34 research outputs found
Preparation and Characterization of Polyanhydride Terminated with Oleic Acid Extracted from Olive Mills Waste
No full textValorizing the fatty content of agricultural waste in material synthesis is an interesting topic. This work focused on utilizing oleic acid from the solid waste of olive mills in Saudi Arabia to synthesize biodegradable polyanhydrides based on sebacic acid which terminated with different concentrations of fatty acid (10, 30, 50, and 70 wt%), then characterize the final polymer samples and study the effects of termination on polyanhydrides properties, such as molecular weight and degradation profile. The fatty content of the solid waste was extracted, purified, and analyzed prior to and after separating the saturated and unsaturated fractions by urea crystallization, then the microwave-assisted melt polycondensation technique was used in the synthesis of the final polymers. Molecular weights were determined by gel permeation chromatography (GPC), and the degradation profile of the prepared samples was examined by determining the weight loss percentage of the polymer mass and FT-IR scanning for the anhydride bond before and after sample degradation. Results showed a linear degradation profile for most samples with no significant change in the molecular weights due to termination
Synthesis of Carbon Microspheres from Inedible Crystallized Date Palm Molasses: Influence of Temperature and Reaction Time
No full textIn this work, carbon microspheres (CMs) were prepared by hydrothermal carbonization (HTC) of inedible crystallized date palm molasses. The effects of temperature and reaction time on the prepared materials were studied. Experiments were carried out at different temperatures (180, 200, 230 and 250 °C) with reaction times ranging from 2 to 10 h. It was found that temperature had the greatest influence on the mass yield of the CMs. No solid products were observed at a temperature of 180 °C and a reaction time less than 2 h. The highest yield was found to be 40.4% at 250 °C and a reaction time of 6 h. The results show that the CMs produced were approximately 5–9 μm in diameter. The results also show that the largest diameter of the CMs (8.9 μm) was obtained at a temperature of 250 °C and a reaction time of 6 h. Nonetheless, if the reaction time was extended beyond 6 h at 250 °C, the CMs fused and their shapes were deformed (non-spherical shapes). The synthesized materials were characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Branuer-Emmett-Teller (BET) and thermogravimetric analysis (TGA). BET surface areas for the four samples were found to be less than 1 m2/g. The methylene blue adsorption studies indicated that the equilibrium adsorption capacity was reached after 15 min, with a maximum adsorption capacity of 12 mg/g. The recycling of date palm molasses (a known processed waste) to generate a useable carbon microsphere represents a beneficial step in the application of sustainable processing industries in the Middle East
Conductive Plastics from Al Platelets in a PBT-PET Polyester Blend Having Co-Continuous Morphology
No full textConductive plastics are made by placing conductive fillers in polymer matrices. It is known that a conductive filler in a binary polymer blend with a co-continuous morphology is more effective than in a single polymer, because it aids the formation of a ‘segregated conductive network’. We embedded a relatively low-cost conductive filler, aluminium nano platelets, in a 60/40 PBT/PET polymer blend. While 25 vol.% of the Al nanoplatelets when placed in a single polymer (PET) gave a material with the resistivity of an insulator (1014 Ωcm), the same Al nano platelets in the 60/40 PBT/PET blend reduced the resistivity to 7.2 × 107 Ωcm, which is in the category of an electrostatic charge dissipation material. While PET tends to give amorphous articles, the 60/40 PBT/PET blends crystallised in the time scale of the injection moulding and hence the conductive articles had dimensional stability above the Tg of PET
Date Palm Leaflet-Derived Carbon Microspheres Activated Using Phosphoric Acid for Efficient Lead (II) Adsorption
No full textThe removal of lead metals from wastewater was carried out with carbon microspheres (CMs) prepared from date palm leaflets using a hydrothermal carbonization process (HTC). The prepared CMs were subsequently activated with phosphoric acid using the incipient wetness impregnation method. The prepared sample had a low Brunauer–Emmet–Teller (BET) surface area of 2.21 m2·g−1, which increased substantially to 808 m2·g−1 after the activation process. Various characterization techniques, such as scanning electron microscopy, BET analysis, Fourier transform infrared, and elemental analysis (CHNS), were used to evaluate the morphological structure and physico-chemical properties of the CMs before and after activation. The increase in surface area is an indicator of the activation process, which enhances the absorption properties of the material. The results demonstrated that the activated CMs had a notable adsorption capacity, with a maximum adsorption capacity of 136 mg·g−1 for lead (II) ions. This finding suggests that the activated CMs are highly effective in removing lead pollutants from water. This research underscores the promise of utilizing activated carbon materials extracted from palm leaflets as an eco-friendly method with high potential for water purification, specifically in eliminating heavy metal pollutants, particularly lead (II), contributing to sustainability through biomass reuse
Green synthesis of strontium stannate nanorods using extract of Juniperus communis L.: Structural characterization and evaluation of antibacterial, antifungal, and antioxidant activity
No full textAbstract Strontium stannate nanorods (SrSnO3 NRs) were synthesized in the present study via a green, sustainable, and cheap method with leaf extract from Juniperus communis L. UV-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray analysis (EDAX) were performed to investigate the SrSnO3 NRs. The particle size distribution (PSD) of SrSnO3 NRs characterized by using dynamic light scattering (DLS) analysis. The UV-visible spectra of the synthesized SrSnO3 NRs showed an absorption peak at 279 nm. SEM images confirmed that SrSnO3 NRs, which have an average size of about 29 nm, include a bunch of rod-like structure. In addition, the as-formed SrSnO3 NRs demonstrated excellent antibacterial activity against the bacteria Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli. The synthesized SrSnO3 nanorods also exhibited a significant amount of antioxidant activity. It is also an attractive biocompatible choice for pharmacological and medical applications
Preparation of Bio-Based Polyurethane Coating from Citrullus colocynthis Seed Oil: Characterization and Corrosion Performance
No full textIn this study, a new epoxidized oil from Citrullus colocynthis seed oil (CCSO) was obtained for a potential application in the formulation of polyurethane coatings. Initially, the fatty acid composition of CCSO was determined by gas chromatography–mass spectrometry (GC–MS). Subsequently, the epoxidation of CCSO was performed with in situ generated peracetic acid, which was formed with hydrogen peroxide (30 wt.%) and glacial acetic acid and catalyzed with sulfuric acid. The reaction was continued at a molar ratio of 1.50:1.0 of hydrogen peroxide to double bond (H2O2:DB) for 6 h at a controlled temperature of 60 °C. The resulting epoxidized oil was then used to produce a bio-based polyol by hydroxylation. The molar ratio of epoxy groups to methanol and distilled water was maintained at 1:11:2, and the reaction was carried out for 2 h at a controlled temperature of 65 °C. The major functional groups of the epoxidized oil and its polyol were validated by Fourier-transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopies. A polyurethane (PU) coating was produced from the synthesized polyol and 3HDI isocyanurate, keeping the molar ratio of NCO:OH at 1:1. The resulting PU coating was then applied to glass and aluminum panels (Al 1001). After the film was cured, the properties of the PU coating were evaluated using various techniques including pencil hardness, pendulum hardness, adhesion, gloss, chemical resistance, and EIS tests. The results show that the PU coating obtained from CCSO is a promising new raw material for coating applications
Impact of Natural and Synthetic Antioxidants on the Stability of High-Density Polyethylene
No full textHigh-Density Polyethylene (HDPE) plays a crucial role in the life of every human being due to its properties such as chemical resistance, light weight, and ease of forming, among others. Its usage ranges from bottles for beverages and other liquids, to pipes, wire and cable insulation, and prosthetics. As it undergoes several thermal cycles during its life cycle, it is essential to maintain its qualities, even after undergoing thermal and thermo-oxidative degradation. Here, various dosages of synthetic (Irganox 1010) and natural (vitamin E) antioxidants are added to HDPE formulations to study their impacts on HDPE stability. The antioxidants are mixed physically with HDPE before the mixtures are melt-mixed three times to represent their life cycles. Samples are taken after each time and used to analyze the molecular weight distribution, rheological behavior, mechanical properties, and thermal stability. The results show that vitamin E is superior to Irganox 1010 in these tests, as vitamin E performance exceeds that of Irganox 1010, even at lower doses. The only drawback of using vitamin E is the yellow color it causes, which may necessitate the addition of another additive to enhance the color stability of HDPE in color-sensitive applications
Removal of methyl violet using synthesizing silver nanoparticles from plant-based biomass: Adsorption and photocatalytic degradation
No full textThis research presents an innovative and environmentally friendly method for the synthesis of silver nanoparticles (AgNPs) using Conocarpus fruits, with the aim of improving the adsorption and photocatalytic degradation of methylene violet (MV) in wastewater treatment applications. The study systematically investigated the photocatalytic performance of AgNPs prepared under different concentrations of silver nitrate (AgNO3) and different pH values, as well as the operating efficiency of a photocatalytic reactor. A comprehensive analysis of various synthesis parameters was carried out, including the manipulation of silver nitrate concentrations and pH values, employing a variety of characterization techniques such as scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and atomic force microscopy (AFM). The findings revealed that the degradation of MV was remarkably fast and reached a remarkable removal efficiency of 99.86 % within the first hour by adsorption and photocatalytic processes under optimal conditions (pH = 8, 1 g sample and MV concentration of 50 ppm). The maximum adsorption capacity was determined to be 49.63 mg/g. Moreover, the AgNPs showed an impressive degradation rate of 100 % within two hours of UV light irradiation, highlighting the synergistic effects of AgNPs in enhancing both adsorption and photocatalytic activity. This study not only highlights the viability of Conocarpus fruits as a sustainable source for AgNP synthesis, but also emphasizes the potential of AgNPs in advancing wastewater treatment applications
