A study of vapour-liquid equilibria for the binary mixtures hcfc22/cfc114, hcfc22/hcfc142b and hcfc22/hfc152a

Experimental data for vapour liquid equilibrium for the three non-azeotropic mixtures HCFC22ICFC114 (CHClF_z/C_zCl_zF₄), HCFC22IHCFC142b (CHClF_z/C_z,/H₃ClF_z) and HCFC221HFC152a (CHClF_z/C_zH₄F_z) and vapour pressure for the pure components have been measured in pressure range up to 1.8 MPa. In a comparative study the deviations between experimental and calculated data for three correlation methods are presented. The three methods are the equations of state according to Lee-Kesler (1975) and Carnahan-Starling-de Santis (1976) and the activity coefficient model by Wilson (1964). Interaction parameters have been fitted from experimental data to the mixing rules proposed to the two equations of state and the activity coefficient parameters have been determined in the Wilson (1964) model. All three methods studied give good conformity with experimental data for the three mixtures examined.     

有机阻燃剂最新进展

论述９０年代卤系阻燃剂领域内的关注热点和卤系、磷系、卤－磷系及膨胀型阻燃剂在近几年内的发展动态。     

Synthesis and characterization of brominated polyester composites

Two unsaturated polyesters containing a halogen (bromine) in the backbone of the polymer chain were synthesized and compared with a halogen‐free polyester. The bromine content was measured by elemental analysis. The chemical structures of the polyesters were characterized by means of IR and ¹H‐NMR spectroscopies. Feldspar was used as the filler to form the polyester composites. The effects of the halogen substituents, filler concentration, and crosslinking monomers and comonomers on the electrical and mechanical properties of the polyester composites were studied. The flammability was also investigated. The styrenated polyesters and their composites achieved fire resistance and good mechanical and electrical properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1356–1365, 2006     

阻燃尼龙的研究进展

介绍阻燃聚酰胺工程塑料(尼龙)以及适于其阻燃的阻燃剂。阐述了卤系阻燃剂,磷系阻燃剂,氮系阻燃剂,金属化合物阻燃剂及它们复合协效对聚酰胺阻燃的研究进展。     

水解酸化—MBR—臭氧处理卤化丁基橡胶废水

采用水解酸化-MBR-臭氧组合工艺处理卤化丁基橡胶废水,研究组合工艺对COD、NH4^+-N、石油类、挥发酚以及有机卤化物(AOX)的处理效果。结果表明,组合工艺对COD、NH4^+-N、石油类、挥发酚及AOX均有较好的处理效果,去除率分别高达95.13%、99.20%、95.42%、99.64%和93.72%,出水COD≤60 mg/L,NH4^+-N、石油类、挥发酚、AOX的质量浓度分别≤8、≤5、≤0.5、≤1 mg/L,出水水质满足GB 31571-2015排放要求。     

聚氨酯泡沫阻燃剂浅谈

介绍了在聚氨酯泡沫塑料中常用的阻燃剂,包括反应型阻燃剂和添加型阻燃剂。着重对市场上部分卤代磷酸酯阻燃剂的类型进行了介绍。简要介绍了阻燃剂的阻燃机理、聚氨酯泡沫塑料用阻燃剂的研究开发,对我国聚氨酯用阻燃剂的发展提出建议。     

页岩油气储层压裂返排液中卤代烃的吹扫捕集-气相色谱/质谱法检测

在页岩油气开采中,化学示踪技术可以有效应用于评价储层压裂改造效果。化学示踪剂技术推广应用的先决条件在于其相应的分析检测方法。通过研究筛选出了21种化学性质稳定、地层背景值低的卤代烃作为示踪剂,建立了基于吹扫捕集气相色谱-质谱联用（GC-MS）的高灵敏度检测方法。对吹扫捕集、气相色谱-质谱条件进行了优化并获得了最佳条件。结果表明：方法的检出限为0.027~0.162 μg/L,基体加标回收率在74.16%~121.9%之间,精密度（相对标准偏差RSD,n=7）小于12.79%。该方法简单、快捷,适用于页岩油气储层压裂液中所述卤代烃示踪剂的检测。     

Potential toxicity and implication of halogenated byproducts generated in MBR online-cleaning with hypochlorite

Online chemical cleaning of membrane bioreactor (MBR) with sodium hypochlorite (NaClO) has been extensively applied for membrane fouling mitigation. However, it was recently revealed that residual NaClO from the online cleaning of MBR caused serious microbial lysis with the subsequent formation of dissolved organic matter (DOM), in which a substantial level of halogenated byproducts was detected. Different from those generated in potable water chlorination, most of the halogenated byproducts generated during MBR online cleaning with hypochlorite belonged to the haloaromatic family, which were apparently more toxic than aliphatic compounds. It was shown that a substantial amount of the generated halogenated byproducts passed through the microfiltration membrane and entered the surface waters through the discharge of MBR permeate. As such, the concentration of halogenated byproducts might likely reach an alarming level via bioaccumulation in the aquatic environment. This emerging situation indeed poses serious concerns for the aquatic environment, water supply and public health due to significantly high toxicity of haloaromatic compounds produced. Unfortunately, the potential halogenated byproducts-associated environmental risks have not been carefully and systematically assessed towards the establishment of relevant regulations. Therefore, this review attempted to fill up such a gap by providing the insights into the potential environmental impacts of halogenated byproducts in the MBR permeate. © 2019 Society of Chemical Industry     

Brominated,chlorinated and mixed brominated/chlorinated persistent organic pollutants in European eels (Anquilla anquilla) from Latvian lakes

Fifty-eight European eel (Anquilla anquilla) specimens collected from five Latvian lakes were investigated for six groups of persistent organic pollutants (POPs), including polychlorinated, polybrominated and mixed bromo-chloro dibenzo-p-dioxins and dibenzofurans (PCDD/DFs, PBDD/DFs and PXDD/DFs), polychlorinated and mixed bromo-chloro biphenyls (PCBs and PXBs) and polybrominated diphenyl ethers (PBDEs). PCDD/DFs and PCBs were found to occur in the range 0.85–15.8 pg Total-WHO₂₀₀₅-TEQ g^?1 f.w., and concentrations in most of the samples were below the maximum levels specified in European Commission Regulation (EU) No. 1259/2011. The summed concentrations of 27 PBDEs (∑_PBDE) and 16 non-dioxin-like PCBs (∑_NDL-PCB) were in the ranges of 0.28–26.7 and 6.37–320 ng g^?1 f.w., respectively. PBDD/DFs, PXDD/DFs and PXBs show average upper-bound concentrations of 0.05, 0.06 and 0.01 pg TEQ f.w. and collectively contributed 3.4% to the sum TEQ of dioxin-like compounds. The highest contaminant concentrations were measured in samples from lakes near the Baltic Sea and the industrialised area near Riga (Liepajas and Kisezers lakes). A correlation of POP concentration with the length of collected specimens was observed.     

卤代芳胺合成的研究进展

本文综述了由卤代芳硝基物还原制备卤代芳胺的三种方法,并对几种还原方法的优缺点进行了对比和讨论,得出水合肼还原具有很好的应用前景。