A Preliminary Study on Recyclability of Mixed Plastic Wastes Recovered from Urban Collection

2021 ◽  
Vol 885 ◽  
pp. 109-114
Author(s):  
Raffaella Ferraioli ◽  
Loredana Incarnato ◽  
Luciano Di Maio ◽  
Paola Scarfato
Keyword(s):  
Water Content ◽  
Chemical Properties ◽  
Polymeric Materials ◽  
Melt Processing ◽  
Plastic Waste ◽  
Mechanical Recycling ◽  
Single Screw Extruder ◽  
Plastic Wastes ◽  
And Performance ◽  
Recycled Plastics

The management of post-consumer plastic waste (PCPW) is a real challenging issue due to difficulties in effectively identifying and sorting the collected plastics and in their mechanical recycling. Indeed, mechanically recycled post-consumer plastic waste usually shows poor performances compared to virgin materials, due to incompatibility between constituents, presence of degraded materials, hygroscopicity and bad odors. Compatibilizers and nanoparticles can help to improve recycled plastics quality, but to be chosen and dosed properly they require an in-depth knowledge and characterization of the raw waste. In this study, an analysis of polymeric materials obtained from the separation and mechanical recycling of post-consumer plastic wastes from urban collection as pellets (UPW) is reported. In particular, the experimental characterization was carried out in order to identify UPW composition, water content, physical-chemical properties and processability. It was found that UPW samples are mainly constituted of polyethylene (PE) and polypropylene (PP) in equal parts. UPW was submitted to a melt processing operation, using a lab-scale single-screw extruder, obtaining ribbons that were completely characterized. With the aim to investigate the effect of water content on the recycled material processability and performance, the recycling process was carried out both on undried and dried UPW pellets.

ESSENTIAL CHARACTERISTICS OF PLASTICS WASTE FOR PYROLYSIS PROCESS: COMPARISON OF SELECTED PACKAGING PLASTICS AND PVC

2015 ◽  
Vol 77 (23) ◽  
Author(s):  
Maryudi Maryudi ◽  
Martomo Setyawan ◽  
Noni Noni ◽  
Samihah Yahayor
Keyword(s):  
Water Content ◽  
Decomposition Temperature ◽  
Ash Content ◽  
Plastic Waste ◽  
Pyrolysis Process ◽  
Process Comparison ◽  
The Poor ◽  
Plastic Wastes ◽  
Three Stages ◽  
Plastics Waste

The poor degradability of plastics has led to huge plastics deposit in a landfill of which pyrolysis technology has been proposed to solve plastics waste problem. This paper reports the study on characteristics of two kinds of plastic wastes: selected packaging plastics and PVC. Characterizations have been performed for investigating water content, ash content, and decomposition temperature. The results revealed that the water content of packaging plastic waste was 0.69 ± 0.11%, while PVC was 1.22 ± 0.24%. The ash contents are 2.36 ± 1.03 % and 27.24±1.73 % for packaging plastics waste and PVC waste respectively. Plastic waste from packaging application and PVC waste decomposed at a temperature of 300-500°C and 200-800°C respectively. Decomposition of PVC waste took place in three stages: 200-370°C, 370-525°C and 600-800°C. It is recommended that the pyrolysis process should be conducted in the range of 300-500°C for packaging plastic waste and 200-800°C for PVC waste.

Cost analysis of plastic solid waste recycling in an urban district in Turkey

2019 ◽  
Vol 37 (9) ◽  
pp. 906-913 ◽  
Author(s):  
Ayten Genc ◽  
Ozgur Zeydan ◽  
Selin Sarac
Keyword(s):  
Solid Waste ◽  
Unit Cost ◽  
Operating Cost ◽  
Waste Recycling ◽  
Plastic Waste ◽  
Cost Evaluation ◽  
Mechanical Recycling ◽  
Urban District ◽  
Plastic Recycling ◽  
Plastic Wastes

The usage of plastics has exponentially increased in our daily lives over the past 50 years because of its durability, low costs and potential for diverse applications, such as widespread use as disposable items. In this study, first, the recycling cost of plastic wastes has been estimated by using actual data taken from a recycling centre, where plastic solid wastes were collected separately. The total amount of plastic wastes recycled at the centre was approximately 695 tonnes. The operating cost of plastics separation at the recycling centre, the transport of plastic wastes, labouring, maintenance, electricity, insurance and chemical costs were taken into consideration in the cost evaluation. Accordingly, the unit cost of recycling was calculated as US$0.40 kg−1 of plastic waste. This cost was compared with the predicted plastic recycling cost in the same region using statistical values. The predicted recycling cost was estimated based on assuming segregated collection by the municipalities of all PSW in municipal solid waste. Then the resulting unit cost of recycling was found to be US$0.25 kg−1 of plastic waste. In addition, the recycling costs were also evaluated including the revenue from the sales of recycled plastic granular. According to the evaluated total cost of plastic recycling, it can be concluded that mechanical recycling of plastics can only be an economical option if the recovery of plastics is improved.

APPLICATION OF COMBINED DATA-DRIVEN COMPUTATIONAL CHEMISTRY AND CHEMINFORMATICS APPROACHES TO PREDICT PROPERTIES OF MATERIALS

2021 ◽  
Author(s):  
Bakhtiyor Rasulev ◽  
Keyword(s):  
Biological Activity ◽  
Computational Chemistry ◽  
Materials Science ◽  
Structural Characteristics ◽  
Chemical Properties ◽  
Polymeric Materials ◽  
Data Driven ◽  
Ligand Docking ◽  
New Materials ◽  
And Performance

For the last two decades, breakthrough research has been going on in all aspects of materials science at accelerated pace. New materials of unprecedented functionality and performance are being developed and characterized. Moreover, the new materials with improved functionality are in high demand in the marketplace and this need increases in an exponential way for the new materials of desired functionality and performance. Here we show the application of combined computational and cheminformatics methods in various materials properties prediction, including organometallic materials, polymeric materials and nanomaterials. Since most of the materials are complex entities from a chemical point of view, the investigation of them requires an interdisciplinary approach, involving multiple aspects ranging from physics and chemistry to biology and informatics. In this report we show how the combination of computational chemistry, available experimental data, machine learning and cheminformatics approaches can help in materials research and properties assessment, such as physico-chemical properties, toxicity, and biological activity. We discuss here a few case studies where data-driven models developed to reveal the relationships between the physicochemical properties, biological activity and structural characteristics, by application quantum chemical, protein-ligand docking, cheminformatics approaches and developed nanodescriptors.

scholarly journals RECYCLING AND PYROLYSIS OF WASTE PLASTICS

2015 ◽  
Vol 3 (9SE) ◽  
pp. 1-3
Author(s):  
Amrita Khatri
Keyword(s):  
20Th Century ◽  
Science And Technology ◽  
Plastic Waste ◽  
Waste Plastics ◽  
Technological Solution ◽  
Plastic Pollution ◽  
Mount Everest ◽  
Mechanical Recycling ◽  
Vast Amount ◽  
Plastic Wastes

Plastic has achieved such an extensive market due to fact that it is lightweight, cheap, flexible and reusable. But now it is regarded as a serious hazard. All recommendation for and against plastics finally land up on the reality that plastics are slow to degrade. By the end of the 20th century, plastics are found as persistent polluters of many environmental niches, from Mount Everest to the bottom of the sea. There are numerous ways by which plastic pollution can be controlled.  Pyrolysis is referred to as polymer cracking and its main advantages are that it can deal with plastic waste .This paper provides an overview of the science and technology of pyrolysis of waste plastics. The major advantage of the pyrolysis technology is its ability to handle unsorted, unwashed plastic. The production of gasoline, kerosene and diesel from waste plastics is an emerging technological solution to the vast amount of plastics that cannot be economically recovered by conventional mechanical recycling. The disposal and decomposition of plastics has been an issue which has caused a number of research works to be carried out in this regard. Currently, the paper reviews the production of Petroleum-based fuel viz. gasoline, kerosene and diesel from recycling of waste plastics is an emerging technological solution to the vast amount of plastic wastes that cannot be economically recovered by conventional mechanical recycling operations. This involves the use of pyrolysis which permits recovery of valuable gasoline and diesel-range hydrocarbons from waste plastics that are otherwise land filled.

scholarly journals ANALYSIS OF PLASTIC WASTE RECYCLING METHODS

2021 ◽  
pp. 80-89
Author(s):  
Evgeniіa Mykhailova ◽  
Dmytro Deineka ◽  
Hanna Pancheva
Keyword(s):  
Waste Management ◽  
Raw Materials ◽  
Polymeric Materials ◽  
Waste Recycling ◽  
Plastic Waste ◽  
Chemical Recycling ◽  
Mechanical Recycling ◽  
Advantages And Disadvantages ◽  
Secondary Raw Materials ◽  
Plastic Waste Recycling

Methods of plastic waste management, the amount of which is constantly growing due to the high demand for polymer products with high performance properties, are considered. The urgency of the problem is explained by longevity of plastic, which, once in the environment, gradually degrades with the formation of substances dangerous to living organisms. The most common ways of plastic waste management are its storage on specially designated land plots or incineration with / without getting heat. Each of these methods has certain disadvantages, which necessitates the introduction of other measures. Recycling of plastic waste into secondary raw materials, energy or products with certain consumer properties can be the promising method of plastic waste management from ecological and economic points of view. The purpose of this work is to analyze the methods of plastic waste recycling, to establish their advantages and disadvantages, to determine the optimal ways for the disposal of polymeric materials with different properties. Two main groups of polymer recycling methods: physical and chemical, are considered. Physical method includes mechanical recycling, which is based on the physical grinding of plastic waste to obtain secondary raw materials without significant changes in the chemical structure of the material. This process is quite simple in terms of technical design, but requires careful sorting and cleaning of waste, and has limitations on the reuse of recycled material. Chemical recycling takes place through the processes of solvolysis (hydrolysis, glycolysis, alcoholysis) and conversion (pyrolysis, gasification). In this case, the plastic waste decomposes into the original molecules – monomers, from which it is possible to get a polymer product with the same properties. Chemical methods allow disposing of unsorted and contaminated polymeric materials many times without losing their quality. Thus, the introduction of the described methods will reduce the amount of plastic waste, turn them into valuable secondary raw materials and reduce using of natural resources used to obtain primary plastic materials.

Formation and Characterization of Co-Continuous Shear Thickening Fluid/Polymer Blends

2013 ◽  
Author(s):  
Yifeng Hong ◽  
Donggang Yao
Keyword(s):  
Raw Materials ◽  
Chemical Properties ◽  
Shear Thickening ◽  
Polymeric Materials ◽  
Processing Technique ◽  
Melt Processing ◽  
Neat Polymer ◽  
Shear Thickening Fluid ◽  
Continuous Shear ◽  
Physical And Chemical

By synergistically combining distinct physical and chemical properties of different components, co-continuous polymer blending has become an important route to improve the performance of polymeric materials. Shear thickening fluid is a type of non-Newtonian fluid which has unique shear rate dependence and good damping properties. In this work, the authors combined the shear thickening fluid and a commodity polymer into a single system by forming a co-continuous blend via a melt processing technique. The processing window of such co-continuous blend was determined by referring to the thermal and rheological properties of raw materials and experimentally exploring various blending conditions. An increase of tanδ under dynamic mechanical analyzing testing was observed in the co-continuous blend compared with neat polymer as control, which indicated the enhancement of damping capabilities.

Stem Cold Hardiness, Leaf Heat Tolerance, Growth, and Performance of Six Japanese Maples (Acer palmatum) in Northern Illinois

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 512e-512
Author(s):  
A.M. Shirazi
Keyword(s):  
Water Content ◽  
Heat Tolerance ◽  
Cold Hardiness ◽  
Block Design ◽  
Leaf Tissue ◽  
Ion Leakage ◽  
Randomized Block Design ◽  
Leaf Tissues ◽  
Artificial Freezing ◽  
And Performance

Six different Japanese Maples (Acer palmatum) cultivars `Water Fall', `Burgundy Lace', `Crimson Queen', `Oshio-Beni', `SangoKaKu', and `Bloodgood' from Monrovia Nursery were planted in a randomized block design on 4 June 1997 at the The Morton Arboretum. Leaf heat tolerance was evaluated by measuring ion leakage of the leaf tissue at 25–60 °C in July, Aug., and Sept. 1997. The LT50 (the temperature at which 50% of the tissues were injured) of all the cultivars were higher in July (≈53 °C) and were lower in September (≈47 °C). Water content of the leaf tissues were higher in July compare to August and September and were not related to heat tolerance of most cultivars. Stem cold hardiness was performed by artificial freezing tests in Oct., Dec., and Feb. 1997/98. The Lowest Survival Temperature (LST) for the most hardy to least hardy cultivars in October and December were: `Burgundy Lace' (–15, –27 °C), `Bloodgood' (–18, –24 °C), `Oshio-Beni' (–15, –24 °C), `Crimson Queen' (–15, –18 °C), `Water Fall' (–9, –18 °C) and `SangoKaKu' (–9, –12 °C), respectively. Growth, dormancy development, spring budbreak and performance of these cultivars will be compared.

Nanocrystals: The Preparation, Precise Control and Application Toward the Pharmaceutics and Food Industry

2018 ◽  
Vol 24 (21) ◽  
pp. 2425-2431 ◽  
Author(s):  
Cao Wu ◽  
Zhou Chen ◽  
Ya Hu ◽  
Zhiyuan Rao ◽  
Wangping Wu ◽  
...  
Keyword(s):  
Food Industry ◽  
Chemical Properties ◽  
Preparation Methods ◽  
Precise Control ◽  
Significant Process ◽  
Technology Applications ◽  
And Performance ◽  
Physical And Chemical ◽  
Analytical Technology ◽  
And Chemical Properties

Crystallization is a significant process employed to produce a wide variety of materials in pharmaceutical and food area. The control of crystal dimension, crystallinity, and shape is very important because they will affect the subsequent filtration, drying and grinding performance as well as the physical and chemical properties of the material. This review summarizes the special features of crystallization technology and the preparation methods of nanocrystals, and discusses analytical technology which is used to control crystal quality and performance. The crystallization technology applications in pharmaceutics and foods are also outlined. These illustrated examples further help us to gain a better understanding of the crystallization technology for pharmaceutics and foods.

scholarly journals Application of Plastic Wastes in Construction Materials: A Review Using the Concept of Life-Cycle Assessment in the Context of Recent Research for Future Perspectives

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3549
Author(s):  
Tulane Rodrigues da Silva ◽  
Afonso Rangel Garcez de Azevedo ◽  
Daiane Cecchin ◽  
Markssuel Teixeira Marvila ◽  
Mugahed Amran ◽  
...  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Solid Waste ◽  
Building Materials ◽  
Construction Materials ◽  
Plastic Waste ◽  
Plastic Wastes ◽  
Solid Waste Generation ◽  
Alternative Processes

The urbanization process contributes to the growth of solid waste generation and causes an increase in environmental impacts and failures in the management of solid waste. The number of dumps is a concern due to the limited implementation and safe disposal of this waste. The interest in sustainable techniques has been growing in relation to waste management, which is largely absorbed by the civil construction sector. This work aimed to review plastic waste, especially polyethylene terephthalate (PET), that can be incorporated with construction materials, such as concrete, mortars, asphalt mixtures, and paving. The use of life-cycle assessment (LCA) is related, as a tool that allows the sustainability of products and processes to be enhanced in the long term. After analyzing the recent literature, it was identified that studies related to plastic wastes in construction materials concentrate sustainability around the alternative destination of waste. Since the plastic waste from different production chains are obtained, it was possible to affirm the need for a broader assessment, such as the LCA, providing greater quantification of data making the alternative processes and products more sustainable. The study contributes to enhance sustainability in alternative building materials through LCA.

Ionic liquid-assisted biphasic systems for downstream processing of fermentative enzymes and organic acids

2020 ◽  
Vol 6 (3) ◽  
pp. 1-33
Author(s):  
Konstantza Tonova
Keyword(s):  
Organic Acids ◽  
Water Content ◽  
Phase Structure ◽  
Organic Anion ◽  
Chemical Properties ◽  
Downstream Processing ◽  
In Situ Extraction ◽  
Rich Phase ◽  
Biphasic Systems ◽  
Fermentative Products

Abstract Room-temperature ionic liquids (ILs) represent molten salts entirely consisting of ions, usually a charge-stabilized organic cation and an inorganic or organic anion. ILs are liquids at ambient temperature but possess characteristics unusual for the common liquid solvents, such as negligible vapor pressure, high thermal stability and most over the ability to mix and match libraries of cations and anions in order to acquire desirable physical and chemical properties [1]. The opportunity to obtain tunable density, viscosity, polarity and miscibility with common molecular liquids gave rise to a variety of applications of the ILs [2] as environmentally benign solvents, extractants or auxiliaries. In particular, numbers of innovations in the methods for recovery and purification of biologically derived compounds involve ILs used solo or partnered with other liquids in biphasic systems [3,4,5]. It should be noted that the ILs are not intrinsically greener than the traditional solvents, given that their production is usually more resource-demanding, but the inherent potential for recycling and reuse, and for prevention of chemical accidents gives the ILs advantages ahead. The present chapter provides a state-of-the-art overview on the basic applications of the ILs in biphasic systems aimed at downstream processing of valuable fermentative products, enzymes and organic acids. Main industrially important enzymes, lipases and carbohydrases, are considered and a description of the IL-assisted aqueous biphasic systems (ABS) and the results obtained in view of enzyme yield and purity is made. ILs serve different functions in the ABS, main phase-segregating constituents (mostly in the IL/salt ABS) or adjuvants to the polymer/salt ABS. Enzyme isolation from the contaminant proteins present in the feedstock can be carried out either in the IL-rich or in the salt-rich phase of the ABS and for the reader’s convenience the two options are described separately. Discussion on the factors and parameters affecting the enzyme partitioning in the ABS with ILs guides the reader through the ways by which the interactions between the IL and the enzyme can be manipulated in favor of the enzyme purification through the choice of the ABS composition (IL, salt, pH) and the role of the water content and the IL-rich phase structure. The second part of the chapter is dedicated to the recovery of fermentative organic acids. Mostly hydrophobic ILs have been engaged in the studies and the biphasic systems thereof are summarized. The systems are evaluated by the extraction efficiency and partition coefficient obtained. Factors and parameters affecting the extraction of organic acids by ILs are highlighted in a way to unravel the extraction mechanism. The choice of IL and pH determines the reactive mechanism and the ion exchange, while the water content and the IL phase structure play roles in physical extraction. Procedures undertaken to enhance the efficiency and to intensify the process of extraction are also looked over. Finally, the experimental holes that need fill up in the future studies are marked. According to the author’s opinion an intense research with hydrophobic ILs is suggested as these ILs have been proved milder to the biological structures (both the microbial producer and the enzyme product), more effective in the organic acid recovery and suitable to perform “in situ” extraction. Extractive fermentation entails validation of ecological and toxicological characteristics of the ILs. The protocols for re-extraction of fermentative products separated by IL-assisted biphasic systems should be clearly settled along with the methods for ILs recycling and reuse. Novel more flexible approaches to process intensification can be implemented in order to adopt the separation by biphasic systems for use in industry.

Sign in / Sign up

Export Citation Format

Share Document