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 共查询到19条相似文献,搜索用时 140 毫秒
1.
聚苯乙烯基硫代磺酸钾树脂的合成及其与卤代烃的反应   总被引:2,自引:2,他引:0  
吴萼  刘秀芬 《环境化学》1998,17(3):237-242
由聚苯乙烯基磺酰氯树脂与硫化氢钾反应制备聚苯乙烯基硫代磺酸钾树脂(I),树脂I与亲电的卤代烃反应,生成聚苯乙烯基硫代磺酸酯树脂(Ⅱ),树脂Ⅱ经过乙硫醇处理,使卤代烃结构部分以不对称二硫醚的形式游离下来,用GC/MS对其结构进行鉴定。从不对称二硫醚的结构可推导出原卤代烃的结构,所制备的聚苯乙烯基硫代磺酸钾树脂的转化效率为1.11mmol·g^-1。  相似文献   

2.
带希夫碱和酰肼基团的壳聚糖螯合树脂的合成及其吸附性能   总被引:21,自引:1,他引:21  
刘芳  董世华 《环境化学》1996,15(3):207-213
本文利用壳聚糖C2位上活泼氨基与水杨醛进行大分子反应,再以环硫氯丙烷作交联剂,合成了带有邻羟基希夫碱基团的交联型壳聚糖螯合树脂;利用带有游离氨基的交联壳聚糖与丙烯腈进行大分子反应,合成了带有氰基的功能聚合物,再由CT-CN与水合肼进一步反应,制得了带有酰肼基轩物壳聚糖螯合树脂。  相似文献   

3.
吴萼  尹京花 《环境化学》1998,17(5):467-472
用改进的方法合成了对甲苯磺酰肼基二硫代甲酸钾。以它作模型化合物,在酸性条件下加热解,放出二硫化碳,被二乙胺及醋酸铜的混合液吸收,生成黄色荒氨酸铜,在430nm波长比色,从而建立了定量测定磺酰肼基二硫代甲酸基团的方法。  相似文献   

4.
螯合淀粉衍生物对铜离子吸附性能的研究   总被引:12,自引:0,他引:12  
相波  李义久  倪亚明 《环境化学》2004,23(2):193-197
以玉米淀粉为原料,经交联、间接醚化、胺化反应合成了交联氨基淀粉(CAS),CAS进一步与CS2亲核加成反应,合成了带有二硫代氨基甲酸(DTC)基团的DTC改性淀粉(DTCS).研究了CAS和DTCS吸附铜离子的动力学行为,结果表明,二者对铜的吸附均符合Freundlich等温式.298K时,CAS和DTCS的吸附速率常数分别为κ=1.758h^-1和κ=10.32h^-1.根据对吸附行为的研究得到了表观动力学方程和热力学参数,并藉助IR和元素分析及吸附平衡研究了吸附机理.  相似文献   

5.
二硫代氨基甲酸盐型除油剂的性能研究   总被引:3,自引:0,他引:3  
葛际江  赵福麟  冷强 《环境化学》2002,21(2):162-166
分别用二乙胺、乙二胺、三乙烯四胺与CS2 反应 ,合成了三种二硫代氨基甲酸盐 ,试验了其除油性能 .结果表明 ,三 ( 1 ,2 亚乙基 )四氨基四 (二硫代甲酸钠 )对含有一定量Fe2 + 的油田污水有较好的除油效果 .每升污水中加入 1 0mg除油剂 ,就能在1 5min内将污水中的油含量降至 1 0mg·l- 1.通过改变二硫代氨基甲酸盐的浓度、污水中Fe2 + 的浓度、搅拌速度、氨基的结构 ,发现多官能团的二硫代氨基甲酸盐 ,在较低的搅拌速度下 ,除油效果较好 .  相似文献   

6.
杀虫丹系杀虫双农药单钠盐结晶体的商品名,它是沙蚕毒系农药新品种(化学名:2-N-二甲胺基-1-硫代磺酸钠基,3-硫代硫酸基丙  相似文献   

7.
吴萼  刘秀芬 《环境化学》1998,17(5):462-466
由卤代次甲基化合物标样分别民对甲苯代磺酸钾、对甲苯亚磺酸钠及对甲苯磺酰在二硫代甲酸进行反应,发现化合物3与标样反应最快,因此,通过三步反频将该基因接枝到聚苯乙烯白球上,  相似文献   

8.
曹海峰  吴萼 《环境化学》1998,17(3):243-249
本文用聚苯乙烯基硫代磺酸钾树脂为选择性试剂与水中卤代物作用,排除水体中其它化合物对结构分析的干扰,采用动态恒温柱法及C-18柱富集法作为该反应发生的途径,结果表明:前一种途径的检测结果由样品反应活性决定,而后者检测结果还受到萃取率的影响,两种方法均可达到10-20mg·l^-1的检测水平。  相似文献   

9.
交联壳聚糖乙酸酯冠醚对金属离子的吸附性能研究   总被引:9,自引:1,他引:8  
本文合成了二苯并-16-冠-5-氯代乙酸酯冠醚和3,5-二叔丁基-二苯并-14-冠-4-双氯代乙酸酯冠醚,然后分别将之与交联壳聚糖(简称CCTS)反应,制备了交联壳聚糖二苯并-16-冠-5-乙酸酯冠醚(简称CCTS-1)和交联壳聚糖3,5-二叔丁基-二苯并-14-冠-4-双乙酸酯冠醚(简称CCTS-2),并研究了它们对Pb~(2+),Cu~(2+),Cr~(3+),Ni~(2+),Cd~(2+)的吸附性能。结果表明:这两种吸附剂对pb~(2+),Cu~(2+)有较高的吸附选择性。  相似文献   

10.
提出了一种有机胺吸收二氧化硫的烟气脱硫工艺.采用填充柱常压吸收常压再生操作流程,以解吸率和有效吸收SO2容量为评价指标,研究了哌嗪水溶液的脱硫性能,并将其与甲基二乙醇胺(MDEA)和乙二胺(EA)溶液作了比较.实验表明,0.3-0.5m01.1-1的哌嗪水溶液在30℃的温度下能达到较佳的吸收效果,而在85℃的温度下解吸能有效地减少富液挥发损失并达到95%以上的解吸率.哌嗪水溶液的单位有效脱硫容量达到了3.49g·g-1,远高于MDEA和EA.  相似文献   

11.
针对硝基苯污染底泥修复的活性覆盖技术,筛选了适合阻断底泥中硝基苯释放的还原剂和吸附剂.采用的零价铁可迅速将难生物降解的硝基苯还原为苯胺,提高其生物可降解性,有利于将污染物彻底去除.零价铁对硝基苯的还原反应速率随着零价铁剂量的提高而提高,反应速率常数≥>10.001 min~(-1).吸附试验结果表明,在煤渣、活性炭、焦炭以及硅藻土几种常见的吸附剂中,活性炭具有最佳的吸附能力,但是其价格昂贵,不适于大规模应用.而廉价易得的煤渣对硝基苯及其降解产物苯胺具有良好的吸附性能,对硝基苯和苯胺的最大理论吸附量达到924.9 mg·kg~(-1)和1692.2 mg·kg~(-1).因此提出以煤渣为吸附基质,并添加一定比例零价铁的复合活性覆盖材料,为硝基苯污染底泥修复提供一种新的方向和基本参数.  相似文献   

12.
Arsenic contamination of water is a major problem worldwide. A possible solution can be approached through developing new sorbents based on cost-effective and environmentally friendly natural biomaterials. We have developed new sorbents based on biomaterial impregnation with iron oxyhydroxide. In this study, raw peat material, iron-modified peat, iron-modified biomass (shingles, straw, sands, cane and moss) as well as iron humate were used for the removal of arsenate from contaminated water. The highest sorption capacity was observed in iron-modified peat, and kinetic studies indicated that the amount of arsenic sorbed on this material exceeds 90 % in 5 h. Arsenate sorption on iron-modified peat is characterised by the pseudo-second-order mechanism. The results of arsenic sorption in the presence of competing substances indicated that sulphate, nitrate, chloride and tartrate anions have practically no influence on As(V) sorption onto Fe-modified peat, whereas the presence of phosphate ions and humic acid significantly lowers the arsenic removal efficiency.  相似文献   

13.
The global consumption and production of pharmaceuticals is increasing concomitantly with concern regarding their environmental fate and effects. Active pharmaceutical ingredients are mainly released into the aquatic environment through wastewater effluent discharge. Once in the environment, pharmaceuticals can undergo processes of natural attenuation, i.e. dilution, sorption, transformation, depending on physico-chemical properties of the compound, such as water solubility, lipophilicity, vapour pressure, and environmental conditions, such as pH, temperature and ionic strength. A major natural attenuation process is the sorption on dissolved organic matter, colloids, suspended solids and sediments, which in turn control pharmaceuticals distribution, residence time and persistence in aquatic systems. Here we review studies of sorption capacity of natural sorbents to pharmaceuticals. These report on the importance of several environmental and sorbent-specific properties, such as the composition, quality, and amount of the sorbent, and the environmental pH, which determines the speciation of both the sorbent and compound. The importance of accounting for distribution processes on freshwater sorbents for any determination of environmental concentrations of pharmaceuticals is apparent, while the reliability of surrogate standards for measuring dissolved organic matter (DOM) distribution is evaluated in the context of the need for robust environmental risk assessment protocols.  相似文献   

14.
Pyrolyzing sludge into biochar is a potentially promising recycling/disposal solution for municipal wastewater sludge, and the sludge-derived biochar (SDBC) presents an excellent sorbent for metal immobilization. As SDBC is composed of both mineral oxides and carbonized organic compartment, this study therefore compared the sorption behaviour of Pb and Zn on SDBC to those of individual and mixture of activated carbon (AC) and amorphous aluminium oxide (Al2O3). Batch experiments were conducted at 25 and 45 °C, and the metal-loaded sorbents were artificially aged in the atmosphere for 1–60 days followed by additional sorption experiments. The Pb sorption was generally higher than Zn sorption, and the co-presence of Pb reduced Zn sorption on each studied sorbent. Higher sorption capacities were observed at 45 °C than 25 °C for SDBC and AC, while the opposite was shown for Al2O3, indicating the significance of temperature-dependent diffusion processes in SDBC and AC. Nevertheless, metal sorption was more selective on Al2O3 that showed a greater affinity towards Pb over Zn under competition, correlating with the reducible fraction of sequential extraction. Furthermore, significant amounts of Pb and Zn were additionally sorbed on SDBC following 30-day ageing. The X-ray diffraction revealed the formation of metal-phosphate precipitates, while the X-ray photoelectron spectroscopy showed a larger quantity of metal–oxygen bonding after 30-day ageing of metal-loaded SDBC. The results may imply favourable long-term transformation and additional sorption capacity of SDBC. In conclusion, SDBC resembles the sorption characteristics of both organic and mineral sorbents in different aspects, presenting an appropriate material for metal immobilization during soil amendment.  相似文献   

15.
A systematic kinetic study of phosphorus (P) sorption by various materials in the soil infiltration system of septic tanks was undertaken by following the time course of P sorption by sorbents in contact with various P solutions over periods up to 360 days. Uptake of P seemed to consist of two distinct stages. Initial uptake was very rapid and this phase was completed in 4 days or less. A slower removal stage followed for some materials over many months. Phosphorus sorption during the fast reaction stage appeared to be associated with the soluble Ca content of the materials. The fast reaction of calcareous materials accounted for the bulk (>70%) of the total P removed. Merribrook loamy sand exhibited the highest proportion of P sorption during the slow phase. It should be noted, however, that for solution P concentrations in the range found in typical effluents (∼ ∼20 mg L−1) the fast reaction phase seemed to be responsible for virtually all P removed. None of the six kinetic formulae examined possessed the sophistication and detail needed to portray accurately the time course of P sorption for all the sorbents investigated. The Elovich equation and the kinetic modification of the Freundlich isotherm expression appeared to provide a reasonable fit of the experimental data.  相似文献   

16.
疏水性有机污染物在土壤/沉积物中的赋存状态研究   总被引:5,自引:0,他引:5  
孙红文  张闻 《环境化学》2011,30(1):231-241
土壤/沉积物是环境中有机污染物主要的汇,由于土壤-沉积物结构和性质的复杂性,有机污染物进入其中,会结合在不同的位点上,赋存状态发生分化,具有不同的物理流动性、生态风险和化学反应活性.对于土壤-沉积物中有机污染物吸附/解吸的研究是认识其赋存状态并预测其生态风险的重要手段.本文对于疏水性污染物吸附/解吸及赋存状态的国内外研...  相似文献   

17.
生物炭吸附有机污染物的研究进展   总被引:21,自引:0,他引:21  
生物炭(biochar)是指生物质在缺氧条件下热裂解产生的一种产物.由于其精致的孔隙结构和独特的表面化学性质,对环境介质中的有机污染物有超强的吸附能力,进而影响污染物的迁移与归宿.近年来生物炭对有机污染物的吸附特性及机理研究已成为环境科学领域的研究热点之一.本文从生物炭的典型性状、吸附有机污染物的机理、影响因素以及对土壤中有机污染物生物可给性的影响等方面进行了综述,并提出生物炭吸附有机污染物未来的研究方向.  相似文献   

18.
The ability of pine bark and almond shells to remove bisphenol A (BPA) from aqueous solutions was evaluated. Samples of these traditional agro-forestry by-products were milled, sieved into different particle size fractions (0.10–0.15 and 1.5–2.0 mm) and submitted to two different types of treatment. Sorption experiments were conducted in a batch system at room temperature and natural pH. Sorption equilibrium was attained after 48 h for all systems under study. Bisphenol A was adsorbed more effectively on the smaller particles of the sorbents. Pine bark and almond shell pretreated with formaldehyde presented higher sorption efficiency (95%), followed by almond shell (87%) and pine bark (82%) washed with hot water. All the sorption isotherms were found to fit a Freundlich equation, with correlation coefficients (R 2) between 0.823 and 0.989. The sorption coefficient (K F) ranged from 0.06 to 0.74 (mg1?1/n ·L 1/n ·g ?1). These results indicate that utilisation of both materials as an alternative sorbent for the removal of bisphenol A from contaminated waters is promising because they are available in large amounts and have an acceptable cost–efficiency ratio when compared with traditional adsorbents.  相似文献   

19.
Samples with the best adsorption properties are selected as a result of investigations conducted on synthesis of manganese-dioxide-based materials and study of their physicochemical properties. Materials were selected on the basis of their low cost and the simplicity of their production technology. In the laboratory the synthesis and analyses of materials was carried out for selected samples. The sorption of a series of elements is studied for a more detailed investigation of materials obtained. The results obtained will promote the synthesis of materials with improved adsorption properties with the aim of their application for purification of water from strontium. It is shown that the most promising way for amendment of manganese oxide is modification of this material using acid-resistant oxides. These oxides are also less expensive than existing sorbents for strontium.  相似文献   

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