Assessment of Potential Use of a Composite Based on Polyester Textile Waste as Packing Elements of a Trickle Bed Bioreactor.

Biological wastewater treatment using trickle bed reactors is a commonly known and used solution. One of the key elements of the proper operation of the trickle bed bioreactor is the appropriate selection of biofilm support elements. The respective properties of the bioreactor packing media used can influence, among other things, the efficiency of the treatment process. In this study, the possibility of polyester waste material usage for the preparation of the biofilm support elements was tested. The following properties were checked: adsorption capacity, swelling, surface morphology, microbicidal properties, as well as the possibility of their use in biological wastewater treatment. The tested elements did not adsorb copper nor showed microbicidal properties for bacterial strains Escherichia coli and Staphylococcus aureus as well as fungal strains Aspergillus niger and Chaetomium globosum. The hydrophilic and rough nature of the element surface was found to provide a friendly support for biofilm formation. The durability of the elements before and after their application in the biological treatment process was confirmed by performing tests such as compressive strength, FTIR analysis, hardness analysis and specific surface area measurement. The research confirmed the applicability of the packing elements based on polyester textile waste to the treatment of textile wastewater. The treatment efficiency of the model wastewater stream was above 90%, while in the case of a stream containing 60% actual industrial wastewater it was above 80%. The proposed solution enables the simultaneous management of textile waste and wastewater treatment, which is consistent with the principles of a circular economy. The selected waste raw material is a cheap and easily available material, and the use of the developed packing elements will reduce the amount of polyester materials ending up in landfills.

Biochemical Approach to Poly(Lactide)-Copper Composite-Impact on Blood Coagulation Processes.

The paper presents the investigation of the biological properties of Poly(Lactide)-Copper composite material obtained by sputter deposition of copper onto Poly(lactide) melt-blown nonwoven fabrics. The functionalized composite material was subjected to microbial activity tests against colonies of Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria, Chaetomium globosum and Candida albicans fungal mold species and biochemical-hematological tests including the evaluation of the Activated Partial Thromboplastin Time, Prothrombin Time, Thrombin Time and electron microscopy fibrin network imaging. The substantial antimicrobial and antifungal activities of the Poly(Lactide)-Copper composite suggests potential applications as an antibacterial/antifungal material. The unmodified Poly(Lactide) fabric showed accelerated human blood plasma clotting in the intrinsic pathway, while copper plating abolished this effect. Unmodified PLA itself could be used for the preparation of wound dressing materials, accelerating coagulation in the case of hemorrhages, and its modifications with the use of various metals might be applied as new customized materials where blood coagulation process could be well controlled, yielding additional anti-pathogen effects.

Impact of Polymer Membrane Properties on the Removal of Pharmaceuticals.

The influence of various factors on the removal efficiency of selected pharmaceuticals by membrane filtration was investigated. Several commercial polymer membranes were used for nanofiltration (NF) from various manufacturers. The studies were conducted for ibuprofen (IBF), amoxicillin (AMX), diclofenac (DCF), tetracycline (TRC), salicylic acid (SA) and acetylsalicylic acid (ASA). The influence of the structure and properties of the tested compounds on the retention coefficient and filtration rate was investigated. The influence of pH on the filtration parameters was also checked. The properties of selected membranes influencing the retention of pharmaceuticals and filtrate flux were analysed. An extensive analysis of the retention coefficients dependence on the contact angle and surface free energy was performed. It was found that there is a correlation between the hydrophilicity of the membrane and the effectiveness and efficiency of the membrane. As the contact angle of membrane increased, the flow rate of the filtrate stream increased, while the retention coefficient decreased. The studies showed that the best separation efficiency was achieved for compounds with a molecular weight (MW) greater than 300 g/mol. During the filtration of pharmaceuticals with MW ranging from 300 to 450 g/mol, the type of membrane used practically did not affect the filtration efficiency and a high degree of retention was achieved. In the case of low MW molecules (SA and ASA), a significant decrease in the separation efficiency during the process was noted.

Photodegradation and ozonation of ibuprofen derivatives in the water environment: Kinetics approach and assessment of mineralization and biodegradability.

This article presents the results of studies on the degradation of ibuprofen transformation products: 1-hydroxyibuprofen (1OHIBF), 4-ethylbenzaldehyde (4EBA), 1-[4-(2-methylpropyl)phenyl]ethan-1-ol (MPPE) in water. To the best of our knowledge, this is the first paper where the ozonation and photodegradation (VIS and UV photolysis, degradation in H2O2/UV system, photosensitized oxidation) of 1OHIBF, 4EBA and MPPE are reported. The processes were performed in demineralized and natural river water. The influence of various reaction parameters on the removal degree was checked. Both, photolysis under VIS light and photosensitized oxidation of target compounds are very low-efficient processes. Ozonation and degradation in H2O2/UV system are effective methods for ibuprofen derivatives degradation. Components present in river water reduced removal degree of investigated compounds during ozonation and degradation in H2O2/UV system. The biodegradability assessment using the Average Oxidation State (AOS) and COD/TOC ratio proved the formation of more oxidized by-products during both processes. The determined second-order rate constants for ozone reaction with 1OHIBF, 4EBA and MPPE are 0.1 ± 0.01, 10.95 ± 1.36 and 3.04 ± 0.33 M-1 s-1, respectively. The calculated reaction rate constants of hydroxyl radicals with MPPE, 4EBA and 1OHIBF are 3.57 × 109, 6.83 × 109 and 1.06 × 109 M-1 s-1, respectively.

Removal of Organic Compounds with an Amino Group during the Nanofiltration Process.

The research covered the process of nanofiltration of low molecular weight organic compounds in aqueous solution. The article presents the results of experiments on membrane filtration of compounds containing amino groups in the aromatic ring and comparing them with the results for compounds without amino groups. The research was carried out for several commercial polymer membranes: HL, TS40, TS80, DL from various manufacturers. It has been shown that the presence of the amino group and its position in relation to the carboxyl group in the molecule affects the retention in the nanofiltration process. The research also included the oxidation products of selected pharmaceuticals. It has been shown that 4-Amino-3,5-dichlorophenol-a oxidation product of diclofenac and 4-ethylbenzaldehyde-a oxidation product of IBU, show poor separation efficiency on the selected commercial membranes, regardless of the pH value and the presence of natural organic matter (NOM). It has been shown that pre-ozonation of natural river water can improve the retention of pollutants removed.

Integration of nanofiltration and biological degradation of textile wastewater containing azo dye.

The anaerobic biological azo dyes reduction process was successfully applied to decolourization of the concentrates from the nanofiltration treatment of real textile effluents. The anaerobic phase was followed by aerobic oxidation aimed at the destruction of the aromatic amine released from azo dye. In the first experiment sequential batch reactor (SBR) combining both the anaerobic and aerobic phase in one unit was used. In the second one the anaerobic stage was separated from the aerobic one. The anaerobic phase fulfilled its aim (decolourization) in both systems (over 90%). In opposite, the aromatic amine was completely degraded in the aerobic reactor (two-sludge system), whereas the orthanilic acid was not degraded (during the aerobic phase) in SBR reactor. The COD reduction was also higher in the two-sludge system than in SBR.