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ESTiG - Artigos em Revistas Não Indexados à WoS/Scopus

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http://hdl.handle.net/10198/14999

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Percorrer ESTiG - Artigos em Revistas Não Indexados à WoS/Scopus por Domínios Científicos e Tecnológicos (FOS) "Engenharia e Tecnologia::Engenharia Química"

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  • Chlorine reactivity with organic matter: a modelling approach for surface waters in Portugal and Angola
    Publication . Martins, Ramiro
    Water quality is an essential requirement for human consumption. One of the key quality criteria is the absence of bacterial contamination, necessitating disinfection as the final step in water treatment, which is commonly achieved through chlorination. During chlorination, chlorine is consumed through the oxidation of the organic compounds present in water. This study focused on examining chlorine consumption in raw water from the Bengo River (Angola) and water at the outlet of the Lever Water Treatment Plant (Portugal). Specifically, the decay kinetics of chlorine in water samples were investigated through a series of experiments. In the first series, the chlorine concentration was varied while maintaining a constant level of organic matter (expressed as oxidability using KMnO4) at temperatures of 25 and 35°C. In the second series, the chlorine concentration was held constant while the oxidability varied. Various kinetic models have been applied to the experimental data to describe the decay of chlorine and organic matter. The parallel first-order model yielded the most satisfactory representation of chlorine consumption kinetics.
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  • Industrial effluent remediation using aquatic mosses: an effective biosorption approach
    Publication . Martins, Ramiro
    Heavy metals in industrial wastewater pose significant environmental and public health threats. This study explored the use of the aquatic moss Fontinalis antipyretica as a natural biosorbent to eliminate cadmium (Cd²⁺) and lead (Pb²⁺) from simulated wastewater. The study assessed the impact of crucial factors such as initial pH, contact time, and metal ion concentration, utilizing a sorbent dose of 2 g L⁻¹. Optimal biosorption occurred at pH levels ranging from 4.0 to 6.0, achieving a maximum uptake capacity of 4.8 mg g⁻¹ for both metals at an initial 10 mg L⁻¹ concentration. At a concentration of 100 mg L⁻¹, the removal efficiency of Pb²⁺ exceeded 78%, demonstrating a stronger affinity for Pb. Among the kinetic models tested, the pseudo-second-order model best fit the experimental data (R² = 0.999), indicating that chemisorption was a key mechanism in the process. These results highlight the potential of Fontinalis antipyretica as an effective, cost-efficient, and environment-friendly method for treating metal-laden industrial effluents
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