共查询到19条相似文献,搜索用时 125 毫秒
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论述了塑料包装材料持续,稳步的发展和被广泛应用是时代进步的表征,但其废弃物也对环境带来严重的负面影响。重点就当前国内外对一次性塑料包装材料与环境问题所采取的举措作了介绍和分析,并提出了看法。 相似文献
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扼要评述了塑料包装材料面临环境问题的严峻挑战,并简单评介了塑料包装环境无害化的几种主要处理方法,最后提出加强塑料包装废弃物的综合治理,采取减量,回收,降解等“防与治”相结合的方针对及加强宏观引导,加快立法,增强全民环境和资源意识,可作为我国塑料包装环境无害化的重要对策和措施。 相似文献
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塑料包装废弃物与环境污染 总被引:8,自引:0,他引:8
论述了当前塑料包装材料发展中的机遇和挑战,对我国塑料包装废弃物与环境问题的产生、现状以及正确对待塑料包装废弃物与环境问题进行了分析评述,并提出了主要治理对策和措施. 相似文献
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用LCA法评价纸和塑料包装对环境的影响 总被引:1,自引:0,他引:1
采用国际通用的生命周期分析(LCA)方法.评价了纸和塑料包装对环境的影响。结果表明.不论从能源的消耗.对环境的污染.还是从产品再生循环利用率和可持续发展来看.塑料包装制品都优于纸制品。 相似文献
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塑料制品的过度使用,导致了严重的环境问题。将废旧塑料回收并转化为高附加值的碳材料并用于超级电容器等储能装置有着重要的意义,能够有效地降低环境污染并节约能源。本文首先对超级电容器的应用情况和塑料的使用以及回收处理现状进行了简单叙述,介绍了常见的废弃塑料处理方法、超级电容器的储能特点以及利用废弃塑料制备超级电容器碳材料的潜在价值;接着介绍了多孔碳电极材料的制备方法,对不同的制备方法的具体要求及其优缺点进行了简单分析;随后介绍了几种生活中常见的塑料,按照这些塑料的种类,分别对这些常见塑料回收用作超级电容器碳材料的研究现状进行了详细概述;最后对目前的研究现状进行总结,并对未来的研究方向进行展望。将废弃塑料回收并转化为超级电容器用活性碳材料,是一种新型的废弃塑料回收再利用的有效手段,能够有效地解决白色污染问题。 相似文献
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In this work, results are presented on the application of the dissolution/reprecipitation technique in the recycling of polymers
from waste plastic packaging materials used in food, pharmaceuticals and detergents. Initially, the type of polymer in each
packaging was identified using FT-IR. Furthermore, experimental conditions of the recycling process (including type of solvent/non-solvent,
initial polymer concentration and dissolution temperature) were optimized using model polymers. The dissolution/reprecipitation
technique was applied in the recycling of a number of plastic materials based on polyethylene (LDPE and HDPE), polypropylene,
polystyrene, poly(ethylene terephthalate) and poly(vinyl chloride). The recovery of the polymer was measured and possible
structural changes during the recycling procedure were assessed by FT-IR spectroscopy. Potential recycling-based degradation
of the polymer was further investigated by measuring the thermal properties (melting point, crystallinity and glass transition
temperature), of the polymer before and after recycling, using DSC, their molecular properties (average molecular weight)
using viscosimetry, as well as their mechanical tensile properties. High recoveries were recorded in most samples with the
properties of the recycled grades not substantially different from the original materials. However, a slight degradation was
observed in a few samples. It seems that this method could be beneficial in waste packaging recycling program. 相似文献
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Simona Colantonio Lorenzo Cafiero Doina De Angelis Nicol M. Ippolito Riccardo Tuffi Stefano Vecchio Ciprioti 《Frontiers of Chemical Science and Engineering》2020,14(2):288
A synthetic mixture of real waste packaging plastics representative of the residue from a material recovery facility (plasmix) was submitted to thermal and catalytic pyrolysis. Preliminary thermogravimetry experiments coupled with Fourier transform infrared spectroscopy were performed to evaluate the effects of the catalysts on the polymers’ degradation temperatures and to determine the main compounds produced during pyrolysis. The thermal and catalytic experiments were conducted at 370°C, 450°C and 650°C using a bench scale reactor. The oil, gas, and char yields were analyzed and the compositions of the reaction products were compared. The primary aim of this study was to understand the effects of zeolitic hydrogen ultra stable zeolite Y (HUSY) and hydrogen zeolite socony mobil-5 (HZSM5) catalysts with high silica content on the pyrolysis process and the products’ quality. Thermogravimetry showed that HUSY significantly reduces the degradation temperature of all the polymers—particularly the polyolefines. HZSM5 had a significant effect on the degradation of polyethylene due to its smaller pore size. Mass balance showed that oil is always the main product of pyrolysis, regardless of the process conditions. However, all pyrolysis runs performed at 370°C were incomplete. The use of either zeolites resulted in a decrease in the heavy oil fraction and the prevention of wax formation. HUSY has the best performance in terms of the total monoaromatic yield (29 wt-% at 450°C), while HZSM5 promoted the production of gases (41 wt-% at 650°C). Plasmix is a potential input material for pyrolysis that is positively affected by the presence of the two tested zeolites. A more effective separation of polyethylene terephthalate during the selection process could lead to higher quality pyrolysis products. 相似文献
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基于有限差分方法数值模拟了塑料食品包装材料化学物向食品(模拟物)的迁移及迁移物在食品内的不稳定性。结果表明,扩散系数DP决定了迁移的动力学过程,分配系数KP,F表征平衡时化学物在包装材料和食品内的浓度比值,平衡时食品内的化学物浓度随化学物在包装材料内的初始浓度Cin的增加而增加。对于多层复合包装,阻隔层可显著减缓污染物层内化学物向食品的迁移,从而达到保证食品安全的目的,阻隔层厚度LR影响阻隔功效。化学迁移物在食品内存在不稳定现象,这将导致实验结果低估其向食品的迁移。 相似文献