Polyethylene Terephthalate Bottles Research Articles

Sulfonated cobalt phthalocyanine/NH2-MIL-125 heterojunction modified electrospun nanofiber membrane for emulsion separation and PMS-photocatalysis synergistic degradation

Membrane technology for wastewater remediation has generated significant interest, however, the single functionality, dull wettability and easy fouling property of the membrane hinder its practical application. Herein, a self-cleaning and multi-use superwetting nanofiber membrane was prepared by electrospinning and subsequent spraying technique. The sulfonated cobalt phthalocyanine/NH2-MIL-125 (CoPcS/NMIL) heterojunction was uniformly enrobed over polyethylene terephthalate (PET) electrospun membrane derived from waste PET bottles. The unique CoPcS/NMIL heterojunction exhibited a dual driving effect in photocatalytic activity and membrane wettability. Therefore, the fabricated CoPcS/NMIL@PET composite membrane demonstrated its capability to address complex water pollution issues effectively. The composite membrane exhibited notable flux permeation ability (538–3180 L m−2 h−1) and achieved excellent separation efficiency of over 99 % for diverse oil-in-water emulsions under the gravity filtration condition. Notably, the membrane can efficiently deal with stubborn high-viscosity crude oil fouling profiting from the photocatalytic self-cleaning function. A high flux recovery ratio of 93.6 % and a low irreversible fouling resistance ratio of 6.4 % can be obtained after 30 min of visible light irradiation. Impressively, CoPcS/NMIL@PET membrane exhibited enhanced permeation flux, separation efficiency and self-cleaning capacity compared to NMIL@PET membrane. Meanwhile, the CoPcS/NMIL@PET-activated peroxomonosulfate (PMS) system exhibited extremely high degradation performance for RhB under visible light with the degradation efficiency of 98 % within 10 min, suggesting its potential in the rapid purification of water-soluble organic pollutants. In addition, the CoPcS/NMIL@PET membrane has good chemical stability and mechanical properties for potential long-term use. Moreover, the demulsification mechanism in oil-water separation and PMS-photocatalysis synergetic mechanism over the fabricated CoPcS/NMIL@PET membrane were also investigated in detail. The research offers a promising approach for the design and fabrication of novel nanofiber membranes that incorporate photosensitizers and MOFs functional surfaces to address the challenges associated with such wastewater treatment.

Development of predictive model for compressive strength of eco-brick masonry walls using numerical method

The usage of waste plastics in the form of eco-bricks for the construction of buildings is gradually gaining traction. However, the performance of eco-brick masonry walls is not sufficiently known, and the process of setting up experimental rigs for the conduct of compressive strength test of masonry are usually cumbersome and expensive. This study investigated the compressive strength performance of eco-brick masonry walls and developed a predictive model for evaluating the strength of eco-brick masonry walls. Waste polyethylene terephthalate (PET) bottles were physically recycled and utilised to manufacture four samples of eco-bricks, strength grades 40.5, 21.02, 13.52 and 3.05 N/mm2 using stone dust, sharp sand and laterite at predetermined moisture contents. The eco-bricks were laid with seven grades of mortar to build 54 eco-brick masonry prisms. A quasi-static compressive loading test was carried out on the masonries, and predictive models were developed using multiple non-linear regression. The study found that eco-brick masonry prisms supported large loads and failed due to the propagation of tensile cracks and debonding of the units. The study also found that the compressive strength of eco-brick masonry is a power function of the compressive strength of eco-bricks and the mortar used for the bonding. It was determined that the mean ratio of the expected to experimental prism strength was 1.002. The mathematical model developed in this study for predicting the strength of eco-brick masonries can significantly evaluate the compressive strength of eco-brick masonry.

A New Sustainable PPT Coating Based on Recycled PET to Improve the Durability of Hydraulic Concrete.

A new, sustainable polypropylene terephthalate (PPT) coating was synthesized from recycled polyethylene terephthalate (PET) and applied onto a hydraulic concrete substrate to improve its durability. For the first step, PET bottle wastes were ground and depolymerized by glycolysis using propylene glycol (PG) in a vessel-type reactor (20-180 °C) to synthesize bis(2-hydroxypropyl)-terephthalate (BHPT), which was applied as a coating to one to three layers of hydraulic concrete substrate using the brushing technique and polymerized (150 °C for 15 h) to obtain PPT. PET, BHPT, and PPT were characterized by FT-IR, PET, and PPT using TGA, and the PPT coatings by SEM (thickness), ASTM-D3359-17 (adhesion), and water contact angle (wettability). The durability of hydraulic concrete coated with PPT was studied using resist chloride ion penetration (ASTM-C1202-17), carbonation depth at 28 days (RILEM-CPC-18), and the absorption water ratio (ASTM-C1585-20). The results demonstrated that the BHPT and PPT were synthetized (FT-IR), and PPT had a similar thermal behavior to PET (TGA); the PPT coatings had good adhesion to the substrate, with thicknesses of micrometric units. PPT coatings presented hydrophilic hydrophilic behavior like PET coatings, and the durability of hydraulic concrete coated with PPT (2-3 layers) improved (migration of chloride ions decreased, carbonation depth was negligible, and the absorption water ratio decreased).

A waste-to-wealth conversion of plastic bottles into effective carbon-based adsorbents for removal of tetracycline antibiotic from water

Currently, plastic waste and antibiotic wastewater are two of the most critical environmental problems, calling for urgent measures to take. A waste-to-wealth strategy for the conversion of polyethylene terephthalate (PET) plastic bottles into value-added materials such as carbon composite is highly recommended to clean wastewater contaminated by antibiotics. Inspired by this idea, we develop a novel PET-AC-ZFO composite by incorporating PET plastic-derived KOH-activated carbon (AC) with ZnFe2O4 (ZFO) particles for adsorptive removal of tetracycline (TTC). PET-derived carbon (PET-C), KOH-activated PET-derived carbon (PET-AC), and PET-AC-ZFO were characterized using physicochemical analyses. Central composite design (CCD) was used to obtain a quadratic model by TTC concentration (K), adsorbent dosage (L), and pH (M). PET-AC-ZFO possessed micropores (d ≈ 2 nm) and exceptionally high surface area of 1,110 m2 g–1. Nearly 90% TTC could be removed by PET-AC-ZFO composite. Bangham kinetic and Langmuir isotherm were two most fitted models. Theoretical maximum TTC adsorption capacity was 45.1 mg g–1. This study suggested the role of hydrogen bonds, pore-filling interactions, and π-π interactions as the main interactions of the adsorption process. Thus, a strategy for conversion of PET bottles into PET-AC-ZFO can contribute to both plastic recycling and antibiotic wastewater mitigation.

Multi-criteria decision making tool for sustainable concrete production using waste polyethylene terephthalate bottle cap aggregates

The widespread use of concrete has raised concerns about the consumption of its raw materials. To address this issue, researchers are actively exploring alternative waste materials to reduce the environmental impact of the construction industry. With this objective current study aims to investigate potential use of waste polyethylene terephthalate (PET) bottle cap aggregates on the characteristics of concrete, both in its fresh and hardened states. Three variations of modified waste PET aggregates (PETA): full (F), half (H), and quarter (Q), with the aim of evaluating their suitability as replacements for conventional coarse aggregates (CCA) was examined. The research assesses the effects of different PETA proportions (3%, 5%, and 8%) on concrete workability, compressive strength, splitting tensile strength, and flexural strength. The findings reveal that PETA-F and PETA-H adversely affect workability, primarily due to their larger surface area and difficulty in achieving homogeneous blending with other ingredients. In contrast, PETA-Q exhibits superior workability. The use of PETA-Q results in reduced compressive strength due to its smaller size and limited load-bearing capacity. Notably, PETA-H demonstrates improved compressive strength after 28 days. Interestingly, PETA-Q shows enhancements in splitting tensile and flexural strength, making it the top-performing alternative for fresh and hardened concrete properties. Overall, this research indicates that PETA-Q is most suitable for sustainable concrete production. Furthermore, the application of a multi-criteria decision-making tool validates our findings and determines that a 5% replacement of CCA with PETA is optimal, as higher replacements result in strength reduction. The utilization of PETA not only minimizes CCA consumption but also contributes to the development of eco-friendly, sustainable concrete. This study underscores the potential of environmentally conscious concrete and encourages the adoption of sustainable solutions for plastic waste management.

Spent Lithium-Ion Batteries Derived Co3O4 for Electrocatalytic Polyethylene Terephthalate Plastic Recycling.

Spent lithium-ion batteries (LIBs) are an essential secondary resource containing valuable metal elements. Transforming spent LIBs into efficient catalysts through a simple process presents a promising strategy to address both metal resource scarcity and clean energy challenges. Herein, a deep eutectic solvent-assisted synthesis of Co3O4 material from spent LIBs is proposed. The obtained Co3O4 material possesses efficient and stable electrocatalytic activity for converting raw polyethylene terephthalate (PET) bottles into high-purity formic acid and terephthalic acid products under ambient conditions. As expected, the Co3O4 catalyst exhibits a high FE of 92 % with a concentration of produced potassium formate of 23.6 mM under alkaline conditions. This study presents a waste-treating-waste strategy for the simultaneous recovery of spent LIBs and PET waste in a greener manner.

Persistence of A-234 nerve agent on indoor surfaces

Understanding the fundamental physical characteristics of extremely toxic compounds and their behavior across different environments plays a crucial role in assessing their danger. Additionally, this knowledge informs the development of protocols for gathering forensic evidence related to harmful chemicals misuse. In 2018, former Russian spy Sergei Skripal and his daughter were poisoned in Salisbury, England, with a substance later identified as the unconventional nerve agent A-234. Contamination with the compound was found on items inside Skripal's home. The aim of this paper was to determine the persistence of A-234 on selected indoor surfaces. Ceramics, aluminum can, laminated chipboard, polyvinyl chloride (PVC) floor tile, polyethylene terephthalate (PET) bottle, acrylic paint and computer keyboard were used as matrices. The decrease in surface contamination and further fate of the compound was monitored for 12 weeks. Persistence determination involved optimizing the wipe sampling method. Simultaneously, evaporation from the surface and permeation of the contaminant into the matrix were closely monitored. The experimental findings indicate that the nerve agent exhibits remarkable persistence, particularly on impermeable surfaces. Notably, the process of A-234 evaporation plays a minor role in determining its fate, with detectable concentrations observed solely above solid, non-porous surfaces such as ceramics and aluminum can. The surface persistence half-life varied significantly, ranging from 12 min to 478 days, depending on the material. The article has implications for emergency response protocols, decontamination strategies, public health and crime scene investigations.

Abolishing Single-Use Plastic Water Bottles in Dubai Hotels as a Voluntary Act—Scenarios and Environmental Impacts

Dubai, a popular vacation spot, has launched an initiative to reduce reliance on single-use plastic water bottles. Tourists in Dubai widely utilize PET (Polyethylene Terephthalate) water bottles, and significant quantities of greenhouse gases (GHG) are released during the production and disposal of PET bottles. In response to Dubai’s initiative, some hotels eliminated PET bottles and substituted them with environmentally favorable alternatives. These hotels are considered adopters of the initiative, while other hotels that might follow are imitators. Thus, innovation diffusion theory (IDT) is used in this work to forecast the transition of hotels to non-PET bottles. The diffusion of this new behavior is simulated using a system dynamic (SD) model, where factors pushing imitators to abolish PET bottles are found using the Delphi method and hotel surveying. Moreover, the importance of each identified factor is found using an analytical hierarchical process (AHP). Since hotels are divided into several categories based on their service quality, the analysis shows that hotels are affected by other hotels in their category or better categories. Using this conceptual understanding, Bass and generalized Bass modeling are used in the SD model to study how imitating hotels will follow the adopters. Best-, average-, and worst-case scenarios are studied to help decision-makers understand what to expect in the future. For the best- and average-case scenarios, the SD simulation shows that all hotels will potentially have abolished PET bottles in 25 years. However, only 16% of hotels will have cancelled PET bottles in 25 years if the worst-case scenario occurs; thus, decision-makers need to intervene to expedite the process.

Cowpea storage: Can small farmers use polyethylene terephthalate bottles and wood ash as an alternative to avoid damage caused by Callosobruchus maculatus?

The aim of this study was to investigate the effectiveness of the combination of Polyethylene terephthalate (PET) bottles and ash in controlling Csllosobruchus maculatus and maintaining the quality of grains of cowpea cultivars. The following storage structures were used: PET bottle in airtight conditions and glass jars in non-airtight condition (control). The wood ash used in this research came from the burning process of eucalyptus (Eucalyptus grandis) wood. The experiment was carried out in a 2 × 2 × 4 factorial scheme, with two cowpea cultivars (BRS Tumucumaque and BRS Guariba), two forms of storage (PET bottle – airtight and glass jars – non-airtight) and four doses of eucalyptus wood ash (0.0; 1.0; 2.0 and 4.0 kg t−1), in a completely randomized design with three replications. Each plot contained 500 g of cowpea. The effectiveness of treatments was measured by the instantaneous population growth rate (ri) of C. maculatus. In ri, 35 adult, non-sexed insects were used. Adult progenies were counted after 60 days of storage. For qualitative grain evaluation the following characteristics were analyzed: water content, germination, apparent specific mass and electrical conductivity. The results obtained in this study confirm for the first time that the combined use of PET and ash do not affect grain quality and it is efficient in the management of C. maculatus in cowpea cultivars. In the present study, a significant reduction in the emergence of C. maculatus was observed in the BRS Tumucumaque, making it possible that this cultivar has some potential for resistance to bruchid.

Synthesis of Cr(OH)3/ZrO2@Co-based metal-organic framework from waste poly(ethylene terephthalate) for hydrogen production via formic acid dehydrogenation at low temperature

Recycling waste polyethylene terephthalate (PET) bottles into value-added ligand materials for synthesizing metal-organic frameworks (MOFs) derived catalysts is an eco-friendly and economically viable process. The waste PET bottles were readily broken down into 1,4-benzenedicarboxylic acid (BDC) ligands in a highly alkaline environment. Herein, we fabricated a Co@Cr(OH)3/ZrO2 catalyst via the carbonization of PET-derived UiO-66 metal-organic frameworks for the catalytic dehydrogenation of formic acid at low temperatures. The as-prepared Co@Cr(OH)3/ZrO2 catalyst provides a turnover frequency of 7685 h−1 for hydrogen generation (120 mL in 1.5 min) at ambient temperature. This is due to the uniform dispersion of the fine metal nanoparticle (NPs) (Co NPs, ∼3.75 nm) and the synergistic effect of the Co NPs and Cr(OH)3/ZrO2 supports. In addition, the characterization results indicate that porous Zr-MOFs may effectively enclose tiny particles, which is favorable for enhanced dehydrogenation performance. In addition, the Co@Cr(OH)3/ZrO2 catalysts demonstrated excellent stability against aggregation and were recyclable over seven cycles without any significant catalytic loss. Thus, this study provides a sustainable methodology for the development of MOF-derived, effective, and stable catalysts for formic acid dehydrogenation towards hydrogen production.

Vendor Managed Inventory (VMI) Implementation in Recycled PET Preform for The Beverage Industry

The beverage industry is a company that is focused on producing mineral water in Polyethylene Terephthalate (PET) bottles. PET bottles serve as the primary packaging choice in the beverage industry, making the use of preforms as a material for bottles unavoidable. On the other hand, the public is more aware of using sustainable materials. Adapting market awareness, the company shifted from virgin material to recycled material. Due to the significant initial investment, the company has decided on a single supplier strategy for recycled PET preform suppliers. This policy forces the company to manage the supplier to meet the company’s delivery accomplishment target. Currently, in the management of beverage found in the industry, the supplier only reaches 50% of delivery accomplishments, whereas the company target is 90%. The beverage industry strived for a revolution, so the company’s target was achieved. The vendor managed inventory method is implemented in this study to create a new revolution for PET preform suppliers, a new replenishment system. After the implementation of Vendor Managed Inventory (VMI), there has been an improvement, reaching 95% in delivery accomplishment. The adoption of vendor managed inventory ensures the attainment of the company’s objectives.

Daily Use Water Bottles as a Hub for Microbial Population: A Comparative Study of PET vs. Stainless Steel Water Bottles and Outcome of Washing Strategy Intervention

ABSTRACT Water bottles for everyday usage are a typical addition to people’s life and offer a practical way to stay hydrated. Even though safe and clean water is preferred for consumption, the water bottle or container used to drink water was never considered to be cleaned. Here, we examined the adhering microbial populations in water bottles composed of stainless steel (SS) and polyethylene terephthalate (PET). A total of 30 water bottles—15 PET and 15 SS—were gathered from different users. To identify and quantify the adhering microbial populations, microbial swabs from the inside surface of the bottles were collected and later cultivated on certain growth media. Overall the microbial load of PET is significantly higher than the SS water bottles of 68.8 + 19.1 cfu/ml and 35.4 + 8 cfu/ml respectively at initial sampling (P = 0.0027). We also evaluated the efficiency of various cleaning procedures in eliminating adherent bacteria populations. The cleaning strategy significantly reduced the microbial load (P<0.0001). The mean load observed was 11.2 + 2.3 cfu/ml post-wash. This comparison study offers important new information about the adherent microbial populations found in SS and PET water bottles used every day, in the end. This finding emphasizes the necessity of routine cleaning and upkeep of these bottles to reduce the possibility of microbial contamination and the accompanying health risks.

Stiffness and Strength of an Artificially Cemented Waste-PET-Shred Reinforced Clay

AbstractThis study explores whether the polyethylene terephthalate bottle shreds (PETBS), could be a viable alternative additive in order to reduce the usage of traditional cement in geotechnical and transportation projects. Through a comprehensive study, clayey soil was stabilized with varying quantities (0.1–1% of solid mass) of PETBS of two different size ranges. Optimal dosages were chosen, followed by additional tests incorporating small amounts of (5, 7 and 10% of solid mass) cement enhancement. After curing periods of 7 and 28 days, California bearing ratio (CBR) tests and ultrasonic pulse velocity (UPV) test results revealed that the addition of PETBS enhanced CBR values and initial shear modulus (G0) in both plain and cement treated samples. Scanning electron microscope (SEM) images also affirmed the improvement of strength at the microstructural level. Notably, PETBS of size 2–4.75 mm exhibited superior performance compared to size 0.42–0.841 mm, with an optimal content range of 0.6–0.8%. It was observed that the addition of PETBS to artificially cemented soil improved CBR values by up to 35%, while also modifying stiffness and brittleness, rendering the soil more ductile. Ultimately, a regression model was proposed to facilitate estimates of CBR and G0 in PETBS-reinforced cemented clay, to accommodate varying PETBS grading and content. The suggested approach promotes cost-effective and eco-friendly solutions by reducing pavement thickness and enhancing soil stability, demonstrating the potential of repurposing PET waste as a sustainable strategy in various engineering projects.

Non-contact terahertz evaluation of the melting point for PET bottles

From measurements of the terahertz spectra of commercial polyethylene terephthalate (PET) bottles, a linear correlation is observed between the melting point of the plastic and the absorption intensity around 4 THz. This result indicates that the melting point could be estimated using a non-contact method from the 4 THz peak intensity of the PET bottles. The melting points of the PET bottles used as samples in this study varied from 500 to 503 K. In the present-day recycling process, all waste PET is heated to the same temperature above the highest of the melting points. Based on the data obtained in this study, if could be possible to sense the melting point of waste PET in advance without heating and therefore to optimize the thermal budget of the recycling process.

Waste polyethylene terephthalate plastic derived Zn-MOF for high performance supercapacitor application

A simple chemical approach was used to prepare Zn-MOF or MOF-5 derived from polyethylene terephthalate bottles for supercapacitor applications. The morphology, and structure of PET-derived MOFs were characterized using various techniques, including scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, fourier transform infrared spectroscopy, and BET surface area and nitrogen adsorption/desorption analysis. The BET surface area of MOF-5 was determined to be 88 m2g−1 and N2 adsorption–desorption analysis, showed the type-IV isotherms and suggest the existence of capillary condensation within the meso- and micropore structures. An excellent specific capacitance ranging from 341 to 191 F g−1 recorded form the scan rate of 2–200 mV s−1 by CV for Zn-MOF. Moreover, the highest specific capacitance 353 F g−1 calculated at 0.5 A/g current density. The highest value of specific capacitance Cs 353 F g−1 was found for lowest current density of 0.5 A/g. An excellent cyclic stability was obtained after running 2000 cyclic runs at a scan rate of 50 mV s−1. The small semicircle of EIS plot exhibits superior electrochemical performance of the Zn-MOF. The waste PET plastic derived Zn-MOF showed an excellent supercapacitor performance which can be utilized in energy storage applications. This approach not only facilitates environmental remediation but also offers a valuable organic linker for energy material synthesis.

AspenPlus-based techno-economic analysis of solar-assisted sorption-enhanced gasification for hydrogen and chemicals recovery from polyethylene terephthalate waste

Although the recycling of polyethylene terephthalate (PET) bottles is well-operating in several countries, less than 10% of PET plastic waste was recycled in a closed loop globally, and the rest was discarded as leakage. A process to recover hydrogen and valuable chemicals through solar-assisted PET sorption-enhanced gasification was analyzed. PET steam gasification with CaO and solar-assisted calcium looping processes were already experimentally studied in our previous work to obtain optimized processing conditions. In this paper, the integrated process with product purification, steam power plant, and LiBr-H2O absorption chiller was simulated with Aspen Plus based on previous experimental results to investigate the techno-economic performance. Material flows, energy balance, exergy destruction, and economics were analyzed. Day and night mode operations at different seasons were evaluated based on energy balance and the weather conditions of Naples, Italy. The energy and exergy efficiencies of day and night modes varied between 62%–72%. The annual production yields of hydrogen and benzene were 684 t and 6286 t, respectively. Due to the high production of benzene, its higher price (>1092 €/t) would make the project feasible with a larger than 12% internal rate of return value and competitive break-even hydrogen price (less than 4 €/kg). The results show that this integrated process could be technically and economically feasible. It has the potential to be implemented for hydrogen and benzene recovery from PET plastic waste with sustainable solar heat source and zero fossil CO2 emissions.

Levels of Phthalate Acid Esters in Carbonated Soft Drinks Bottled in Polyethylene Terephthalate (PET) Bottles Kept under Various Storage Conditions in Mwanza City, Tanzania

Background: Carbonated soft drinks (CSD), packaged in PET (polyethylene terephthalate) bottles, are among the most widely consumed non-alcoholic beverage globally. People of all ages enjoy CSDs for their flavour, mouthfeel, crispness, freshness, and capacity to both quench thirst and provide mental refreshment. Terephthalic acid, ethylene glycol, and other additives such as phthalates are the materials used to make these PET bottles. Several studies have demonstrated that phthalates may migrate into packaged goods and, when consumed, can cause several ill-health conditions to humans. Type II diabetes, obesity, asthma, male and female reproductive disorders, tumours (including breast cancer), pituitary, hypothalamic, and peripheral hormone disorders, behavioral issues, and neurodevelopmental disorders are among the health issues reported to be associated with phthalates. Objective: This study aimed to ascertain the presence and concentration of phthalates in PET bottled carbonated soft drinks produced in Mwanza City, and to examine the effects of various storage conditions on the migration of these contaminants into the product. Methods: Liquid-liquid extraction, clean-up techniques, and chromatographic analysis were used as the methods of determination to identify and quantify the specific phthalates compounds. Results: The findings demonstrated that after being stored outdoors for four to six months, the migration, especially for dibutyl phthalate (DBP) and di [2-ethylhexyl] phthalate (DEHP), became more apparent. After two, four, and six months of indoor storage, there was no appreciable change in the mean concentrations of DMP (dimethyl phthalate), DEP (diethyl phthalate), DBP (dibutyl phthalate), and DEHP for either brand in this study. Compared to indoor storage, the DBP and DEHP migration increased by up to 24-fold when the two brands were kept outdoors for four and six months. Thus, the safety and quality of carbonated soft drinks were seriously compromised by the phthalate compounds from the PET bottles that these companies were using. Conclusion: The study's conclusions show that PET packaging, which is influenced by the bottle manufacturing process and raw material formulations for packages of the studied CSDs, are responsible for the migration of phthalates into the products. The storage conditions and time are established to be the primary causes of phthalates migration in bottled carbonated soft drinks. Though the migration figures in this study are lower than those of the other studies from different locations that were compared, it is important to remember that these compounds may interfere with hormones even in small quantities.

Understanding the sources of marine litter in remote islands: The Galapagos islands as a case study

Determining the sources of marine litter is necessary to mitigate this increasing global problem. Plastic bottles are useful tracers of marine litter and constitute the main item (24%) stranding on remote beaches in the Galapagos Islands. The aim of this study was to estimate the abundance of plastic bottles in remote beaches and inferred their sources. To do so, we collected plastic bottles at 60 remote Galapagos Island beaches from 2018 to 2022. 76% of beaches were qualified as badly polluted, with >34 bottles·100 m−1. Most identified bottles came from Peru (71%), followed by China (17%) and Ecuador (9%). Although most locally-sold products are made in Ecuador, they contribute little to beach litter loads. Polyethylene terephthalate bottles with lid (necessary for litter dispersal) represented 88% of all bottles, demonstrating that most of the litter reaching the Galapagos comes from distant sources, mainly from South America. However, bottle ages indicate that at least 10% of Peruvian, 26% of Ecuadorian, and all Chinese bottles likely were dumped from ships. Reducing marine litter reaching the Galapagos Islands requires tackling litter leakage from land-based sources in South America and better compliance with regulations banning the dumping of plastics and other persistent wastes from ships.

A statistical-experimental study to investigate the optimal parameters of fibres made from waste PET bottles for strengthening concrete

This research investigated using waste polyethylene terephthalate (PET) bottle fibres in concrete. Experimental tests were conducted to evaluate the mechanical properties of PET fibre-strengthened concrete. The effects of the fibre volume fraction and fibre length were studied to obtain optimal values. Moreover, a thorough statistical analysis was performed to identify the parameter that impacts the inclusion of PET fibres in concrete. Furthermore, the study explored the effect of PET fibres on reinforced concrete beams of shear failure mode. The results showed that incorporating PET fibres significantly enhances the ductility of the concrete material and reduces shrinkage. It also promotes the initial stiffness, the inelastic absorbed energy and the ductility of steel-reinforced concrete beams.

Evaluation of the Fertilizing Power of Sludge from Physicochemical Water Purification Stations: Case of the Yato Station, Littoral-Cameroon

The Yato physicochemical water purification station is located in the commune of Dibombari in the Littoral-Cameroon region. It is one of the largest drinking water production stations in the Central African sub-region. This work aims to evaluate the agronomic power of the sludge from this drinking water production station. To achieve this objective, mixed samples of sludge from sludge treatment basins (taken according to the technique described in GIDS-A003 point 6 as explained in the Solid and pasty waste sampling strategy of the Code of Good Practice No. 2). and primary settling basins (collected in transparent 1.5L polyethylene terephthalate bottles) were analyzed. Likewise, three soil samples (marsh, Point 1 and Point 2) were taken and then sent to the laboratory where physicochemical analyzes were carried out. The characteristics of the samples that were analyzed are: particle size, texture (sand, silt, clay) and physicochemistry (organic matter, CEC, sum of exchangeable bases, calcium, nitrogen, potassium and magnesium). The results obtained show that the soils exposed to contamination from the sludge of the station have better agronomic properties both on a physical level with a stable structure favorable to plant growth and good aeration unlike the soils far from the station which presented a high risk. degradation; that on the chemical level with an optimal cationic balance, a high reserve of exchangeable bases, a strong CEC but average limitations in assimilable phosphorus and pH unlike the soil far from the station which presented an insufficiency of potassium which did not facilitate a balance cationic, a low CEC but a pH above 5.5 which is the value recommended in agronomy. Biochemically, organic matter is above 2% in all soils, a mineralization rate less than 20 favoring the rapid mineralization of carbon and a release of nitrogen available to the plant. These results obtained allow us to conclude that the sludge from the Yato station can be used in agronomy as an organic fertilizer in order to correct the soil structure, the CEC, the cationic balances and also provide the soil with a good base reserve. However, treating this sludge with lime could regulate the pH of the soil and reduce the mobility of heavy metals in the soil.