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The properties of recycled low temperature biodegradable polycaprolactone-based thermoplastic polyurethane (rTPU), filled with different types of organically modified montmorillonite (MMT) prepared by two-roll milling, were studied. The dependence of rTPU properties on the mastication time and clays content was determined by various structural and physical testing methods. Results show that the melt flow and mechanical properties of rTPU deteriorate with increasing of mastication time, but thermal properties were affected only slightly. rTPU/MMT composites show exfoliated or intercalated structures depending on the nature of organic modifier of clay. MMT reduces slightly rTPU tensile and melt flow properties, but accelerates hydrolytic degradation process. During degradation the weight loss and polydispersity increase significantly in the presence of MMT, but it does not accelerate crystallinity changes. The degradation of rTPU composites with higher hydrophilicity organoclays proceeds faster than that with hydrophobic ones due to the relatively higher interaction with polymer matrix.

In the petroleum industry during a catalytic cracking process, the used zeolitic catalyst becomes waste. this article investigated the sorption capacities of ammonium ions from aqueous solutions onto the previously mentioned zeolitic waste by batch experiments. Three types of zeolitic waste were used: unmodified zeolitic waste with two different particle size distributions and H 2 o 2-modified zeolitic waste. Several techniques, including X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) multilayer adsorption theory measurements, and X-ray fluorescence analysis (XRF) were used to demonstrate experimentally that the zeolitic waste could be used as a sorbent for the water decontamination of NH 4 + ions. The morphology of zeolitic waste investigated by scanning electron microscopy (SEM) revealed particles with a spherical shape. The nitrogen adsorption-desorption isotherms showed an isotherm mixture of types I (pure microporous) and IV (mesoporous). This suggested that the investigated zeolitic materials were mesoporous (4.84 nm) and microporous (0.852 nm), as well as containing slit/cylindric pores, according to a quench solid density functional theory (QSDFT) adsorption branch model. Zeolitic waste from the oil industry showed good NH 4 + sorption properties (removal efficiency of 72%), thus becoming a potential adsorbent to be used in the treatment of contaminated aqueous effluents polluted with ammonium ions. Simultaneous waste and water decontamination can be achieved, providing a new tool and enhanced capabilities for environmental remediation. Ammonium (NH 4 +) is one of the common form of reactive nitrogen in wastewater 1 , and its contamination in fish causes serious health problems due to its high toxicity. The technologies for ammonia removal from wastewater are based on physicochemical and biochemical treatment methods 2. One of these treatment methods is adsorption, which is a low-cost process. Different adsorbents, such as wheat straw biochars, pine sawdust or zeolites, can be effective in adsorbing ammonium in wastewater 3-13. Yang et al. 4 used some natural adsorbents such as pine sawdust and wheat straw biochars for the ammonium removal in wastewater. It was concluded that biochars can be efficient absorbents for NH4 + removal from aqueous solutions. Tian et al. 5 synthesized a new sorbent using modified coal cinders and zeolite powders. This sorbent has been shown to be a good material for the removal of ammonia nitrogen. The removal efficiency of ammonia nitrogen was 67.3% and 71.3%. The inflow concentrations of ammonia nitrogen were obtained under the experimental conditions where chemical oxygen demand under a water flow of 10 L/h. Yin et al. 6 used NaCl-modified clinoptilolite as adsorbent for the nitrogen removal. Results in a current batch study provided that the maximum ammonium sorption capacity of clinoptilolite was in the range of 6.64 to 7.27 mg. N/g. The work reported by Sánchez-Hernández et al. 7 evaluated the use of NaP1 ze...

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