Study of thermal property changes of biopol/polyamide 11 blends during biodegradation in compost

Polymer blends of poly(β-hydroxybutyrate-co-b-hydroxyvalerate) (Biopol) with polyamide 11, possessing copolyester continuous phase, were degraded during 25 weeks in compost. The biodegradation was followed by mass loss and melting enthalpy measurements. The degradability was primary dependent on the hydroxyvalerate content in the blend. This revised version was published online in July 2006 with corrections to the Cover Date.     

松香生产废水的内电解处理技术研究*

研究采用内电解法处理松香生产废水的反应条件和处理效果,并用气相色谱法对内电解处理过程中废水有机成分的变化进行分析.试验结果表明,内电解反应的最佳反应条件为:反应时间9~11 h,pH范围3.5~5,铁屑投加量为60 g/600 mL废水.另外,实验数据还表明,内电解处理可提高松香废水的可生化性.     

二氧化碳共聚物为基的聚氨酯生物降解性能研究

以CO2为起始物合成出聚碳酸亚乙酯（PEC）二醇，进而合成以PEC为预聚物的聚氨酯。对该聚氨酶的力学性能、降解性能等进行了测试。结果表明，该聚氨酯同时具有良好的力学性能和良好的生物降解性能。     

Modelling of ready biodegradability based on combined public and industrial data sources

ABSTRACT

The European Registration, Evaluation, Authorization and Restriction of Chemical Substances Regulation, requires marketed chemicals to be evaluated for Ready Biodegradability (RB), considering in silico prediction as valid alternative to experimental testing. However, currently available models may not be relevant to predict compounds of industrial interest, due to accuracy and applicability domain restriction issues. In this work, we present a new and extended RB dataset (2830 compounds), issued by the merging of several public data sources. It was used to train classification models, which were externally validated and benchmarked against already-existing tools on a set of 316 compounds coming from the industrial context. New models showed good performances in terms of predictive power (Balance Accuracy (BA) = 0.74–0.79) and data coverage (83–91%). The Generative Topographic Mapping approach identified several chemotypes and structural motifs unique to the industrial dataset, highlighting for which chemical classes currently available models may have less reliable predictions. Finally, public and industrial data were merged into global dataset containing 3146 compounds. This is the biggest dataset reported in the literature so far, covering some chemotypes absent in the public data. Thus, predictive model developed on the Global dataset has larger applicability domain than the existing ones.     

高浓度鱼油精炼废水混凝处理及可生物降解性试验研究

采用pH调节与混凝法对高浓度鱼油精炼废水进行预处理 .结果表明 :聚合氯化铝 (PAC)在pH为 5 .5和投加量为 90mg·L- 1 时可以有效去除废水中的各种污染物 ,出水具有较好的可生物降解性 .     

微电解法处理染化废水的试验研究

染化废水污染物种类多,毒性大、化学需氧量,ρ(CODcr)高,且大部分是生物难降解的污染物质,严重污染环境;利用铁炭在水中发生的微电解过程可有效去除染料生产废水的色度和化学需氧量ρ(CODcr),同时提高污水的后续可生化性.试验结果表明,微电解处理效果受填料组成、pH值、停留时间和混凝曝气等因素的影响;废水经过微电解处理后,ρ(CODcr)和色度分别从2 000 mg/L和2 048下降为860 mg/L和256,去除率可高达56％和75％;采用微电解-混凝法出水与采用单纯的石灰乳中和混凝沉淀法出水相比,ρ(CODcr)降低22.5％,可生化性提高18％.     

含酚废水的太阳光/Fenton氧化预处理技术

研究了模拟含酚废水的太阳光/Fenton 氧化预处理技术.结果表明,含酚废水经过适当程度的太阳光/Fenton氧化预处理后,不仅可去除废水的部分COD,还可显著提高废水的混凝性能及可生化性.COD为710.4 mg/L的苯酚废水,直接进行混凝处理时,COD的去除率仅为14.3%,单纯采用太阳光/Fenton氧化处理(氧化剂H2O2的用量为150mg/L)时COD去除率为32%,而采用太阳光/Fenton氧化预处理— 混凝法联合工艺处理后,COD的去除率可达到62.1%,远大于单纯混凝与单纯太阳光/Fenton氧化处理效果之和.实验结果还表明适当程度的太阳光/Fenton 氧化预处理可明显提高苯酚废水的可生化性,使废水的 BOD5/CODCr比值由0.10提高到0.32.     

生物降解性阻垢剂聚环氧琥珀酸的合成及其阻垢性能研究

探讨了生物降解性阻垢刺聚环氧琥珀酸的合成条件和阻垢性能．结果表明：聚合反应中，在冠醚存在下，醇钠催化生成的聚合物具有较好的阻垢性能．催化剂一定，反应时间、温度、催化剂用量和药剂添加量也影响阻垢性能。当环氧化时间为1．5h，聚合温度为60℃，冠醚用量为1．O％，阻垢剂用量为4mg／L时，阻垢率达95．3％．     

Lipase-catalyzed synthesis and properties of poly[(12-hydroxydodecanoate)-co-(12-hydroxystearate)] directed towards novel green and sustainable elastomers

Novel green and sustainable elastomers having both good biodegradability and chemical recyclability properties were designed and synthesized using potentially biobased materials and lipase as an environmentally benign catalyst. High molecular weight poly[(12-hydroxydodecanoate)-co-(12-hydroxystearate)] [poly(12HD-co-12HS)] samples with varying monomer ratios were prepared by the polycondensation of 12-hydroxydodecanoic acid and methyl 12-hydroxystearate using immobilized lipase from Candida antarctica (IM-CA) in toluene in the presence of molecular sieves 4A at 90 degrees C. Although poly(12HD) is a highly crystalline polyester having a melting temperature (T(m)) of 87.6 degrees C and crystalline temperature (T(c)) of 64 degrees C, by the copolymerization of 12HD with 12HS, both the T(m) and T(c) of the copolymer decreased with increasing 12HS contents, and poly(12HD-co-12HS) containing more than 60 mol-% 12HS was a viscous liquid at room temperature. At the same time, the Young's modulus and hardness also decreased with increasing 12HS content, and poly(12HD-co-36 mol-% 12HS) exhibited an elastic behavior, having a hardness of 70 A using a durometer A. In addition, it showed an excellent biodegradability by activated sludge and chemical recyclability by lipase.     

Optimizing the synergistic effect of sodium hydroxide/ultrasound pre-treatment of sludge

Ultrasound (ULS), sodium hydroxide (NaOH) and combined ultrasound/NaOH pre-treatment were applied to pre-treat waste activated sludge and improve the subsequent anaerobic digestion. Synergistic effect was observed when NaOH treatment was coupled with ultrasound treatment. The highest synergistic Chemical Oxygen Demand (COD) solubilization was observed when 0.02M NaOH was combined with five minutes ultrasonication: an extra 3000 mg/L was achieved on top of the NaOH (1975 mg/L) and ultrasonication (2900 mg/L) treatment alone. Further increase of NaOH dosage increased Soluble Chemical Oxygen Demand (SCOD), but did not increase the synergistic effect. Nine and 18 minutes ultrasonication led to 20% and 24% increase of methane production, respectively; Whereas, 0.05M NaOH pre-treatment did not improve the sludge biodegradability. Combined ultrasound/NaOH (9 min+0.05 M) showed 31% increase of methane production. A stepwise NaOH addition/ultrasound pre-treatment (0.02M+ULS for 5 min+0.02M+ULS for 4 min) was tested and resulted in 40% increase of methane production using 20% less chemicals.