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烷基酚聚氧乙烯醚(APE)是城市污水的主要污染物之一,在APE的自然降解过程中会产生壬基酚(NP)、短链乙氧基化物和相应的氧化物,如壬基酚乙二醇单醚(NPIE)、壬基酚二乙二醇单醚(NP2E)、壬基酚氧基乙酸(NP2EC)和壬基酚氧基乙氧基乙酸(NP2EC)等。这些产物,特别是NP、NPIE和N2PE的毒性和雌激素活性明显、生物降解性差、亲脂性强、易在污泥和生物体内积累,并可能通过食物链以慢性作用危及所有物种的生存,因此,禁用烷基酚聚氧乙烯醚是减轻环境恶化、保护生态系统的必要措施之一。 相似文献
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壬基酚合成工艺的研究 总被引:1,自引:0,他引:1
以苯酚、壬烯为主要原料合成壬基酚。研究了反应温度、反应时间和催化剂用量等因素对合成反应的影响。结果表明,合成壬基酚的最佳工艺条件为:在常压下,苯酚与壬烯的物料比为1:1.7(摩尔比),反应温度为110℃,反应时间为10小时,催化剂的用量为15%(以苯酚质量份计)。 相似文献
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壬基酚聚氧乙烯醚双子表面活性剂的合成 总被引:1,自引:0,他引:1
以壬基酚、多聚甲醛和环氧乙烷为原料,经3步反应合成了壬基酚聚氧乙烯醚双子表面活性剂(GNP-10),对比了不同固体超强酸催化剂对第二步反应的催化性能。考察了反应条件对2-羟甲基-4-壬基苯酚(化合物Ⅰ)和二-(2-羟基-5-壬基苯基)-甲烷(化合物Ⅱ)的转化率和收率的影响,并对化合物Ⅰ、化合物Ⅱ及 GNP-10的结构进行了表征。实验结果表明,合成GNP-10的适宜条件为:第一步,以氢氧化钠为催化剂、n(壬基酚):n(多聚甲醛)=1:1、反应温度40℃、反应时间12 h、pH 为9,此时壬基酚的转化率为63.1%,化合物Ⅰ的收率为40.2%;第二步,以 SO_4~(2-)/TiO_2固体超强酸为催化剂、n(化合物Ⅰ):n(壬基酚)=1:1、反应温度110℃、反应时间6 h,此时化合物Ⅰ的转化率和化合物Ⅱ的收率分别为73.7%和69.8%;第三步,n(化合物Ⅱ):n(环氧乙烷)=1:20,120~150℃,氢氧化钠催化下反应2 h,GNP-10的收率为98.0%。3步反应的总收率为27.5%。 相似文献
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Hong-Wen Sun Hong-Wei Hu Lei Wang Ying Yang Guo-Lan Huang 《International journal of molecular sciences》2014,15(1):1255-1270
Nonylphenol polyethoxylates (NPnEOs), a major class of nonionic surfactants, can easily enter into aquatic environments through various pathways due to their wide applications, which leads to the extensive existence of their relative stable metabolites, namely nonylphenol (NP) and mono- to tri-ethoxylates. This study investigated the bioconcentration and degradation of NP and NPnEO oligomers (n = 1–12) by a green algae, Chlorella vulgaris. Experimental results showed that C. vulgaris can remove NP from water phase efficiently, and bioconcentration and degradation accounted for approximately half of its loss, respectively, with a 48 h BCF (bioconcentration factor) of 2.42 × 103. Moreover, C. vulgaris could concentrate and degrade NPnEOs, distribution profiles of the series homologues of the NPnEOs in algae and water phase were quite different from the initial homologue profile. The 48 h BCF of the NPnEO homologues increased with the length of the EO chain. Degradation extent of total NPnEOs by C. vulgaris was 95.7%, and only 1.1% remained in water phase, and the other 3.2% remained in the algal cells. The algae removed the NPnEOs mainly through degradation. Due to rapid degradation, concentrations of the long chain NPnEO homologous in both water (n ≥ 2) and the algal phase (n ≥ 5) was quite low at the end of a 48 h experiment. 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(5):676-685
This study investigates the potential migration of plasticisers, plastic components and additives from several plastic water bottles. Compounds studied were phthalates (dimethyl phthalate, di-n-butyl phthalate, benzylbutyl phthalate, bis(2-ethylhexyl) phthalate), bis(2-ethylhexyl) adipate, octylphenol, 4-nonylphenol and bisphenol A. Polycarbonate (PC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS) plastics used in the water bottling sector were tested using three kinds of total or specific migration tests: (1) standard method UNE-EN ISO 177; (2) ultrasonic forced extraction; and (3) standard method UNE-EN 13130-1. In addition, bottled waters contained in different plastic materials were analysed to determine the potential migration of target compounds in real conditions. In all cases, samples were solid-phase extracted using Oasis HLB 200?mg cartridges and analysed using GC-MS in scan-acquisition mode. Bisphenol A and 4-nonylphenol were detected in incubated samples, indicating that migration from food plastics can occur at the experimental conditions tested. The total daily intake was calculated according to the levels detected in bottled water and the assessment of the consumers’ risk was evaluated taking into consideration toxicological and legislative values. 相似文献