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In this study, microcrystalline cellulose (MCC) was isolated from walnut and apricot shells (WS and AS) as agricultural wastes in order to use it as reinforcement in polymer composites. The microcrystalline cellulose was extracted by alkaline treatment and bleached by peroxide as an environmentally friendly treatment, called walnut cellulose (WC) and apricot cellulose (AC). The chemical composition of the samples was set according to the Technical Association of Pulp and Paper Industry (TAPP). After treatments, the alpha-cellulose content increased by about 23 % for the two used cellulose sources. The structural and morphological properties of the samples were investigated by Fourier transform infrared spectroscopy in the attenuated total reflectance mode (ATR-FTIR), optical microscopy (OM), X-ray diffraction and scanning electron microscopy (SEM). The crystallinity index values evaluated for WC and AC via X-ray diffraction were 86.4 and 80.3 %, respectively. The alkaline soluble fractions of walnut (ASW) and apricot (ASA) shells were recovered and characterized by OM and ATR-FTIR spectroscopy. Furthermore, their chemical composition was analyzed. The characterization and the properties of the WC and AC were similar to those of commercial MCC and MCC prepared in the literature from wood and some agricultural wastes.

In this study, the degradation of Azithromycin (AZM) by Fenton oxidation process (H2O2/Fe2+) was examined. The experiments were carried out in a batch reactor at ambient temperature and the efficiency of this treatment was monitored by analysing the overall parameter chemical oxygen demand (COD). Efficacy of Fenton's reagent for AZM degradation was studied concerning the process variables including (A) pH, (B) [H2O2]/[AZM], and (C) [H2O2]/[Fe2+]. The effect of these process variables and the interaction amongst each other was studied by a general full factorial design (GFFD) (3-level 3-factor) and response surface methodology, Box-Behnken design (BBD) was used to optimize this process. Additionally, a comparative analysis was conducted to assess the effectiveness of the GFFD and BBD methods in predicting COD removal. According to results of the analysis of variance ANOVA for COD removal efficiency by GFFD model, the model is suggested to be significant by the model F-value of 4.69. The accepted model was fit with an R-square of 0.91, in order to simulate the reaction over the selected ranges of the process variables, a BBD model was obtained, model statistics showed that a significant model was obtained, with an F-value of 64.82 for the corresponding probability of < 0.0005. The accepted model was fit with an R-square of 0.9942 and an adjusted R-square of 0.9798. Based on the optimized of the two models, the ideal process conditions were determined as pH = 2.5, [H2O2]/[AZM] = 145, and [H2O2]/[Fe2+] = 8., during a 90 min reaction time, the COD elimination rate is 94.13%. The results obtained from this study offer valuable insights for optimizing the Fenton process and achieving efficient degradation of AZM, thereby contributing to the field of wastewater treatment and environmental remediation. [ABSTRACT FROM AUTHOR]

The aim of this paper is the determination of the migration and biodegradation of the PVC additives in the soil. Epoxidized Sunflower Oil (ESO) was used as a thermal organic co-stabilizer for PVC; it was obtained by epoxidation of commercial sunflower oil. Two plasticizers were used: dioctyl phthalate (DOP) and diisononyl adipate (DINA). A natural aging test on site in a garden soil (Tizi Ouzou, Algeria) of the PVC samples was investigated for 6 months. The samples were characterized by Fourier transform infrared (FTIR).The morphological changes were followed by scanning electron microscopy (SEM). The evolution of the bacterial growth, identification using biochemical tests, variation of pH and variation of mass were investigated. The results showed that the nature of the plasticizer and heat stabilizer affects the properties of PVC as well as the phenomena of migration and biodegradation. [ABSTRACT FROM AUTHOR]

This article details our work in studying the plasticization of Poly(vinyl chloride) (PVC)/Polymethyl methacrylate (PMMA) blends with bio‐based acetyl tributyl citrate (ATBC) in place of conventional plasticizers such as di(2‐ethylhexyl) phthalate. PMMA was blended with PVC in various ratios from 0 to 100 wt% by melt compounding with or without the plasticizer ATBC. Both the glass transition temperatures of the blends (differential scanning calorimetry) and Tα (dynamic mechanical thermal analysis) are consistent with a miscibility of the components, and Fourier transforms infrared spectroscopy studies show that there are specific interactions in the PVC/PMMA blends favoring the miscibility. The thermal degradation of the blends was studied by thermogravimetric analysis that shows the thermal degradation of rigid and plasticized PVC/PMMA is a process composed of two‐steps and that PMMA exercises a stabilizing effect on the thermal degradation of PVC during the first step by decreasing the rate of dehydrochlorination. J. VINYL ADDIT. TECHNOL., 25:E73–E82, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The main purpose of this work was to evaluate the long term performance of butt welded polyethylene (PE) pipes in comparison to non-welded counterparts. Therefore, old welded PE pipes with different ages that had been used in Algerian gas distribution systems for up to 30 years were investigated. Samples prepared by butt welding of unaged pipes were used as reference. Crystallinity, melt rheology and thermal stability of pipes materials were examined at the weld zone and at the pipe wall. In order to assess the mechanical strength of welds, tensile test was conducted on both welded and unwelded specimens and the results of the strain to failure were considered for the determination of the weld factor. Compared to the reference, the results revealed that the crystallinity of PE materials at the weld zone was not affected by ageing as at the pipe wall. However, a slight decrease of the melt viscosity was observed for both welded and non-welded samples. The welds were found to be more sensitive to thermal and oxidative degradation than the parent pipes while the remaining amount of antioxidants was sufficient for service continuation. The tensile results indicate that welds strength were almost unaffected by ageing. [ABSTRACT FROM AUTHOR]