Removal of Organic Impurities from Water Using a Reactor with Photoactive Refill

The aim of the presented work was the removal of phenol from water using a reactor with photoactive refill. Titanium dioxide (Chemical Factory “Police” Poland) was immobilized on the base material as a thin layer from the alcoholic suspension followed by thermal stabilization. The glass fabric was applied as a support for the titania coating. The results of studies revealed that the titania coatings show a high photocatalytic activity toward the phenol decomposition in water. The complete removal of phenol was achieved in the relatively short time of 23 hours. The prepared coatings exhibit high stability in repeated cycles of water treatment. The proposed reactor with photoactive refill solves the problem of necessity of replacement of the reactor or the parts of the reactor when the photocatalysts activity decreases. In the case of activity drop of the photocatalyst, only the photoactive refill can be easily replaced

Degradation of sertraline in water by suspended and supported TiO2

Pharmaceutical pollutants have been detected in many countries in surface and ground water after treatment in wastewater treatment plants. The presented studies concern the photocatalytic removal of one of SSRI antidepressants - sertraline from water using TiO2 photocatalyst. The process was conducted using two laboratory installations with periodic and flow reactors. Two forms of TiO2 was used in the photocatalytic reactions: suspended and supported onto a glass fabric. The studies shown that with increasing initial concentration of pharmaceutical, photoactivity decreases. For the initial concentration of 0.025 g/dm3, the best results – 94% removal – was achieved for the process conducted in the periodic reactor with TiO2 supported onto a glass fabric

Simultaneous photooxidation and photoreduction of phenol and Cr(VI) ions using titania modified with nanosilica

The photocatalytic process of phenol oxidation and Cr(VI) reduction in the presence of nano-silica modified titania was carried out. The activity of composites was tested using two different light sources. The photocatalysts with 10% of nanosilica showed the highest activity. The calcination temperature (200–800 °C) significantly determined the sensitivity of the obtained materials to the light source used. Photocatalysts alternately adsorbed and desorbed Cr(VI) ions from the reaction mixture during irradiation. In the one-component mixture, complete oxidation of phenol was observed using material calcined at 650 °C, after 3 h of UV-VIS irradiation. In the reaction mixture of Cr(VI) and phenol, the highest activity was demonstrated by photocatalyst calcined at 300 °C. The concentration of phenol decreased in proportion to the decrease of chromium ions. The obtained titania-silica composites showed oxidizing properties towards phenol and reductive properties toward Cr(VI) ions

Thermally modified titania photocatalysts for phenol removal from water

Two kinds of titanium dioxide were used as starting materials for thermal modification: Tytanpol A11 supplied by Chemical Factory “Police” S.A. (Poland) and Degussa P25 supplied by Degussa AG (Germany). The photocatalytic activity of titania materials modified by thermal treatment was tested in the reaction of photocatalytic oxidation of phenol. It was found that the highest activity in the reaction of photocatalytic decomposition of phenol, in case of Tytanpol A11, shows the samples of material modified at temperatures of 700 and 750°C. These catalysts were more active than untreated A11, whereas materials modified at higher temperatures show lower activity. In the case of P25, all thermally treated materials were less active than the unmodified material. The photocatalyst samples were characterized by UV-Vis/DR, FTIR/DRS, and XRD methods

Stability of selenium diet supplement

Selenium is one of the trace elements playing a crucial role in a proper function of living organisms. Selenium intake varies, largely based on the selenium content of food. The daily Se intake recommended for adults amounts to 55 μg per day. The mean level of selenium in the population varies considerably between countries. Recent studies on the selenium dietary intakes in Poland showed that it is not sufficient to meet the daily requirement for this microelement so it is strongly recommended to employ selenium supplementation. The commercial product SEL-BRCA1® being a selenium diet supplement was subjected to chemical and microbial analysis to determine its stability in storage time and conditions. Basing on the obtained results it can be stated that the stability of studied supplement, stored in the closed bottles, can be confirmed for the period of time up to 45 months after the production date and it is not recommended to store opened bottles for the period of time longer than 12 months. The studied supplement showed a very high microbial stability what underscores its usefulness as human medicines

The study of glycerol-based fermentation and broth downstream by nanofiltration

In this work, the glycerol fermentation was carried out using Citrobacter freundii bacteria. The influence of glycerol and metabolites concentrations, and the pH changes on the efficiency of 1,3-propanediol production, during batch and fed-batch processes, was presented. The nanofiltration was used for the separation of obtained post-fermentation solutions. The resulted 1,3-PD solutions were significantly desalted, which may facilitate further downstream processes during 1,3-PD production

The study of glycerol-based fermentation and broth downstream by nanofiltration

In this work, the glycerol fermentation was carried out using Citrobacter freundii bacteria. The influence of glycerol and metabolites concentrations, and the pH changes on the efficiency of 1,3-propanediol production, during batch and fed-batch processes, was presented. The nanofiltration was used for the separation of obtained post-fermentation solutions. The resulted 1,3-PD solutions were significantly desalted, which may facilitate further downstream processes during 1,3-PD production

The study of glycerol-based fermentation and broth downstream by nanofiltration

In this work, the glycerol fermentation was carried out using Citrobacter freundii bacteria. The influence of glycerol and metabolites concentrations, and the pH changes on the efficiency of 1,3-propanediol production, during batch and fed-batch processes, was presented. The nanofiltration was used for the separation of obtained post-fermentation solutions. The resulted 1,3-PD solutions were significantly desalted, which may facilitate further downstream processes during 1,3-PD production

On the characteristic and stability of iron diet supplements

The iron diet supplements: AproFER 1000 and AproTHEM were subjected to various chemical, microbial and magnetic analysis. The microbial analysis revealed no presence of pathogenic bacteria in the studied products. No significant changes in iron content or forms (bivalent/trivalent) were observed in EPR analysis of supplements stored at different conditions for a long period of time. The chemical and magnetic analysis showed that both AproFER 1000 and AproTHEM contain a high concentration of bivalent iron so they can be used as an iron diet supplements