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Jingli Wu Tianju Chen Xitao Luo Dezhi Han Zhiqi Wang Jinhu Wu 《Waste management (New York, N.Y.)》2014,34(3):676-682
The pyrolysis and co-pyrolysis behaviors of polyethylene (PE), polystyrene (PS) and polyvinyl chloride (PVC) under N2 atmosphere were analyzed by Thermal gravimetric/Fourier transform infrared (TG/FTIR). The volatile products were analyzed to investigate the interaction of the plastic blends during the thermal decomposition process. The TGA results showed that the thermal stability increased followed by PVC, PS and PE. The pyrolysis process of PE was enhanced when mixed with PS. However, PS was postponed when mixed with PVC. As for PE and PVC, mutual block was happened when mixed together. The FTIR results showed that the free radical of the decomposition could combine into a stable compound. When PE mixed with PVC or PS, large amount of unsaturated hydrocarbon groups existed in products while the content of alkynes was decreased. The methyl (CH3) and methylene (CH2) bonds were disappeared while PVC mixed with PE. 相似文献
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Kuniyasu Kawaguchi Kazutada Miyakoshi Kiyoshi Momonoi 《Journal of Material Cycles and Waste Management》2002,4(2):102-110
It is important to investigate the pyrolysis processes of municipal solid waste (MSW) in the same way as for any mixture
comprised of multiple substances. In this article, a two-reaction model for a variety of MSW mixtures is proposed to predict
mass changes due to pyrolysis. In order to formulate the model based on pyrolysis kinetics, we conducted experiments to determine
the kinetic model parameters. By thermal analysis of the typical components of MSW, mass changes attributable to the pyrolysis
reaction were found at about 350°C for paper, 400°–500°C for plastics, and 200°–400°C for garbage (dry condition). Activation
energies were obtained by the Ozawa method based on the mass changes in pyrolysis. Thus, the pyrolysis behavior is formulated
as a function of temperature. Then the pyrolysis mass change of the mixture can be predicted by using a weighted sum of the
individual components. The model proved useful in experiments with real waste (refuse-derived fuels). Furthermore, the weight
yields (pyrolysis gas, tars, solid residues) of the mixture can be calculated by their additive property after measuring the
mass balance of each component.
Received: May 11, 2001 / Accepted: November 16, 2001 相似文献
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地球环境中普遍存在的纳米孔与有机质的相互作用对资源和环境领域许多重要科学问题(如有机质的吸附与保存、油气的赋存与采收以及二氧化碳的地质封存等)起着关键作用。然而,目前关于纳米孔特别是微孔(<2 nm)与有机质作用的系统研究还比较少。本文选择实验室合成的Stber二氧化硅作为模拟矿物微孔,采用热红联用技术(TG/DSC-FTIR)来研究其与系列有机溶剂(乙醇、正丙醇、正丁醇、正庚醇)作用后的热化学性质。结果表明,乙醇和正丙醇较易进入Stber二氧化硅微孔(孔径0.8 nm)。在NH_3催化作用下,醇与孔内外硅羟基发生烷氧基化作用,孔外烷氧基的脱除温度随着溶剂碳链增加而降低,放热效应逐渐增强;相反,孔内烷氧基的脱除温度随碳链增加而增加,放热效应逐渐减弱。在无NH_3存在条件下,由于烷氧基化作用减弱,乙醇与正丙醇能在孔内游离存在,孔内烷氧基的脱除温度随溶剂碳链增加呈下降趋势。Stber二氧化硅的微孔结构直接影响了醇类有机质在不同气氛下的热解行为,甲烷、乙烯、丙醛等分子的逸出也为纳米孔隙结构束缚下的有机质的深部热行为提供了参考。 相似文献