...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Deutsche Lebensmittel-Rundschau >Recycling of post-consumer poly(ethylene terephthalate) for direct food contact application - a feasibility study using a simplified challenge test
【24h】

Recycling of post-consumer poly(ethylene terephthalate) for direct food contact application - a feasibility study using a simplified challenge test

机译：消费后聚对苯二甲酸乙二醇酯的回收，用于直接接触食品的应用-使用简化挑战试验的可行性研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The question of recyclability of post-consumer poly(ethylene terephthalate) PET into new packaging materials for direct food contact is still an active part of research. In order to protect consumers' health, effective recycling processes and economic challenge tests to verify the cleansing efficiency of these processes are necessary. The aim of this work was to draw up a modified challenge test scheme for PET material from used soft drink bottles as recycling substrate. The intention was to make the test more economic as well as environmentally and user-friendly compared to proposed FDA test schemes and to apply the challenge test to a commercial recycling process for PET. The recycling process consists essentially of three steps including (i) conventional washing of PET flakes, (ii) remelting and extrusion of PET granules and (iii) additional solid- phase post-condensation of the PET granules. With the aid of several model contaminants possessing different physico-chemical properties, the purification efficiency of each step of the recycling process was determined. The challenge test was carried out at three different contamination levels, i. e. applying three different initial concentrations. In comparison to the initial contaminant (surrogate) concentrations as recommended by the FDA guidelines the actually applied concentrations of the surrogates in our challenge tests are equivalent. It could be shown that soaking of the PET flakes in excessive volumes of solvents and the washing step before remelting as proposed by FDA is not necessarily to be carried out. This reduces the amount of used chemicals and hazardous waste significantly. As expected, there is a great different in the removal potential of the process for volatiles compared to non-volatile substances. Volatile substances are already efficiently removed by the normal remelting/extrusion step to form granules. For the non-volatile compounds a conventional extrusion process decreases concentrations of these compounds in the granules only such that 50% to 25% of the initial concentrations was remained in the PET material. The additional post-condensation step leads to a further decrease of the surrogates. For the most challenging surrogate, benzophenone, only 8% of the initial concentration was found in the post-condensed final product. The overall cleansing efficiency of the whole PET recycling process (inclusive washing of the PET material) was found to be more than 99% for the most challenging surrogate. Given cleansing efficiencies as obtained in this study and taking account of real-life contamination levels which are expected to be much lower than those applied to the challenge test, the qualities of recycled PET material can be expected such that they fulfill the legal requirements given by the US-FDA threshold-of-regulation principle. Consequently, such PET recyclate qualities should be suitable again for direct food contact applications.
机译：将消费后的聚对苯二甲酸乙二醇酯PET制成可直接与食品直接接触的新包装材料的可回收性问题仍然是研究的重要内容。为了保护消费者的健康，必须进行有效的回收过程和经济挑战测试以验证这些过程的清洁效率。这项工作的目的是针对用过的软饮料瓶作为回收基质的PET材料制定一种改良的挑战测试方案。与FDA提议的测试方案相比，其目的是使测试更经济，更环保，更易于使用，并将挑战性测试应用于PET的商业回收过程。再循环过程主要包括三个步骤，其中包括（i）PET薄片的常规洗涤，（ii）PET颗粒的重熔和挤出以及（iii）PET颗粒的额外固相后缩合。借助几种具有不同理化特性的模型污染物，确定了回收过程中每个步骤的净化效率。挑战测试是在三种不同的污染水平下进行的，即e。应用三种不同的初始浓度。与FDA指南建议的初始污染物（替代物）浓度相比，在我们的挑战试验中实际应用的替代物浓度是等效的。可以证明，不必按照FDA的建议将PET薄片浸泡在过量的溶剂中并在重熔之前进行洗涤步骤。这样可以大大减少化学药品和危险废物的使用量。如所预期的，与非挥发性物质相比，该方法对挥发性物质的去除潜力有很大差异。挥发性物质已通过常规的重熔/挤压步骤有效地去除，形成颗粒。对于非挥发性化合物，常规的挤出方法仅降低颗粒中这些化合物的浓度，使得PET材料中保留了初始浓度的50％至25％。额外的后冷凝步骤导致替代物的进一步减少。对于最具挑战性的替代物，二苯甲酮，在缩合后的最终产物中仅发现初始浓度的8％。对于最具挑战性的替代产品，发现整个PET回收过程的整体清洁效率（包括PET材料的洗涤）超过99％。鉴于本研究获得的清洁效率并考虑到实际生活中的污染水平预计将远低于挑战试验所采用的水平，因此可以预期回收的PET材料的质量应使其符合美国-FDA的监管门槛原则。因此，这种PET回收物质量应再次适合直接接触食品的应用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号