Filtration-sorption ability of nanofibre filters for removal of arsenic in water

abstract

English

Arsenic contaminated drinking water is a major problem in many parts of the world. An obvious health risk arises through consuming just this water, therefore, the elimination of arsenic constitutes an important step in water and wastewater treatment [1]. Numerous studies have proven that long-term exposure to arsenic in drinking water causes health problems: skin lesions (hyperpigmentation, hyperkeratosis), diseases affecting the blood vessels of the legs or feet, high blood pressure, reproductive disorders and cancer of the bladder, lungs, skin, kidney, nasal cavity, liver or prostate and other [2]. There are several different methods and techniques for removing arsenic in water. However, many of them have their limitations [3, 4]. Our research focuses on removing of arsenic from contaminated water via a microfiltration nanostructured membrane prepared from polymeric nanofibers materials [5, 6], applied in prospective combination with an inorganic sorption material (iron oxide). Membranes prepared from polyurethanes by electrospinning are preferably used. The sorption of nanostructured membranes during the filtration processes are studied in model water (distilled water contaminated by disodium hydrogen arsenate) and also in naturally contaminated mineral water. First, we made the sorption tests of arsenic to select the best nanofibrous materials. The arsenic sorption is the process of removing any arsenic already intercepted, influenced by the time during which the contaminated water is in contact with the nanofibers. Later we continued by filtration-sorption process and tested different type of filters: chopped, wound, layered and cylindrical filters. It was needed to design the arrangement of filtrate materials in the filtration apparatures so that the surfaces of the nanofibers could obtain the maximum contact with the arsenic contaminated water during a process. But only with the help of an inorganic sorption additives on the base of ferric oxide could be ensured elimination of arsenic in water below its limit value (10 μg/l). The different parameters as flow, pressure, time of filtration process were monitored too. The concentrations of eliminated arsenic (μg/l) in the contaminated water samples were monitored by atomic absorption spectroscopy. Filters from polyurethane demonstrated the selective sorption of arsenic in comparison with other elements as Fe, K, Na, Mg or Ca. Our results presented are applicable for preparing filters for selective removing of arsenic from contaminated mineral water that combine organic nanostructured microfilters and an inorganic adsorptive additive in their construction. These tested arrangements for removing arsenic in water should be also generating less toxic waste than the current methods and could represent an effective way of removing arsenic. But most important for the arsenic elimination in water is the arrangement and amount of the nanofibers, type of support and an inorganic sorbent too (Fig. 1). We proved the reproducibility of sorption in the mineral waters by a discontinuous test and by the continuous filtration process too. The results measured for the sorption activities of the model water were in good accordance with those for the naturally mineral sample.

Arsenic, Adsorptive filtration, Polyurethane, Drinking water

BERGEROVÁ, E.; KIMMER, D.; KOVAŘOVÁ, M.; LOVECKÁ, L.; VINCENT, I.; ADAMEC, V.; KÖBÖLOVÁ, K.; SEDLAŘÍK, V.

8. 10. 2020

Ústav polymérov, Slovenská Akadémia Vied

Smolenice

978-80-89841-14-1

XI. Slovensko - Česká konferencia POLYMERY 2020

1

68

69

100

http://polymer.sav.sk/polymery2020/documents/Kniha%20prispevkov_Polymery2020.pdf