Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland.
Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland.
Waste Manag. 2023 Aug 1;168:413-422. doi: 10.1016/j.wasman.2023.06.022. Epub 2023 Jun 22.
Despite the increasing interest in bioplastics, there are still contradictory results on their actual biodegradability, which cause difficulties in choosing and developing appropriate sustainable treatment methods. Two biofoils (based on poly(butylene succinate) (PBS) and cellulose (Cel)) were anaerobically degraded during 100-day mesophilic (37 °C) and thermophilic (55 °C) tests (PBS, Cel). To overcome low degradation rates in mesophilic conditions, alkaline pre-treatment was also used (Pre-PBS, Pre-Cel). For comprehensive understanding of biodegradability, not only methane production (MP), but also the structure (topography, microscopic analysis), tensile properties, and FTIR spectra of the materials undergoing anaerobic degradation (AD) analysed. PBS and Pre-PBS were visible in 100-day degradation, and the cumulative MP reached 25.5 and 29.3 L/kg VS, respectively (4.3-4.9% of theoretical MP (TMP)). The biofoils started to show damage, losing their mechanical properties over 35 days. In contrast, PBS was visible for 14 days (cracks and fissures appeared), cumulative MP was 180.2 L/kg VS (30.2% of the TMP). Pieces of Cel were visible only during 2 days of degradation, and the MP was 311.4-315.0 L/kg VS (77.3-78.2% of the TMP) at 37 °C and 319.5 L/kg VS (79.3% of the TMP) at 55 °C. The FTIR spectra of Cel and PBS did not show shifts and formation of peaks. These findings showed differences in terms of the actual biodegradability of the bioplastics and provided a deeper understanding of their behaviour in AD, thus indicating limitations of AD as the final treatment of some materials, and also may support the establishment of guidelines for bioplastic management.
尽管人们对生物塑料越来越感兴趣，但它们的实际生物降解性仍存在相互矛盾的结果，这给选择和开发合适的可持续处理方法带来了困难。两种生物箔（基于聚丁二酸丁二醇酯（PBS）和纤维素（Cel））在 100 天的中温（37°C）和高温（55°C）试验（PBS、Cel）中进行了厌氧降解。为了克服中温条件下的低降解率，还使用了碱性预处理（Pre-PBS、Pre-Cel）。为了全面了解生物降解性，不仅分析了甲烷产量（MP），还分析了材料在厌氧降解（AD）过程中的结构（形貌、微观分析）、拉伸性能和傅里叶变换红外光谱（FTIR）。在 100 天的降解过程中可以看到 PBS 和 Pre-PBS，累积的 MP 分别达到 25.5 和 29.3 L/kg VS（理论 MP（TMP）的 4.3-4.9%）。生物箔在 35 天内开始出现损坏，失去机械性能。相比之下，PBS 在 14 天内可见（出现裂缝和裂缝），累积的 MP 为 180.2 L/kg VS（TMP 的 30.2%）。Cel 的碎片仅在降解的 2 天内可见，MP 为 311.4-315.0 L/kg VS（TMP 的 77.3-78.2%）在 37°C 和 319.5 L/kg VS（TMP 的 79.3%）在 55°C。Cel 和 PBS 的 FTIR 光谱没有显示位移和峰的形成。这些发现表明生物塑料的实际生物降解性存在差异，并提供了对其在 AD 中行为的更深入了解，从而表明 AD 作为某些材料的最终处理方法存在局限性，并且还可以为生物塑料管理指南的制定提供支持。
