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This paper presents the results of the possibility and effectiveness of PAHs removal from a model aqueous solution, during the sorption on the selected sorbents. Six PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene) listed by EPA for the analysis in the environmental samples were determined. Model aqueous solution was prepared with RESTEK 610 mix PAHs standard. After the sorption process, decrease in the concentration of individual hydrocarbons was observed. The removal percentage was dependent on the type of sorbent (quartz sand, mineral sorbent, activated carbon). The highest efficiency (98.1%) was observed for activated carbon.. The results shows that the sorption processes can be used in aqueous solutions treatment procedures.

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In this paper, coke wastewater that had passed through biological and integrated membrane processes (filtration on sand bed—reverse osmosis) was chosen to assess the phytotoxicity of selected industrial wastewater with regard to the test plant—Vicia faba. An innovative research technique in vitro test was conducted in a large scale phytothrone chamber on two matrices: cotton and Murashige and Skoog Basal Medium (MSBM). The toxicity of wastewater was evaluated for samples: (1) treated in the treatment plant by biological processes, (2) filtrated through a sand bed and filtrated (3) reverse osmosis (RO) membrane. The results showed that there is a noticeable correlation between increasing concentrations of wastewater and seed germination of the test plant. Although the wastewater collected from the coke plant was treated biologically, it showed very high levels of germination inhibition (90–98% for cotton matrix and 92–100% for MSBM matrix) and strong toxic effects. The wastewater collected from the coke plant showed a significantly greater phytotoxic effect compared with those obtained from the effluent treated on a sand bed and in RO. However, wastewater, even after treatment on a sand bed (reduction of COD—39%, TN—46%, TOC—42%, TC—47%, SS—50%, 16PAHs—53%), was still toxic and germination inhibition was in the range of 24–48% for the cotton matrix and 14–54% for the MSBM matrix. The toxicity of wastewater treated in the membrane process was the lowest (reduction of COD—85%, TN—95%, TOC—85%, TC—86%, SS—98%, 16PAHs—67%). The germination inhibition was in the range of 4–10% for the cotton matrix and 2–12% for the MSBM matrix. These samples are classified as non-toxic or slightly toxic to the model plant. The present study highlights the necessity of monitoring not only the basic physical and chemical indicators (including the level of toxic substances as PAHs), but also their effect on the test organisms in wastewater samples.

We synthesized oligomer mixtures of (2,4-dichlorophenoxy) acetyl-(R,S)-3-hydroxybutyric acid and (3,6-dichloro-2-methoxy) benzoyl-(R,S)-3-hydroxybutyric acid, transforming (2,4-dichlorophenoxy)acetic acid (2,4-D) and (3,6-dichloro-2-methoxy)benzoic acid (dicamba) into low volatile oligomers with greater lipophilicity than the parent acids. Synthesis of the functional oligomers was carried out via the ring-opening polymerization of (R,S)-β-butyrolactone initiated by (2,4-dichlorophenoxy) acetate or (3,6-dichloro-2-methoxy) benzoate potassium salts in the presence of bulky complexing agents. The 3-hydroxybutyric acid (3-HBA) oligomers were susceptible to (bio)degradation via ester bond hydrolysis, which enables controlled release of the active ingredient. For each 3-HBA oligomer mixture, we determined the molecular structure and molecular weight by means of size exclusion chromatography, proton magnetic resonance spectrometry, and electro-spray ionization mass spectrometry. In addition, we evaluated the herbicidal efficacy of the 3-HBA oligomers on several broad-leaved species and crop injury to winter wheat relative to conventionally formulated dimethyl ammonium (DMA) salts. The death of weeds treated with the 2,4-D and dicamba 3-HBA oligomers was delayed relative to that induced by the DMA salts. This delayed activity may be explained by the controlled release of the 3-HBA oligomers.

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