Expanded Polystyrene Waste Research Articles

Green Synthesis of Multifunctionalized, Nitrogen-Doped, Highly Fluorescent Carbon Dots from Waste Expanded Polystyrene and Its Application in the Fluorimetric Detection of Au3+ Ions in Aqueous Media

Synthesis of highly luminescent carbon dots (CDs) from waste materials gains much attention in the current scenario. We have converted waste expanded polystyrene (EPS), a nonbiodegradable environmental pollutant, into multifunctionalized fluorescent CDs. This can be a good scaling up approach for the large-scale synthesis of nitrogen-doped CDs with a high photoluminescence (PL) quantum yield (QY) of ∼20%. The as prepared CDs exhibit excellent water solubility and a longer PL lifetime (in nanoseconds). They also possess excellent photostability, low cytotoxicity, and stable luminescence QY in different solution environments. Selective and sensitive detection of Au3+ ions is demonstrated using these CDs as fluorescence probes, and a LOD of 53 nM is achieved. A detailed investigation revealed that the observed PL quenching is due to “coordination-induced aggregation caused PL quenching” mechanism.

Characterization of new composite material based on date palm leaflets and expanded polystyrene wastes

In the aim of environmental protection and valorization of vegetal resource, an experimental study on an innovative Wood-Plastic Composite material (WPC) based on Date Palm and expanded Polystyrene, EPS, Wastes is performed. Date palm leaflets waste are used as the reinforcement and EPS waste dissolved in gasoline is used as a matrix. Several combinations of reinforcement sizes (0.1–0.315 mm, 0.315–0.5 mm and 0.5–1 mm) and fiber-to-matrix weight ratios (70, 75 and 80 wt%) were considered to investigate the properties of the Leaflets-Polystyrene Composite (LPC). In this study, physical, mechanical, thermal and morphological characterizations were carried out in order to determine: the bulk density, the flexural modulus, the maximum stress and the thermal conductivity of LPC. Therefore, Pycnometer density measurement, three-point bending test were performed and transient plane heat source (hotdisc) method was used. Furthermore, a characterization by scanning electron microscopy (SEM) was realized to observe the fibers/matrix bond. The LPC showed good adhesion state of the fiber–matrix interface and acceptable mechanical properties with a flexural modulus and a maximum stress that can achieve 0.78 GPa and 2.84 MPa, respectively. The LPC has a density between 542 and 824 kg/m3 which are comparable to those of usual materials like hard-and-soft wood, MDF and other WPC found in the literature. The thermal characterization tests of the LPC have shown also an average thermal conductivity within the range of 0.11 and 0.16 W/m·K. The LPC can be used in the field of building construction as a good thermal insulation as well as a structural component in sandwich structures. Moreover, LPC material is obtained from wastes and can be totally recycled at the end of its useful life.

폐 발포폴리스티렌과 발포폴리스티렌 비드를 활용한 경량 모르타르의 특성

본 논문에서는 발포폴리스티렌 비드 (EPB)와 폐 발포폴리스티렌 (WEP)의 대체율에 따른 경량 모르타르의 기초 특성을 평가였다. EPB 및 WEP를 이용한 경량 모르타르의 기초 특성으로서 단위용적중량, 압축 강도, 휨강도, 흡수율, 열전도율 및 폴리스티렌 (EPB 및 WEP) 분포를 분석하였다. 그 결과 경량 모르타르는 WEP의 대체율이 증가할수록 단위용적중량, 압축 강도, 휨강도, 흡수율 및 열전도율은 증가하고, 폴리스틸렌 면적 분포는 감소하였다. This study presents an evaluation of basic properties of light weight mortar with expanded polystyrene bead(EPB) and waste expanded polystyrene(WEP) by varying replacement rations. In order to evaluate the basic properties of the light weight mortar with EPB and WEP, unit weight, compressive strength, flexural strength, water absorption ratio, thermal conductivity and distribution of polystyrene (EPB and WEP) in hardened mortar were performed. As a result, unit volume, compressive strength, bending strength, water absorption and thermal conductivity of light weight mortar were increased, but area distribution of polystyrene decreased with increasing the replacement ratio of WEP.

Performance Assessment of a Composite Material Based on Kraft Paper and a Resin Formulated with Expanded Polystyrene Waste: A Case Study from Mexico

The present work proposes the recycling of expanded polystyrene (EPS) waste, in order to contribute to reduce the excessive accumulation of this material in sanitary landfills in Mexico. The recovery process of EPS is proposed using a biosolvent (Lemon limonene-LL) to prepare a polymeric solution (EPS-LL), and its subsequent evaluation as a coating on a lignocellulosic Kraft paper of 200 g/m2 and a Gurley porosity of 15–30 seg/100 ml. The effect of different resin concentrations and resin coating layers on the compressive and tensile strength was tested, as well as the resistance of the treated paper to water absorption. Results indicated that the coating layers gradually increased the mechanical strength of the Kraft paper, both tensile and compressive, but only up to a certain grammage of resin applied. Regarding to water absorptiveness, the treated paper showed a significant reduction of water absorption, from 230 g/m2 with one resin layer to 23 g/m2 with three resin layers. The results demonstrate the potential of recycling EPS to obtain a composite material with good hydrophobic characteristics and mechanical strength. This study also intends to provide an added value of this recycled polymer, rather than continuing the current custom of discarding it in sanitary landfills.

The effects of apricot resin addition to the light weight concrete with expanded polystyrene

In this paper, the employability of waste Expanded Polystyrene Foam (EPS) as aggregate in production of concrete with apricot resin-added cement has been examined. The EPS ratios were determined as 20, 40, 60 and 80% of the total volume in the mixtures. The amount of the resin in the mixture is 1% of the weight of the total cement and EPS. At the end of 28 days of drying period, the samples were subjected to certain tests to find out their physical properties. It was seen that the porosity had increased 3.0–26.38% times compared to the case with no resin. Similarly, with increasing the EPS ratio in the mixture from 20 to 80%, the density, thermal conductivity and compressive strength had decreased in the percentages of 14.66–17.61%, 15.49–17.43% and 17.58–40.32% respectively. The rate of water absorption of sample was less than 30%. From this results, it is concluded that these materials can be used as partition walls, floorings, ceiling concretes, briquettes or bricks and plaster instead of building-carrier systems such as columns or beams.

Thermal and mechanical properties of gypsum plaster mixed with expanded polystyrene and tragacanth

In this paper, the employability of waste Expanded Polystyrene Foam (EPS) as filling material in the plaster with resin added gypsum by means of revaluation has been examined. After waste EPS is collected as packaging material and disintegration according to 0–3mm particle diameters and mixed with the gypsum of percentages; 20%, 40%, 60% and 80%. Tragacanth is added to each of this binder at 0.5%, 1% and 1.5% of the weight of the mixture in order to create artificial pores on gypsum block. The samples of 16 different combinations are produces. They are subjected to some tests to find out their properties. It is found that; the thermal conductivity, the compression and tensile strength decreases with increasing amount of EPS and tragacanth in the mixture. Produced samples must not be used in external plaster which is subjected to water against the danger of freezing as the water absorption rate was found higher than 30%. With this study, it is recommended that the samples should be used as internal plaster, insulation plaster and decoration material due to their canal opening and paint sustention features. If this plaster and decoration material is used, (i) the waste EPS will be evaluated and environmental pollution will be prevented, (ii) building heating and cooling energy will be saved.

Green Recycling Approach To Obtain Nano- and Microparticles from Expanded Polystyrene Waste

In this study, we develop a completely green process that could generate a recycled and value added product of polystyrene (PS), such as micro- and nanosized particles, from waste expanded PS (EPS). The process uses the eco-friendly solvent, d-limonene for dissolving waste EPS. We show the first time use of water as a nonsolvent for the recovery of micro- and nanosized PS particles based on an emulsification–diffusion method. Water forms a low boiling azeotrope with d-limonene and reduces the operating temperatures significantly. Poly(vinyl alcohol) (PVA), a water-soluble polymer, is used for stabilizing the oil–water emulsion and to control the particle size. The obtained particles were characterized using scanning electron microscopy, FTIR and dynamic light scattering techniques. Effect of PS and PVA concentrations, stirring speed and oil to water (o/w) ratio on the yield and particle size were investigated. The spent solvent was recovered using a distillation process that was carried out along with the...

Esterification of free fatty acids in non- edible oils using partially sulfonated polystyrene for biodiesel feedstock

Partially sulfonated polystyrene (PSS), synthesized from expanded polystyrene waste (EPS), was used as a catalyst for free fatty acid (FFA) conversion in non-edible oils. Acidic and water absorbing properties of the PSS facilitated the catalytic action for the FFA conversion by esterification reaction. The reaction was done on simulated acid oil (WCO) containing oleic acid and sunflower oil, and rubber seed oil (RSO). Effects of temperature, catalyst amount and alcohol to acid molar ratio were studied. FFA conversion increased with each of these factors. The advantage of this heterogeneous catalyst is that it is efficient as commercial ion exchange resin and easily removable from the reaction mixture. PSS is found to substantially reduce the acid value of WCO and RSO from 17 to 3.2mg KOH/g and from 28.8 to 4.8mg KOH/g respectively at 75°C. The WCO and RSO with reduced acid value may be used as a feedstock for biodiesel production.

Polysel: An environmental-friendly CI engine fuel

Biodiesel was produced herein from the oil contained in waste spent bleaching earth (SBE), an environmental pollutant generated through the refining processes of edible oils in oil extraction plants. To further increase waste utilization, waste expanded polystyrene (EPS) was also dissolved in SBE biodiesel (0, 2.5, 5, and 7.5 g/100 ml). Performance parameters and emission characteristics of 5% blend of EPS-SBE biodiesel and diesel were then investigated in a naturally aspirated diesel engine. The results obtained demonstrated that polymer-free SBE-B5 at 1600 rpm and full load led to enhanced brake power and brake mean effective pressure by approximately 1.5%. Moreover, the emitted HC, CO, and smoke were decreased by over 40%, 80%, and 20%, respectively, with polymer inclusion at 2.5 g/100 ml in SBE-B5 at maximum speed of 2600 rpm and full load (280 N m). While the optimal polymer inclusion level of 2.5 g/100 ml had subtle impacts on engine performance parameters. The findings of the present study could be of great interest to waste valorization industries since an integrated strategy was offered to simultaneously handle two environmental pollutants (SBE oil and EPS wastes) while a more environmentally-friendly fuel blend (i.e., SBE-B5 containing 2.5 g EPS/100 ml) was also achieved.

THE EFFECT OF EXPANDED GLASS AND POLYSTYRENE WASTE ON THE PROPERTIES OF LIGHTWEIGHT AGGREGATE CONCRETE

The main objective of this study is to create a lightweight aggregate concrete (LWAC) with a low thermal conductivity coefficient using expanded glass (EG) aggregate, produced from waste glass or crushed expanded polystyrene waste, obtained by crushing waste packing tare of household appliances. Research related to the effects of the amount of Portland cement (PC) as well as EG aggregates and crushed expanded polystyrene waste on physical (density, thermal conductivity coefficient, water absorption and capillary coefficient) and mechanical (compressive strength) properties of LWAC samples are provided. Insulating LWAC based on a small amount of PC and lightweight EG aggregates and crushed expanded polystyrene waste, with especially low thermal conductivity coefficient values (from 0.070 to 0.098 W/ (m·K)) has been developed. A strong relationship between thermal conductivity coefficient and density of LWAC samples was obtained. The density of LWAC samples depending on the amount of PC ranged between 225 and 335 kg/m3. A partial replacement of EG aggregate by crushed expanded polystyrene waste, results in relative density decrease of LWAC samples. In LWAC samples the increased amount of PC results in increased compressive strength.

Valorisation of waste expanded polystyrene in concrete using a novel recycling technique

This study examines the engineering properties of lightweight aggregate concretes (LWACs) incorporating a novel Expanded Polystyrene (EPS)-based lightweight aggregated called Stabilised Polystyrene (SPS). The SPS aggregate was produced by 80% waste EPS, 10% clay and 10% cement. The influence of the increasing incorporation of SPS on the workability, density, compressive strength, flexural strength, ultrasonic pulse velocity, drying shrinkage, expansion and water absorption (WA) of the different concretes has been investigated. The results showed that the use of SPS enabled to reduce the density of concrete by 8–52% compared to that of the control concrete. The reduction in density was due to the increase in total porosity in the lightweight concretes (LWCs), which also induced higher WA, drying shrinkage and expansion. The 28-day compressive strength of the LWAC was in the range of 4.6–16.4 MPa; thus, the concrete mixture with the higher performances almost satisfied the mechanical and density criteria of structural LWC. These results show that the utilisation of SPS for the manufacture of LWACs is possible.

Properties of concrete containing waste expanded polystyrene and natural resin

In this study, the waste expanded polystyrene (EPS) was used in a mixture of cement and tragacanth resin in order to produce a new concrete material. The amount of the resin in the mixture was 0.5%, 1% and 1.5% of the total cement+EPS. The EPS ratios in the samples were determined as 20%, 40%, 60% and 80% of the total volume.The new samples were subjected to some tests to find out some thermal and mechanical properties. It was concluded that, when EPS ratios and resin ratios of the samples increased, the density, thermal conductivity, compressive strength and tensile strength decreased, and the porosity increased. The change in the physical properties shows that, some artificial pores (except from EPS’s pores) are formed in concrete blocks which allow to increase the insulation characteristic of the material.As a result, it was recommended that; using EPS aggregated and resin-added concrete, (i) the waste EPS can be evaluated and environmental pollution can be prevented, (ii) the new produced samples can be used as partition walls, floorings, ceiling concretes, briquettes or bricks and plaster instead of building-carrier systems such as columns or beams and by this the load of the building can be decreased.

Design of bespoke lightweight cement mortars containing waste expanded polystyrene by experimental statistical methods

This work assesses the reuse of waste expanded polystyrene (EPS) to obtain lightweight cement mortars. The factors and interactions which affect the properties of these mortars were studied by ad-hoc designs based on the d-optimal criterion. This method allows multiple factors to be modified simultaneously, which reduces the number of experiments compared with classical design. Four factors were studied at several levels: EPS type (two levels), EPS content (two levels), admixtures mix (three levels) and cement type (three levels). Two types of aggregate were also studied. The workability, air content, compressive strength, adhesive strength, bulk density and capillary absorption were experimentally tested. The effect of factors and interactions on the properties was modelled and analysed. The results demonstrate how the factors and synergistic interactions can be manipulated to manufacture lightweight mortars which satisfy the relevant EU standards. These mortars contain up to 60% of waste EPS, low amounts of admixtures and low clinker content CEM III. Sustainable mortars containing silica sand gave flow table spread values between 168 and 180±4mm, bulk density between 1280 and 1110±100kg/m3, and C90 between 0.279 and 0.025±0.07kg/m2·min0.5, making them suitable for masonry, plastering and rendering applications.

Microstructural examination and potential application of rendering mortars made of tire rubber and expanded polystyrene wastes

This paper studies the microstructure and potential application of rendering mortars containing tire rubber and expanded polystyrene wastes. The mortars were scanned at the Centre for X-ray Tomography (UGCT – Ghent University) and the μCT images were studied using 3D analysis software package Octopus. The samples’ porosity increased due to the incorporation of the wastes and particularly, expanded polystyrene. Optical microscopy (thin sections) and SEM examination showed that tire rubber particles were not entirely bonded to cement, while expanded polystyrene showed better adhesion to the matrix. In addition, EDS Ca-mapping analysis confirmed expanded polystyrene was almost totally enclosed by a cementitious phase rich in calcium. The practical application of the mortars was tested taking into account the basic requirements applicable to rendering mortars (EN 998-1 standard). Despite the above microstructural limitations, it was found that using low doses of sodium oleate (0.25% w/w) the mortars accomplished the highest performance in terms of capillary water absorption and mechanical strength.

Sintering preparation of porous sound-absorbing materials from steel slag

Porous sound-absorbing materials were prepared from steel slag using waste expanded polystyrene (EPS) particles as pore former. The influences of the experimental conditions such as fly ash content, sintering temperature, sintering time, and pore former addition on the performance of the porous sound-absorbing materials were investigated. The results show that the porosity of the specimens can reach above 50.0%; the compressive strength and average sound-adsorption coefficient of the sintered specimens are above 3.0 MPa and 0.47, respectively. The optimum preparation conditions for the steel slag porous sound-absorbing materials are as follows: mass fraction of fly ash 50%, waste EPS particles 3.6 g, sintering temperature 1100 °C, and sintering time 7.5 h, which are determined by considering the properties of the sound-absorbing materials, energy consumption and cost.

Novel coupling agent between expanded polystyrene waste and natural fabrics

Impregnation of natural fabric with polymeric materials finds wide range of industrial applications. The challenge here is to use wastes to be recycled into useful things. Expanded polystyrene (EPS) was used as the target polymer for impregnation of natural fabrics (jute). Maleic anhydride and abietic acid reacted together to give adduct via Diels Alder reaction. Investigation of the produced maleoabietic adduct was established using Fourier transform infrrared (FT-IR), proton nuclear magnetic resonance (1HNMR) and differential scanning calorimetric (DSC). Expanded polystyrene waste was grafted with the adduct and the product was investigated using thermal gravimetric analysis (TGA) and (DSC). The tensile strength and consequently the adhesion performance between the grafted polystyrene and the jute fabrics were increased upon using maleoabietic as coupling agent. The tensile strength showed abrupt change up to 441 MPa upon using 12 phr maleoabietic.

Thermo-catalytic pyrolysis of polystyrene in the presence of zinc bulk catalysts

Zinc bulk catalysts (Zn, ZnO and ZnCl2) were used for the thermo-catalytic pyrolysis of EPSW and were found with high activity and selectivity of products. Thermo-catalytic pyrolysis was carried out using an efficient Pyrex batch reactor. Zn metal catalyst was found as the best catalyst amongst the zinc bulk catalysts for the cost effective pyrolysis of EPSW (expanded polystyrene waste). The yield of liquid products at 450°C, 120min heating time and 1:0.2 feed to catalyst ratio was 96.73±0.12wt.% with 2.47wt.% toluene, 1.16wt.% ethylbenzene, 47.96wt.% styrene monomer and 1.90wt.% α-methylstyrene. The components of liquid products were separated by fractional distillation and found with further thermal pyrolysis in addition to cyclization and recombination reactions. During the fractional distillation, much product variations were observed. High molecular weight aromatic hydrocarbons decreased with the associated increase of low molecular weight aromatic hydrocarbons, particularly toluene and ethylbenzene.

Properties of wood flour/expanded polystyrene waste composites modified with diammonium phosphate flame retardant

The objective of the study was to evaluate properties of waste plastic composite samples manufactured from expanded polystyrene waste (EPS) and sawdust containing diammonium phosphate (DAP) as flame retardant. Thermal degradation along with dimension stability and mechanical characteristics of the specimens as a function of DAP content were determined. The wood fiber/EPS composite modified with DAP content up to 20 wt% resulted in the best linear burning rate. The rate of thermal degradation of samples also substantially decreased while limiting oxygen index and char residual increased. Overall dimension stability in the form of water absorption and thickness swelling along with flexural characteristics of the samples were found comparable to those of commercial wood plastic composites. The wood fiber/EPS containing DAP showed high potential for use as wood composite products with adequate fire resistance. POLYM. COMPOS., 36:604–612, 2015. © 2014 Society of Plastics Engineers

In Situ Synthesis of CdS Quantum Dot–Partially Sulfonated Polystyrene Composite: Characterization and Optical Properties

A simple, direct method for generating a nanohybrid of CdS quantum dots (QDs) in functionalized waste polymer shows good optical properties combined with photocatalytic activities. Homogeneous sulfonation of expanded polystyrene waste (EPS) forms partially sulfonated polystyrene (PSS). Hydrogelation of the PSS facilitates the attachment of CdS QDs through sulfonic acid groups by ion-exchange mechanism, followed by trapping within the polymer network, ultimately generating an organic/inoganic nanohybrid. X-ray diffraction verifies the existence of the CdS nanocrystals and defines their cubic crystalline structure and crystallite size. High resolution transmission electron microscopy shows the formation of QDs in the nanohybrid. A blue shift in ultraviolet–visible absorption and photoluminescence confirm the QDs formation. The polymer chains effectively passivate the surface of CdS nanocrystals that exhibit exciton emission (455–471 nm) with less surface defect state emission (540 nm). In addition, the photocatalytic activity of the composite in degrading an organic dye is demonstrated.

Lightweight Concrete Incorporating Waste Expanded Polystyrene

This paper covers the results of an experimental investigation on mechanical and durability properties of concrete containing waste polystyrene based lightweight aggregate called Stabilised Polystyrene (SPS) as a partial replacement of natural aggregates. The properties investigated in this paper were water absorption by capillary action and total absorption, compressive strength and ultrasonic pulse velocity (UPV). The composite aggregate was formed with 80% waste polystyrene which was shredded to different sizes, 10% of a natural additive to improve the resistance to segregation and 10% Portland cement. The natural fine aggregate were replaced with 0%, 30%, 60% and 100% (by volume) of SPS. There was an increasing in water absorption and a decreasing in compressive strength and UPV with the increase in SPS aggregate content in concrete.