scholarly journals Evaluation of LDPE Degradation Under Controlled Composting

Author(s):  
S. Singh ◽  
S. Shankar ◽  
Shikha .

The compost burial test was performed to determine the degradation of commercially available low-density polyethylene in natural compost for a period of six months. Biodegradability of polyethylene films in compost was monitored using scanning electron microscopy (SEM), Energy dispersive X-Ray, Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and weight reduction analysis. After six months of compost exposure, a major change over the surface of LDPE was observed. SEM images clearly showed the exfoliation and cracks on the film leading to degradation. The other analysis also showed a change in the thermal properties and crystallinity of the LDPE films. The composting method could prove to be the reliable and ecological method of degrading plastic waste without hindering the natural ecosystem.

2008 ◽  
Vol 368-372 ◽  
pp. 604-606 ◽  
Author(s):  
Wei Zhong Lv ◽  
Zhong Kuang Luo ◽  
Bo Liu ◽  
Xiang Zhong Ren ◽  
Hong Hua Cai ◽  
...  

Copper ferrite powders were successfully synthesized by sonochemical method. The resultant powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR, differential thermal analysis-thermal gravimetric (DTA-TG), differential scanning calorimetry (DSC) and VSM. The particle saturation magnetization (Ms) is 66 emu/g and an intrinsic coercive force (iHc) is 2100 Oe when the precursor calcined at 950 °C for 15 h.


2013 ◽  
Vol 634-638 ◽  
pp. 2293-2296
Author(s):  
Ai Li Ma ◽  
Cheng Qian Li ◽  
Wu Qing Du ◽  
Jie Chang

In this paper, carbon spheres were synthesized by CVD method. These carbon spheres exhibit diameters of about 200 nm. Thermal gravimetric analysis indicated the good stability in high temperature of the carbon spheres. The products were treated by microwave plasma and high temperature vacuum heat treatments respectively. The products were characterized by X-ray diffraction, Raman spectroscopy and Field Emission Scanning Electron Microscope. The study indicated that the original products, with perfect morphology and low graphitization degree, were converted to crystal. The different techniques were considered for the influence on the graphitization degree.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hamdi Muhyuddin Barra ◽  
Soo Kien Chen ◽  
Nizam Tamchek ◽  
Zainal Abidin Talib ◽  
Oon Jew Lee ◽  
...  

Abstract Synthesis of thermochromic VO2 (M) was successfully done by annealing hydrothermally-prepared VO2 (B) at different temperatures and times. Conversion of the metastable VO2 (B) to the thermochromic VO2 polymorph was studied using thermogravimetric analyzer (TGA) under N2 atmosphere. Moreover, the phase and morphology of the synthesized samples were studied using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), respectively. Accordingly, the XRD scans of all the annealed samples exhibited the presence of monoclinic VO2 (M), while the FE-SEM images of the samples showed the formation of nanorods and nanospheres, particularly those heated at high temperatures (650 °C and 700 °C). Meanwhile, differential scanning calorimetry (DSC) was used to measure the phase transition temperature (τc), hysteresis, and enthalpy of the prepared VO2. Based on these results, all samples displayed a τc of about 66 °C. However, the hysteresis was high for the samples annealed at lower temperatures (550 °C and 600 °C), while the enthalpy was very low for samples heated at lower annealing time (1.5 h and 1 h). These findings showed that crystallinity and nanostructure formation affected the thermochromic properties of the samples. In particular, the sample annealed at 650 °C showed better crystallinity and improved thermochromic behavior.


2016 ◽  
Vol 1133 ◽  
pp. 644-648 ◽  
Author(s):  
Mohamad Azuwa Mohamed ◽  
Wan Norharyati Wan Salleh ◽  
Juhana Jaafar ◽  
Ahmad Fauzi Ismail

Cellulose microfibers (CMF) were produced by utilizing recycled newspaper paper (RNP) as starting material. This approach is considered as green since recycling newspaper leads to the environment preservation and also cost-effective. The effect on the structural properties of cellulose produced at different stage of pretreatment were investigated by using Fourier transform infrared (FTIR), Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Thermal gravimetric analysis (TGA). The FTIR and SEM demonstrate that the hemicellulose and lignin was successfully removed from the structure of the CMF. XRD and TGA results revealed that the different step of pretreatment was increased the crystallinity and thermal stability of CMF increased gradually. The improvement in CMF crystallinity has improved its thermal properties which is important in the field of reinforcement material.


Author(s):  
Viviane Vasques da Silva Guilarduci ◽  
Honória Fátima Gorgulho ◽  
Patrícia Benedini Martelli ◽  
Vanessa Soares dos Santos ◽  
William Graciliano Corrêa

O óleo e a gordura vegetal residual, utilizados para a preparação de alimentos representam um perigoso poluente para as águas de córregos e rios. Um dos métodos mais utilizados nas últimas décadas para limpeza da água oleosa é a aplicação de biossorventes, pois apresentam facilidade para remoção e recuperação do óleo. Neste sentido, o objetivo deste trabalho foi determinar a influência das modificações do bagaço de cana com anidrido acético (acetilação) e com 3-aminopropiltrietoxisilano (silanização) sob a sorção de óleo vegetal. A modificação das fibras foi avaliada pelas técnicas de espectroscopia no infravermelho com transformada de Fourier (FTIR), análise termogravimétrica (TG), difração de raios X, microscopia eletrônica de varredura (MEV) e análise de área superficial e porosidade. Os resultados obtidos indicaram maior sorção de óleo vegetal para o bagaço de cana modificado com anidrido acético (BCA), 667 mg.g-1, seguido pelo bagaço de cana sem modificação (BCN) com sorção de 576 mg.g-1. O bagaço de cana modificado com 3-aminopropiltrietoxisilano (BCS) apresentou menor sorção, 425 mg.g-1, o que foi atribuído à sua maior hidrofilicidade.Evaluation of natural and modified sugarcane bagasse as sorbent of vegetable oil Abstract: The oil and the residual vegetable fat, used for the preparation of foods represent a dangerous pollutant for the waters of streams and rivers. One of the most used methods in the last decades for cleaning the oily water is the application of biosorbents, since they are easy to remove and recover the oil. In this sense, the purpose of this work was to determine the influence of the modifications of sugarcane bagasse with acetic anhydride (acetylation) and with 3-aminopropyltriethoxysilane (silanization) under sorption of vegetable oil. The BCN and the grafted products were further characterized by FTIR spectroscopy, thermal gravimetric analysis, X-ray diffraction, scanning electron microscopy and analysis of surface area and porosity. The results showed higher sorption of vegetable oil for the acetic anhydride-modified sugarcane bagasse (BCA), 667 mg.g-1, followed by sugarcane bagasse without modification (BCN) with sorption of 576 mg.g-1. The cane bagasse modified with 3-aminopropyltriethoxysilane (BCS) presented lower sorption, 425 mg.g-1, which was attributed to its greater hydrophilicity.  


2012 ◽  
Vol 727-728 ◽  
pp. 710-714
Author(s):  
Zélia Maria Peixoto Chrispim ◽  
Luciana Lezira Pereira Almeida ◽  
Izabel de Souza Ramos ◽  
Maria da Gloria Alves ◽  
Jonas Alexandre

The present work was performed in São Fidélis/BR, technologically characterizing four types of soil. Aiming to use them in artistic ceramic, some of their properties were determined, such as the analysis of color after burn. In order to do so, essays regarding their granulometry (sifting and sedimentation), specific gravity, chemical analysis of xray fluorescence, mineralogical identification through x-ray diffraction (DRX), differential thermal analysis (ATD), thermal gravimetric analysis (TG) and scanning electron microscopy (MEV) were carried out in the Laboratories of Universidade Estadual do Norte Fluminense (UENF).The soils were analyzed before drying at 110°C and after burn under temperatures of 750°C and 1,050°C. The analyses of results returned their physical, chemical and mineralogical compositions. Many variations of color could be observed after burn.


2015 ◽  
Vol 749 ◽  
pp. 164-168
Author(s):  
Gamze Bozkurt ◽  
Ayşe Bayrakçeken Yurtcan ◽  
Abdulkadir Özer

In this study, CuO was synthesized via precipitation method by using Cu (CH3COO)2.H2O as precursor. KOH+NH3, KOH and NaOH were used as reactants and zwitterionic 3-(N,N-dimethyldodecylammonio) propane-sulfonate (SB12) as surfactant in the synthesis procedure. The samples were calcined at 500°C. All prepared CuO structures were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), Fourier Transform Infrared (FTIR) spectra, and scanning electron microscopy (SEM) techniques. Electrochemical characterization was performed by cyclic voltammetry (CV). CuO showed different nanostructures according to the characterization results. Furthermore, electrochemical properties of the resulting structures were investigated. The specific capacitances of the CuO structures in different environments were determined by using CV technique in the order of: KOH+NH3>KOH>NaOH.


2017 ◽  
Vol 2017 ◽  
pp. 1-4 ◽  
Author(s):  
Jun Yu ◽  
Huizhong Zhao ◽  
Han Zhang ◽  
Jingjie Li ◽  
Xiongfeng Ding

Various phenolic resins modified with carbon nanofibers were prepared using Fe(NO3)3, Co(NO3)2, and Ni(NO3)3 as catalyst, respectively. The influences of different catalysts on the phase, microstructure evolution, and oxidation resistance of the modified phenolic resin were investigated by X-ray diffraction analysis, field-emission scanning electron microscopy, and thermal gravimetric analysis. The results showed that, compared with a single catalyst, the mixed catalysts (Co(NO3)2 : Fe(NO3)3 = 1 : 1) promoted the growth of the carbon nanofibers, which have the higher crystallinity, homogeneous dispersion, and nonagglomeration. These carbon nanofibers can effectively reduce carbon losses, increase char yield, and fill the holes in the thermal cracking process of phenolic resins.


2021 ◽  
Author(s):  
Lei Mao ◽  
Lijian Pan ◽  
Bomou Ma ◽  
Yong He

Abstract In this research, bio-based polyamide (bio-PA) was synthesized from dimethyl furan-2,5-dicarboxylate and 1,3-cyclohexanedimethanamine by melt polymerization. The properties of bio-PA were analyzed by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA), respectively. The results show that this bio-PA presents high glass transition temperature (Tg) from 150°C to 180°C and poor crystallization due to the asymmetric rigid structure of cyclohexane and furan. Its molecular weight is low, ascribing to the large steric hindrance from cyclohexane and furan, and the side reaction of N-methylation and decarboxylation. Besides, the results of solubility reveal that this bio-PA can be dissolved in DMSO, DMF and DMAC.


2018 ◽  
Vol 19 (2) ◽  
pp. 83
Author(s):  
Jarot Raharjo ◽  
Damisih Damisih ◽  
Ade Utami Hapsari ◽  
Masmui Masmui ◽  
Putri Purnama Yanti

Elektrolit berbasis serium seperti GDC10 telah banyak dikembangkan untuk aplikasi sel bahan bakar oksida padatan suhu sedang atau yang dikenal dengan Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC). Kodoping merupakan salah satu cara untuk meningkatkan konduktivitas elektrolit IT-SOFC. Tujuan dari penelitian ini adalah untuk mempelajari pengaruh penambahan kodopan neodimium (Nd) terhadap GDC10 (Ce0,9Gd0,1-xNdxO1,90) dengan rasio molar x = 0,025; 0,050; dan 0,075 terhadap sifat fisis dan elektrokimianya. Neodimium digunakan sebagai kodopan karena dapat menurunkan energi aktivasi, sehingga konduktivitas elektrolit meningkat. Metode sintesis yang digunakan adalah sol gel untuk menghasilkan serbuk GDC terdoping Nd, setelah itu serbuk dibuat pelet. Sampel dikarakterisasi dengan menggunakan X-Ray Diffraction (XRD) untuk mengidentifikasi fasa, Scanning Electron Microscope (SEM) untuk melihat morfologi dan Thermal Gravimetric Analysis (TGA) untuk melihat stabilitas termalnya. Dari hasil penelitian, kalsinasi pada suhu 700 oC selama 5 jam dan sintering pada suhu 1350 oC selama 2 jam diperoleh densitas pelet elektrolit lebih besar dari 95%. Hal ini telah memenuhi syarat sebagai elektrolit sel bahan bakar padatan yang baik. Keseluruhan sampel memiliki struktur kubik dengan ukuran kristal antara 4,26 nm hingga 4,47 nm. GDC10 terdoping neodimium dengan rasio molar x = 0,025 (GDC-Nd0,025) memiliki konduktivitas tertinggi yaitu 0,055 S/cmpada suhu 600 oC. Hasil tersebut menunjukkan bahwa kodoping dapat meningkatkan konduktivitas sel elektrolit GDC untuk aplikasi sel bahan bakar oksida padatan suhu sedang.


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