predict the dissolution of cobalt‐bearing minerals in a sulphuric acid medium in the presence of a reducing agent. Priorly, the dissolution of cobalt‐bearing minerals depends on their mineralogy, leading to the use of FeSO4 as a reducing agent for the trivalent (Co3+) form of cobalt (CoOOH). A posteriori, the dissolution of Co3+ is improved by the presence of ferrous ions, resulting from the dissolution of Fe‐bearing minerals, including Fe from Co(Fe)OOH. The results showed that the predictive‐oriented probabilistic graphic models based on the Bayesian approach, in combination with the design of the experiment data, made it possible to model the leaching of cobalt‐bearing minerals. The results from the design of the experiment using the experimental tree methodology associated with the optimization of the multiple responses in a multiple input for a multiple output set‐up derived the following optimized parameters: 60°C for the temperature (T), 850 rpm for the agitation, 40% for the solid percentage, 1.5 for the pH, and 4 g/L for the concentration of the Fe2+ ion. The cobalt dissolution yield obtained was 89.95%. The analysis of the dependence between the random variables only (P(Fe2+|T), P(pH|T), and P(Fe2+|pH)) and the dependence between the random variables and the responses (P(Co‐yield|pH, Eh)) allowed the construction of two Bayesian networks, respectively, with and without posterior knowledge. For the Bayesian network with posteriori knowledge, the {5–2} structure was found to be the most appropriate arrangement. The model predicted a cobalt yield value, and the experimental value indicated a correlation coefficient (R2) of 0.861. [ABSTRACT FROM AUTHOR]

Clay minerals are one of the most abundant and crucial structural materials of the Earth’s crust, playing a significant role in many aspects of life. The present study aims to critically investigate the presence of microorganisms within different clayey soil samples. Microorganisms are ubiquitous by nature due to their natural ability to adapt to different habitats. Bacteria and Archea are the most abundant microorganisms in the soil and serve many important roles like nitrogen fixation. Fungi are also an integral part of the soil micro flora as they serve as food sources to other organisms as well as facilitate as layer organisms with beneficial relationships to plants. The continued evolution of man and subsequent use of clayey soils in areas such as pottery, cosmetics, engineering and geophagia brings into question whether microorganisms are harmful. Soil samples with high amounts of fine particles and colloidal substances were studied while taking into account the identified hydrated aluminosilicates and their roles in bioavailability. The study also investigated the possible types of microbial flora associated with each type of clayey soil as well as their functions within the human body. Considering the diverse origin of these microorganisms, we discuss their modes of attachment to clayey soils with the aim of minimising their transmission to humans. [ABSTRACT FROM AUTHOR]

Polysulphone/clay ion-exchange membranes were prepared by the phase inversion method using N-methyl-2 pyrrolidone as solvent. The aims of this work were to synthesize and investigate the effect of different natural clays from different locations on the morphology, hydrophilicity, structure, swellability, metal extraction from water and ion-exchange capacity (IEC) of the membranes prepared. The characterization techniques used were scanning electron microscopy, X‐ray diffractometry, Fourier transform infra-red spectroscopy and contact angle. The clays from locations 1 (N4) and 2 (N6) had a good dispersion in the polysulphone matrix and exhibited high IEC, swellability and hydrophilicity. The 2θof the polysulphone/clay membranes compared to polysulphone membrane was lower, indicating an increase in thed-spacing between layers of the clays and also intercalation of clay layer silicates in the polymer matrix. Extraction/adsorption of Pb2+by all the tested membranes was faster (10 min) compared to Cu2+, and it was approximately 100%. [ABSTRACT FROM AUTHOR]

The pervaporation (PV) performance of poly (vinyl alcohol) (PVA) is enhanced by the addition of natural clay clinoptilolite into it. Nanocomposites of glutaraldehyde cross-linked (in situ) PVA/clinoptilolite membranes were prepared by solution casting technique to investigate the water flux, selectivity, perm selectivity and enrichment factor. PV experiments using clay incorporated membrane matrix (CIMM) have been performed at 30, 40 and 50°C to separate water–isopropanol/ethanol feed mixtures containing 10–40 wt. % of water. These membranes were characterized by universal testing machine to understand the mechanical strength. The morphological analysis has been studied using scanning electron microscopy. The high content (5 and 10%) of clay in the CIMM extracts water efficiently on the permeate side with high selectivity. The hydrophilic nature of clay and the formation of CIMM are responsible to offer such increased separation of water over the organic components of the feed mixtures. [ABSTRACT FROM PUBLISHER]

In present investigation, a series of hydrogels, composed with Surfactant and poly(Acrylamide-co-Potassium acrylate), using Ammonium per sulfate(APS)/N,N,N 1 , N 1 -tetram ethylethylene diamine (TMEDA) initiating system and N,N 1-methylenebisacrlyamide (MBA) as crosslinker. The prepared hydrogel was characterized by using Fourier transform infrared spectroscopy (FTIR), Thermo gravimetric analysis (TGA), Scanning electron microscopy (SEM). The controlled release characteristics of the matrices for Triprolidene hydrochloride (TH) were investigated in pH 7.4 media. Drug was released in a controlled manner up to 1400 min. [ABSTRACT FROM AUTHOR]