Use of carbon-encapsulated zero-valent iron nanoparticles from waste biomass to hydrogen sulphide wet removal.

This study evaluates the use of carbon-encapsulated zero-valent iron nanoparticles for biogas upgrading in wet systems. The nanoparticles were produced by hydrothermal carbonization, using olive mill waste (OMW) or microalgae as carbon sources. The solids were characterized to investigate the specific surface area, total and zero-valent iron content, pH and chemical and crystalline composition.

Thermal Decomposition of Bio-Based Plastic Materials.

This research delves into a detailed exploration of the thermal decomposition behavior of bio-based polymers, specifically thermoplastic starch (TPS) and polylactic acid (PLA), under varying heating rates in a nitrogen atmosphere. This study employs thermogravimetry (TG) to investigate, providing comprehensive insights into the thermal stability of these eco-friendly polymers. In particular, the TPS kinetic model is examined, encompassing the decomposition of three distinct fractions.

Mini-review: Nanoparticles for enhanced biogas upgrading.

This mini-review is intended to explore the innovative applications of nanoparticles (NPs) in biogas upgrading, emphasizing their capacity to enhance biogas quality. Numerous studies underscore how NPs, when applied during anaerobic digestion, can boost not only the quantity but also the quality of the produced biogas, leading to reduce significantly the concentration of hydrogen sulphide or even to remove it completely. Moreover, NPs are proving to be excellent alternatives as adsorbent materials, achieving up to 400 mg g NPs.

Evaluation of thermal drying for the recycling of flexible plastics.

The drying of flexible plastic waste is a current industrial problem in the plastic recycling sector. The thermal drying of plastic flakes is considered the most expensive and the most energy-consuming step in the recycling chain, which represents an environmental issue. This process is already present on the industrial scale but not well described in the literature.

Heavy metals, PAHs and POPs in recycled polyethylene samples of agricultural, post-commercial, post-industrial and post-consumer origin.

In the present work, recycled polyethylene (LDPE) samples of agricultural, post-commercial, post-industrial and post-consumer origin were selected and analysed. The analysis comprised the determination of different contaminants such as metals, polycyclic aromatic hydrocarbons (PAHs), dioxin-like biphenyl polychlorides (PCBs), and polychlorinated-dibenzo-p-dioxins and furans (PCDD/Fs). A comparison with one sample of virgin plastic (unrecycled) was performed.

Presence of microplastics in commercial canned tuna.

The present study aims to determine the presence of synthetic polymeric microparticles (MPs) in samples of canned tuna. An analysis procedure of these microparticles was developed and tested. Four brands of tuna marketed in Ecuador canned both in water and oil were analysed.

Role of Gallic Acid in the Synthesis of Carbon-Encapsulated Iron Nanoparticles by Hydrothermal Carbonization: Selecting Iron Oxide Composition.

In this work, the role of phenolic compounds in the hydrothermal synthesis of carbon-encapsulated iron nanoparticles (CEINs) was studied. To model phenolic compounds, gallic acid (GA) was selected, with glucose as the carbon source. Iron was found as α-FeO, γ-FeO, FeO, and zero-valent iron (ZVI) depending on the synthesis pH and GA/Fe molar ratio.

Heterogeneous Fenton Degradation of Patulin in Apple Juice Using Carbon-Encapsulated Nano Zero-Valent Iron (CE-nZVI).

Patulin (PAT), a mycotoxin found mainly in matured apples, is produced by different species of fungi, mainly and is found in various fruits and vegetables used to produce juice. Little focus has been placed on nano-technological methods for the mitigation of this problem. In this work, carbon-encapsulated nano-zero valent iron (CE-nZVI) particles were synthesized and used as heterogeneous Fenton agents for the degradation of PAT in apple juice.

Odorant composition of post-consumer LDPE bags originating from different collection systems.

The establishment of recycling systems aiming at high-quality recyclates from post-consumer plastic waste are essential to avoid the waste of resources. One main impediment for introducing recyclates into the market is their unwanted odor. For this reason, this study aimed at determining if the collection strategy affects the odor profile of post-consumer LDPE bags.

Recyclability of four types of plastics exposed to UV irradiation in a marine environment.

Plastics are the most abundant products in the world and therefore also represent the largest volume of materials found in the sea. Their resistance to degradation makes them dangerous for the marine environment. In this study, the degradation of the four main plastics (Nylon, Polyethylene (PE), Polypropylene (PP), Polyethylene terephthalate (PET)) found in the sea was observed for 6.

Author Correction: Microplastics in Spanish Table Salt.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Microplastics in Spanish Table Salt.

Marine debris is widely recognized as a global environmental problem. One of its main components, microplastics, has been found in several sea salt samples from different countries, indicating that sea products are irremediably contaminated by microplastics. Previous studies show very confusing results, reporting amounts of microparticles (MPs) in salt ranging from zero to 680 MPs/kg, with no mention of the possible causes of such differences.

Study of the presence of PCDDs/PCDFs on zero-valent iron nanoparticles.

Studies show that nanoscale zero-valent iron (nZVI) particles enhance the formation of chlorinated compounds such as polychlorinated dioxins and furans (PCDD/Fs) during thermal processes. However, it is unclear whether nZVI acts as a catalyst for the formation of these compounds or contains impurities, such as PCDD/Fs, within its structure. We analyzed the presence of PCDD/Fs in nZVI particles synthesized through various production methods to elucidate this uncertainty.

Predicting the drying properties of sludge based on hydrothermal treatment under subcritical conditions.

The effects of hydrothermal treatment on the drying properties of sludge were determined. Sludge was hydrothermally treated at 180-260 °C for 0.5-5 h using NaOH and HCl as additives to influence reaction conditions.

Hydrothermal carbonization of industrial mixed sludge from a pulp and paper mill.

Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180-260°C for 0.5-5h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components.

Heavy metal release due to aging effect during zero valent iron nanoparticles remediation.

Zero valent iron nanoparticles (nZVI) represent a promising agent for environmental remediation. Nevertheless, their application presents some limitations regarding their rapid oxidation and aggregation in the media. The aim of this study was to determine the effect that nZVI aging has in heavy metal remediation in water.

Viability study of automobile shredder residue as fuel.

Car Fluff samples collected from a shredding plant in Italy were classified based on particle size, and three different size fractions were obtained in this way. A comparison between these size fractions and the original light fluff was made from two different points of view: (i) the properties of each size fraction as a fuel were evaluated and (ii) the pollutants evolved when each size fraction was subjected to combustion were studied. The aim was to establish which size fraction would be the most suitable for the purposes of energy recovery.

Low temperature thermal degradation of PCDD/Fs in soil using nanosized particles of zerovalent iron and CaO.

This study investigated the degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in contaminated soil using low temperature treatment (200-280°C) both alone and in combination with nanosized zerovalent iron (nZVI) particles or CaO. Control soil samples and soil fortified with nZVI particles or CaO were treated at 200 and 250°C in sealed glass ampoules. Treatment of the ampouled samples at 250°C was more effective than treatment at 200°C and the reduction in PCDD/F concentration was greatest when soil was treated at 250°C with nZVI addition (indeed, treatment at 200°C in the absence of nZVI resulted in increases in total PCDD and PCDD/F concentrations).

Formation of polychlorinated compounds in the combustion of PVC with iron nanoparticles.

The influence of iron nanoparticles in the fuel-rich combustion of PVC has been studied in this work. Dynamic runs for PVC and the mixture PVC and iron nanoparticles were firstly carried out by TGA-MS in order to study the influence of iron on the compounds evolved in the thermal degradation of PVC. To complete the study both PVC and a mixture of PVC and iron nanoparticles were burnt in a laboratory reactor under two different operating conditions: at 850 degrees C and in two stages, the first one at 375 degrees C and the resulting char cooled and subsequently burnt at 850 degrees C.

Decomposition of paper wastes in presence of ceramics and cement raw material.

Paper recycling is an environmental important activity that is carried out in all the countries, but during the recycling process a paper waste is produced. Generally these wastes are placed in landfill sites but it is possible to profit it as secondary fuel and raw material in manufacture furnaces. In this work the combustion of the waste papers with cement and ceramic raw material has been studied with the objective to analyse the interaction of these substances with the emitted pollutants like PAHs and PCDD/Fs.

Remediation of PCB contaminated soils using iron nano-particles.

In this study, iron nano-particles were used to remediate PCB contaminated soil and an attempt was made to maximize PCB destruction in each treatment step. The results show that nano-particles do aid in the dechlorination process and high PCB destruction efficiencies can be achieved. The destruction efficiency during the preliminary treatment (mixing of soil and iron nano-particles in water) can be increased by increasing the water temperature.

Dioxin production during the thermal treatment of meat and bone meal residues.

Safe animal by-product disposal is a priority target as a result of the Bovine Spongiform Encephalopathy crisis in the European beef industry. One such disposal option is the incineration of by-product material such as meat and bone meal residues (MBM) for the purpose of energy recovery. Although currently applied, the thermal decomposition of MBM wastes has not been scientifically studied until now.

Semivolatile and volatile compounds in combustion of polyethylene.

The evolution of semivolatile and volatile compounds in the combustion of polyethylene (PE) was studied at different operating conditions in a horizontal quartz reactor. Four combustion runs at 500 and 850 degrees C with two different sample mass/air flow ratios and two pyrolytic runs at the same temperatures were carried out. Thermal behavior of different compounds was analyzed and the data obtained were compared with those of literature.

Comparison of volatile aldehydes present in the cooking fumes of extra virgin olive, olive, and canola oils.

Emissions of low molecular weight aldehydes (LMWAs) from deep-frying of extra virgin olive oil, olive oil, and canola oil (control) were investigated at two temperatures, 180 and 240 degrees C, for 15 and 7 h, respectively. The oil fumes were collected in Tedlar bags and then analyzed by gas chromatography-mass spectrometry. Seven alkanals (C2-C7 and C9), eight 2-alkenals (C3-C10), and 2,4-heptadienal were found in the fumes of all three cooking oils.