Upcycling of Waste Polyethylene and Cement Kiln Dust to Produce Polymeric Composite Sheets Using Gamma Irradiation

Cement kiln dust (CKD) is a residue produced during the manufacture of cement that contains hazardous solid waste of high toxicity that affects the environment and public health. In this study, the possibility of using cement waste as a filler in the plastic and rubber industry was studied. Different concentrations of (CKD) and gamma irradiation on the mechanical, thermal stability of the prepared composites sheets were investigated. Different concentrations of (CKD) 10, 15, 20, 30, 35, and 40 wt % were prepared with double screw extrusion by mixing waste polyethylene (WPE), de-vulcanized rubber (DWR), and EPDM rubber. These prepared composites were irradiated with doses 25, 50, 75, 100, and 150 kGy to study the effect of radiation on the physical, mechanical properties, and thermal stability of the prepared composite sheets. The prepared composite sheets were characterized and verified by FTIR and soluble fractions. The morphology of the composite sheets was investigated by SEM. Mechanical and thermal properties were investigated to evaluate the possibility of its application in the plastic and rubber industry.

The Influence of Zinc Oxide with Carbon Nanotube Composite NanoMaterials on Antibacterial Activity

A novel hybrid substance, ZnO: MWCNT, are fabricated from prepared pellets using a pulsed laser ablation liquid technique at varied MWCNT concentrations (0, 3, 5, 10, and 15) wt%. The study cast at the effect of MWCNT concentration on the structure of prepared samples using FTIR and tested for different types of antimicrobial activity. From FTIR examination, one can observe that all the prepared ZnO: MWCNT samples with different concentrations have different types of band (stretching and bending). All the prepared composite samples with various concentrations have showed influence on different types of bacterial, however in general the annealing ZnO, MWCNT and the composite nanomaterial with 15%MWCNT have higher zone of antibacterial activity for studying types of bacterial inhibition.

Facile Synthesis of Cu-Zn Binary Oxide Coupled Cadmium Tungstate (Cu-ZnBO-Cp-CT) with Enhanced Performance of Dye Adsorption

This study reports the synthesis of copper–zinc binary oxide coupled cadmium tungstate through a simple bio-precipitation method followed by calcination at 600 °C and its adsorption application. The characterization analysis reveals that the prepared composite has low particles size (nano-range), high porosity, and functional groups on the surface. The calcination of sample at 600 °C causes some essential function groups to disappear on the surface. Prepared composite was found to be effective adsorptive material to treat Congo red dye in aqueous solution. 2.5 g L−1 dose of adsorbent could remove more than 99% Congo red dye from 10 mg L−1 solution and more than 80% Congo red dye from 60 mg L−1 aqueous solution. The maximum adsorption capacity of present adsorbent was calculated to be 19.6 mg Congo red per gram of adsorbent. Isotherms analysis suggested a physio-chemical adsorption process. Thermodynamic analysis revealed a exothermic and feasible adsorption process. Adsorption rate was well explained by pseudo second order kinetics. The rate determining step was intra-particle diffusion evaluated from the Weber-Morris plot. To assess the adsorption performance of present adsorbent for Congo red dye the partition coefficient and adsorption equilibrium capacity were compared with other adsorbents. The partition coefficient and adsorption equilibrium values for 10 mg L−1 aqueous solution were found to be approximately 83.3 mg g−1 µM−1 and 4.0 mg g−1 at 30 °C and 7.0 pH using 2.5 g L−1 adsorbent. The value of partition coefficient was found to be higher than previous reported zinc oxide coupled cadmium tungstate having partition coefficient = as 21.4 mg g−1 µM−1 at 30 °C and 7.0 pH using 2.0 g L−1 adsorbent (Fatima, B.; Siddiqui, S.I.; Nirala, R.K. et al., Environ. Poll. 2021, 271, 116401). These results suggested that present adsorption technology is efficient for wastewater treatment.

Recycling of buffing dust tanneries waste to prepare structural thermal insulation panels

Thermal insulation panels were prepared by mixing the buffing dust obtained from tanneries waste with the polystyrene. The ratio in weight percentage of buffing dust, polystyrene and blowing agent was 20:77:3 respectively in these panels. The samples were prepared in co-twine extruder at 210 oC. Different physico-chemical properties were investigated for these samples that are required to analyze the usability of a material for construction. The composite panels showed better thermal insulation characteristics than the simple polystyrene boards. This study demonstrated that prepared composite panels have good thermal conductivity (0.029 W/m-K at 27 oC), density (300 Kg/m3), compression strength (6.25 ton) and water absorption (7.5%) without degradation of mechanical properties. Thermogravimetric analysis depicted that composite panels were thermally stable from 200 oC to 412 oC. FTIR analysis showed that composite has carbonyl and free amino functional groups. The SEM study explained that voids were created in the composite and homogeneousity was decreased after the addition of buffing dust. The composite had 62% of carbon and 0.2% of chromium as determined by EDX analysis. The results suggested that the prepared composite panels can be used as thermal insulation boards in building sector which will help in the recycling of waste produced by leather industry and consequently a reduction in environmental pollution.

Thermal properties of epoxy nanoclay composite materials

Composite materials are an emerging topic for research as a new competitive material in engineering. New classes of composite material manufactured from particles, nanoparticles and resins, and have experienced efficient and economical for the development and also replacement of new as well as deteriorating structures. In this study epoxy-nanoclay composite materials with varying compositions of nanoclay compared with pure epoxy and epoxy with 10, 20, and 30 by weight fraction of nanoclay are prepared for better insulating materials. The various thermal properties of the material were analyzed to demonstrate that the the prepared composite is a good insulator. An increase in specific heat maximum by 11.26%, thermal stability by 58.82% results in decrease in thermal conductivity maximum by 25.65%, diffusivity to 46.8% and also co-efficient of thermal expansion with an increase in nanoclay proportion is observed. DSC, TGA and TMA are used for determining the thermal properties. SEM and EDS analysis were used to show homogeneous mixture of epoxy and nanoclay.

Manufacture of Shielding for Attenuation Ionization Ray by the Preparation of Nano Gadolinium Oxide with PMMA

In this research, the coefficient of linear absorption, Half-value layer and Effective atomic number of the composite material for gamma ray of gadolinium oxide with PMMA (Gd2O3- PMMA) for shields made with varying concentrations (10%, 20%, 30%, 40%) and varied thicknesses The impact of raising the shield thickness when the concentration of each thickness is increased. The gamma ray radiation source was Cs-137and Co-60 which have (activity 10 μci and energy of 0.662 MeV, activity 1μci and energies 1.173 -1.332 (MeV) were used in measurement, As an electrical system, a scinatelaion detector (NaI (Tl)) was utilized with a (2x2)" for ORTEC software program (Scintivision-Buffer) with an integrated measurement system. The results reveal that when the concentration of nano particle-gadolinium oxides raised and the thickness of the produced layer increased, the attenuation coefficient and effective atomic number values increased of the prepared composite However, as the concentration and thickness of the composite increased, the Half-value layer values dropped.

Effect of Laser Surface Heat Treatment on Wear and Hardness Resistance of Metal Matrix Composite from (Al- 6061+ SiC Particles)

In this paper, the effect of laser surface heat treatment on wear resistance and hardness of an aluminum alloy Al-6061 as a base material with different ratios of SiC particles as an additive was studied. The composite material was prepared from Al-6061 aluminum alloy and particles with a granular size of (10-70) μm with different weight ratios (15%, 12%, 9%, 6%, 3%), where the stirred plumbing technique was used to ensure An increase in the wettability of SiC particles in the base alloy fuse and the possibility of distributing it uniformly. The laser surface heat treatment of the composite material prepared using the Neodymium - YAG laser was performed with a power of 1J, a wavelength of 1.06 μm, a pulse time of 5 m sec, and a distance of 30 cm between the exit area of the laser from the system and the piece to be thermally treated. The results showed an improvement in the mechanical properties of the prepared composite material (hardness, wear resistance) after performing the surface heat treatment by laser. The increase in the hardness amount was 12.9% when adding 15% of particles to the base alloy. The results showed that the wear rate value decreases with increasing the added percentages of SiC particles. The results also showed that the surface heat treatment of the laser led to an improvement in the wear resistance of the prepared composite material and for all the added ratios of SiC particles at different loading pressures used and in close proportions. Also, the prepared samples were photographed using a regular optical microscope before and after the laser surface heat treatment.

Visible-Light-Driven Bio-Templated Magnetic Copper Oxide Composite for Heterogeneous Photo-Fenton Degradation of Tetracycline

The development of a visible-light-driven, reusable, and long-lasting catalyst for the heterogeneous photo-Fenton process is critical for practical application in the treatment of contaminated water. This study focuses on synthesizing a visible-light-driven heterogenous bio-templated magnetic copper oxide composite (Fe3O4/CuO/C) by a two-step process of bio-templating and hydrothermal processes. The prepared composite was characterized by field emission-scanning electron microscope (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), electrical impedance spectroscopy (EIS), and vibrating sample magnetometer (VSM). The results reveal that the prepared composite retains the template’s (corn stalk’s) original porous morphology, and a substantial amount of CuO and Fe3O4 particles are loaded onto the surface of the template. The prepared Fe3O4/CuO/C composite was employed as a catalyst for heterogeneous photo-Fenton degradation of tetracycline (TC) irradiated by visible light. The prepared Fe3O4/CuO/C catalyst has high efficiency towards TC degradation within 60 min across a wide pH range irradiated by visible light, which is attributed to its readily available interfacial boundaries, which significantly improves the movement of photoexcited electrons across various components of the prepared composite. The influence of other parameters such as initial H2O2 concentration, initial concentration of TC, and catalyst dosages was also studied. In addition to high efficiency, the prepared catalyst’s performance was sustained after five cycles, and its recovery is aided by the use of an external magnetic field. This research paper highlights the development of a heterogeneous catalyst for the elimination of refractory organic compounds in wastewater.

Optimisation of Tensile Strength and Weight Loss via Taguchi and Response Surface Method for Natural Rubber Latex Film Consisting Cassava Peel as a Bio-Based Filler

Disposal latex and synthetic rubber gloves is troublesome such that disposal via incineration and land fill may release poisonous gasses and contaminate soil and water, respectively. As solution to latex and synthetic rubber, biodegradable glove is extensively studied. A bio-based filler is extracted from food waste and blended into natural rubber latex (NRL) as a composite NRL. The effect of biodegradability of composite NRL was studied by varying the loading of bio-based filler in a form of starch dispersion and blended into NRL mixture. Herein some amount of starch can be extracted from cassava peel to be incorporated in NRL for a sustainable and yet biodegradable glove. Previous work on incorporation of cassava-peel filler in NRL has shown a biodegradability without compromising the pristine strength of NRL film at 50% loading starch. In this project, tensile strength and weight loss of prepared composite NRL films were optimised via Taguchi and Response Surface Method (RSM) by means of Design Expert software by varying starch/filler loading, curing temperature and curing drying duration. Due to inadequate data, the optimisation from that previous prepared composite NRL was compared with similar work which utilising NRL and bio-based filler. For Pulungan (2020) study, it can be concluded that the tensile strength of cassava peel starch biodegradable film has the best condition at 50°C to 60°C at approximately 5.5 hours. Elongation optimum conditions shows contrast value of temperature and time. Meanwhile, for Wendy (2020) study, it shows the best percentage loading of cassava-peel starch is at 20% to achieve high stress and strain at break. The optimised mechanical properties via Taguchi and RSM are rather different and hence validation on mechanical properties at above mentioned conditions need to be performed experimentally.

On Steel Surface Modification via Embedment of ZnNPs@polystyrene Composite as Anti-corrosive Template

Corrosion is one of the serious problems countered in different industries as it dramatically causes strong impacting on the infrastructures. As an attempt for sorting out such problem, this approach investigated an innovative strategy for synthesis of corrosion inhibitor for steel surfaces based on composite of polystyrene and zinc nanoparticles (ZnNPs@polystyrene composite). The successive immobilization of ZnNPs (size average of 4-50 nm) within polystyrene matrix (Mwt of 372.587 g/ mole and degree of polymerization equals 3582 repeat unit/ molecule) for clustering of the desirable ZnNPs@polystyrene composite (surface area of 33.62 m2/g, average pore diameter of 9 nm) was approved via several instrumental analyses of FT-IR, XRD, SEM, HRSEM, EDX, TEM and BET with estimation of total pore volume and average pore diameter for the prepared composite. Thermal stability of the prepared composite was affirmed via TGA analysis. Corrosion percentage via weight loss percent in three media of water, H2SO4 and diesel fuel was estimated to reach maximally to 25 % in case of H2SO4, while, corrosion inhibition efficiency (CIE) percentage estimated according to weight loss to reach 94.27, 88.18 and 85.05 % after 10 days of soaking the steel samples coated with the synthesized ZnNPs@polystyrene composite (800 ppm) at 25 ℃, while, elevation of temperature up to 45 ℃, resulted in non-significant effect on the estimated CIE to be diminished to 91.8, 85.2 and 81.1% after soaking in water, diesel fuel and sulfuric acid as corrosion media, respectively. CIE was estimated to be near 30% in case of coating steel samples with polystyrene polymer, to be significantly increased to near 80 % and formidably jumped to near 100% by coating with ZnNPs@polystyrene composite, with weight percent of 30 & 50% of ZnNPs, respectively. In addition to, Zeta potential was also detected to be - 9.67 in case of untreated steel samples, while, it became - 4.98 after coating of sample with ZnNPs@polystyrene composite. Eventually, from Arrhenius plots, activation energies and thermodynamic parameters of rate constant, enthalpy (ΔH) and entropy (ΔS) confirmed that the interaction is more taking place between the corrosion species and ZnNPs@polystyrene composite as corrosion inhibitor rather than with steel surface. Postulation of the reaction mechanism for the anticorrosive action of the synthesized ZnNPs@polystyrene composite was presented according to the illustrated instrumental analyses.