首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 93 毫秒
1.
建立了气相色谱-质谱法(GC-MS)及硫化学发光检测气相色谱法(GC - SCD)定性和定量测定炼油厂二硫醚类恶臭污染物二甲二硫、乙基甲基二硫醚和二乙基二硫醚的方法.当进样体积为0.1mL时,GC - SCD法的二硫醚最低检出限为0.1~0.2 mg/m3,二甲二硫和乙基甲基二硫醚的RSD不超过2.4%(n=5),二甲...  相似文献   

2.
以牛磺酸、甲醛和三氯化磷为原料制备了N,N-二膦酰基甲基牛磺酸(BPMT)。探讨了原料配比、反应温度、反应时间对BPMT质量的影响,考察了BPMT的阻垢缓蚀性能,并与N,N-二膦酰基甲基氨基磺酸、N,N-二膦酰基甲基氨基甲磺酸、丙烯酸/2-丙烯酰胺-2-甲基丙磺酸、2-膦酸基-1,2,4-三羧基丁烷等进行了比较。实验结果表明,当n(牛磺酸):n(三氯化磷):n(甲醛)=1:2:4、反应温度110℃、反应时间2h时,BPMT的质量较好。BPMT的阻碳酸钙垢和稳定锌的性能优于其他阻垢剂,阻磷酸钙垢和分散氧化铁的性能仅次于丙烯酸/2-丙烯酰胺-2-甲基丙磺酸。当BPMT加入量为40mg/L时,缓蚀效果最好。  相似文献   

3.
《化工环保》2006,26(4):271-271
该发明提供了一种从苯氨基甲酸酯与甲醛偶联反应的固体混合物中分离提纯二苯甲烷-(4,4’)-二氨基甲酸酯的方法:(1)用一种或多种低碳醇、取代的低碳烷烃或苯系衍生物溶液,在50~150℃下溶解偶联反应后的固体混合物,低碳醇、取代的低碳烷烃或苯系衍生物的质量是固体混合物质量的5~100倍,趁热过滤,分离除去不溶的大分子聚合物和大量的小分子杂质,目标物和其他小分子聚合物、目标物的同分异构体进入溶液,  相似文献   

4.
高艺玮  王国胜 《化工环保》2012,40(4):449-454
使用不同分散剂制备了聚乙烯吡咯烷酮-硫化镉(PVP-CdS)催化剂,研究了盐酸黄连素在PVP-CdS修饰玻碳电极上的电化学行为。实验结果表明:与裸电极相比,PVP-CdS修饰玻碳电极提高了盐酸黄连素的氧化电流;当外加电压为0.5~1.4 V、电位增量为0.018 V、缓冲溶液pH为6时,盐酸黄连素质量浓度在1~200 mg/L的范围内与氧化峰电流呈良好的线性关系,检出限为0.15 mg/L。通过盐酸黄连素氧化前后的红外谱图分析,推断出了氧化机理。  相似文献   

5.
以 6 ,6″-二甲基 - 4′-苯基 - 2 ,2′∶ 6′,2″-三联吡啶 (TPY )为络合剂 ,用分光光度法测定水中铁的含量。进行了波长、TPY乙醇溶液用量及显色时间等条件的选择。该分析方法表观摩尔吸光系数为 2 .17× 10 5 dm3· mol- 1 · cm- 1 ,变异系数为 3.9% ,加标回收率为 96 .4%~ 10 5 .6 %。[关键词 ]6 ,6″-二甲基 - 4′-苯基 - 2 ,2′∶ 6′,2″-三联吡啶 ;分光光度法 ;铁 ;水质分析以 6 ,6″-二甲基 - 4′-苯基 - 2 ,2′∶ 6′,2″-三联吡啶 (TPY )为络合剂 ,用分光光度法测定水中铁的含量。进行了波长、TPY乙醇溶液用量及显色时间等条件的选择。该分析方法表观摩尔吸光系数为 2 .17× 10 5 dm3· mol- 1 · cm- 1 ,变异系数为 3.9% ,加标回收率为 96 .4%~ 10 5 .6 %。  相似文献   

6.
研究了在聚乙二醇-200(PEG-200)活化下,Cu^2+催化H2O2氧化亚甲基蓝的褪色反应,建立了亚甲基蓝褪色催化动力学光度法测定痕量Cu^2+的方法。在25mL容量瓶中,加入1.00mL pH为11.68的氨水溶液、2.00mLH2O2溶液(质量分数15%)、1.00mL亚甲基蓝溶液(质量浓度0.20mg/mL)、3.00mL PEG~200溶液,76℃恒温反应5min后冷却,测定吸光度,根据加Cu^2+溶液和不加Cu^2+溶液的吸光度差值与Cu^2+质量浓度绘制了工作曲线,并由试样的吸光度差值确定痕量Cu^+含量。该法的测定波长为664nm,检出限为5.4×10^-6 g/L,最大相对标准偏差为2.58%,回收率为97.5%~104.5%。  相似文献   

7.
以K2S2O8-脲为引发剂,通过自由基聚合法合成了丙烯酰胺-2-甲基丙烯酰氧乙基三甲基氯化铵P(AM—DMC)絮凝剂,并研究了其对4种活性染料模拟废水的脱色效果,考察了P(AM—DMC)加入量、阳离子度、特性粘数、染料溶液pH等因素对脱色效果的影响。实验结果表明:最佳P(AM—DMC)加入量随染料分子中磺酸基数目的增加而增加,随絮凝剂阳离子度的增大而减少;阳离子度大于52%时,最高脱色率基本相同;特性粘数对脱色效果影响很小;在染料溶液为弱酸性及中性条件下,P(AM—DMC)的脱色效果较好。P(AM—DMC)对活性染料废水的脱色机理是,P(AM—DMC)中的-N^+(CH3)3与染料分子中的-SO3^-结合,生成-N^+(CH3)3SO3^-,同时也形成了分子间氢键,通过键合作用使染料分子聚集沉降。  相似文献   

8.
选取了6种有代表性的挥发性有机化合物(VOCs),异丙醇、二氯甲烷、乙酸乙烯酯、正己烷、苯和四氯化碳,实测了这些VOCs在气体采样罐(SUMMA罐)中的存储稳定性。结果表明:苯、正己烷和二氯甲烷在采样罐中均较稳定,其含量在84 d的存储期内基本无变化;乙酸乙烯酯在6个VOCs中最不稳定,在普通和惰性采样罐中含量均明显下降;异丙醇和四氯化碳的稳定性与采样罐的类型有关,在普通采样罐内含量下降明显,而在惰性采样罐内则相对稳定。实际监测工作中,为提高VOCs分析的准确性,如目标分析物有含氧类(醇,酮,酯等)或含卤素类VOCs,则采样后需尽快分析,同时尽量选择惰性采样罐为采样容器。  相似文献   

9.
赵雪娜 《化工环保》2016,36(2):189-192
对模拟碳纤维生产废水进行“厌氧-好氧”静态小试,根据COD的去除效果确定该碳纤维废水的可生化性。采用“二级厌氧-微氧-好氧”组合工艺进行动态中试,考察废水的处理效果及系统的抗冲击性能。试验结果表明:该工艺对碳纤维生产废水的处理效果较好;系统具有厌氧池出水pH增大的特点,且抗冲击能力较强;在厌氧池水温为28~38 ℃、好氧池水温不低于15 ℃、废水流量为100 L/h、进水COD为660 mg/L、进水ρ(氨氮)为4.9 mg/L的条件下,出水COD稳定在50 mg/L以下,ρ(氨氮)稳定在5 mg/L以下,能够满足GB 8978-1996《污水综合排放标准》的要求。  相似文献   

10.
有机-无机离子型杂化高效絮凝剂   总被引:1,自引:0,他引:1  
《化工环保》2005,25(3):238-238
该发明涉及一种有机-无机离子型杂化高效絮凝剂。其原料组成质量分数为:氢氧化物胶体0.5%~15%;丙烯酰胺50%~95%;阳离子型单体0~45%。所述氢氧化物胶体包括:氢氧化铝、氢氧化铁、氢氧化镁、氢氧化锌,其胶体粒径为10~200nm。所述阳离子型单体包括:N,N-二甲基二烯丙基氯化铵(DMDAAC)或(甲基)丙烯酰氧乙基三甲基氯化铵(DMC)。通过无机、有机间的离子键合在带电荷的无机胶体微粒表面原位聚合形成丙烯酰胺/阳离子单体的共聚物制备的有机-无机杂化高效絮凝剂,充分发挥无机絮凝剂的电中和及有机高分子的架桥作用,使其药效能协同发挥,形成的絮体大而密实,絮体抗剪切性好,沉降速度快,其絮凝效率显著提高,可减小药剂的投放量,大幅度降低废水处理的成本,出水达到国家排放标准。/CN1554592,2004—12—15  相似文献   

11.
The fermentative production of 1,3-propanediol (1,3-PDO) by Klebsiella pneumoniae under different initial substrate concentrations (between 5 and 110 g/L) was investigated. It was found that glycerol was almost 100% utilized and 1,3-PDO production increased up to 20 g/L of influent substrate concentration, but there was a significant decrease in both glycerol consumption and 1,3-PDO production at substrate concentrations exceeding 20 g/L. Furthermore, pH control was essential, and a lack of pH control negatively effects of 1,3-PDO production. In the second part of the study, two microorganisms, namely Clostridium beijerinckii NRRL B593 and K. pneumoniae were comparatively studied in terms of their 1,3-PDO productivity under pH controlled conditions. Higher 1,3-PDO production was achieved under pH controlled fermentation conditions (pH = 7) for both microorganisms. Even though the two microorganisms had almost the same 1,3-PDO yield (0.60 mol/mol for C. beijerinckii, 0.61 mol/mol for K. pneumoniae) at the end of fermentation period, K. pneumoniae completed the 1,3-PDO production in one-third of the time (t = 8 h with a productivity of 1.34 g/L/h) than C. beijerinckii (t = 24 h). The results of this study clearly indicated that a substrate inhibition is a challenge that needs to be studied further for higher productivities.  相似文献   

12.
Responding to environmental, sustainability, business, and market factors, DuPont has commercialized a new polymer platform, Sorona®, based on 1,3-propanediol. The physical and chemical property advantages over other polymers are described. The diol component of this polymer, 1,3-propanediol, has been demonstrated to be manufacturable via biological (fermentation) process from corn sugar. The economic, environmental, and process/product quality advantages of bio-PDO over conventional diols are discussed.  相似文献   

13.
Journal of Polymers and the Environment - Biobased poly(1,3-propylene 2,5-furandicarboxylate) (PPF) and carbon nanotubes (CNTs) nanocomposites were prepared by a solution and coagulation method at...  相似文献   

14.
Mao  Lei  Pan  Lijian  Ma  Bomou  He  Yong 《Journal of Polymers and the Environment》2022,30(3):1072-1079
Journal of Polymers and the Environment - In this research, bio-based polyamide (bio-PA) was synthesized from dimethyl furan-2,5-dicarboxylate and 1,3-cyclohexanedimethanamine by melt...  相似文献   

15.
Sorption capacities were evaluated for the dissolved stormwater (SW) pollutants onto two tree mulches and jute fiber. SW spiked with predetermined concentrations of copper (Cu), cadmium (Cd), hexavalent chromium (Cr +6), lead (Pb), zinc (Zn), and benzo[a]pyrene (B[a]P), naphthalene (NP), fluoranthene (FA), 1,3‐dichlorobenzene (DCB), and butylbenzylphthalate (BBP) were used in this study. Each medium removed close to 100 percent of all the pollutants at the concentrations studied. Sorption capacities (μg/g) of the three organic media were in the order of jute > hardwood mulch > softwood mulch, and on a mole basis, both the heavy metals and the toxic organics were sorbed by the three media in an identical sequence: Cr +6 > Cu, Zn > Cd > Pb; and NP > DCB > FA > B[a]P > BBP. Sorption capacities of the hardwood wood mulch and jute fiber for the pollutants were correlated with distinctive physical properties of the pollutants. © 2005 Wiley Periodicals, Inc.  相似文献   

16.
任晓光  李富霞  李鹏 《化工环保》2013,33(3):259-262
采用浸渍法制备了不同NiO和CuO质量分数的NiO-CuO/ZSM-5催化剂,并以CH4为还原剂研究了NiO-CuO/ZSM-5催化剂对催化裂化烟气的脱硫脱硝活性。XRD分析结果表明,NiO质量分数为4%、CuO质量分数为6%的催化剂4%NiO-6%CuO/ZSM-5中的ZSM-5结构完好,CuO和NiO高度分散在ZSM-5骨架中,表明具有较好的催化活性。4%NiO-6%CuO/ZSM-5的脱硫脱硝起活温度均较低,无氧条件下最高NO转化率和SO2转化率分别为94.7%和95.9%,O2体积分数为1.0%时的NO转化率和SO2转化率分别为97.7%和89.0%。  相似文献   

17.
The recently isolatedPseudomonas sp. A33 was investigated for the production of a highly unsaturated polyhydroxyalkanoate (PHA) containing various alkyl and alkenyl pendent groups from 1,3-butanediol in a cell-recycle fed-batch production mode. The monomer composition and degree of unsaturation in PHA were dependent on the environmental conditions. The production temperature markedly influenced the content, composition, and degree of unsaturation of PHA. As the production temperature decreased from 30 to 10°C, the degree of unsaturation and content of PHA were increased, while the mole percentage of 3-hydroxybutyrate (3HB) was decreased. These temperature effects on the composition of PHA imply that the production can be used as a control variable for the biosynthesis of a highly unsaturated PHA and for the specific regulation of the composition of PHA. The biosynthetic pathway for a highly unsaturated PHA which is based on de novo fatty acid biosynthetic pathway is proposed. For the enhanced production of this functional PHA, a high cell density was achieved by cell-recycle continuous culture at 30°C, and then a large amount of PHA was accumulated at 15°C by fed-batch addition of the feeding solution containing excess 1,3-butanediol. The structures of monomer constituents of polymer were confirmed by gas chromatography—mass spectrometric analysis of trimethylsiyl derivatives of 3-hydroxyalkanoic acids methyl esters.  相似文献   

18.
Fungal degradation of 6:2 fluorotelomer alcohol (6:2 FTOH, C6F13CH2CH2OH) by two wood‐decaying fungal strains and six fungal isolates from a site contaminated with per‐ and polyfluoroalkyl substances (PFASs) was investigated. 6:2 FTOH is increasingly being used in FTOH‐based products, and previous reports on the microbial fate of 6:2 FTOH have focused on bacteria and environmental microbial consortia. Prior to this study, one report demonstrated that the 6:2 FTOH biotransformation by the wood‐decaying fungus, Phanerochaete chrysosporium, generated more polyfluoroalkyl substances, such as 5:3 acid (F(CF2)5CH2CH2COOH), and diverted away from producing the highly stable perfluorocarboxylic acids (PFCAs). Most of the fungi (Gloeophyllum trabeum and isolates TW4‐2, TW4‐1, B79, and B76) examined in this study showed similar degradation patterns, further demonstrating that fungi yield more 5:3 acid (up to 51 mol% of initial 6:2 FTOH dosed) relative to other metabolites (up to 12 mol% total PFCAs). However, medium amendments can potentially improve 6:2 FTOH biotransformation rates and product profiles. The six fungal isolates tolerated up to 100 or 1,000 milligrams per liter of perfluorooctanoic acid and perfluorooctane sulfonic acid, and some isolates experienced increased growth with increasing concentrations. This study proposes that fungal pathways must be considered for the biotransformation of potential PFAS precursors, such as 6:2 FTOH, and suggests the basis for selecting proper microorganisms for remediation of fluoroalkyl‐contaminated sites.  相似文献   

19.
In this study we investigated the cometabolic oxidation of six cyclic ethers by alkane‐grown Mycobacterium vaccae JOB5. These ethers include, among others, tetrahydrofuran (THF), 1,4‐dioxane (14D), 1,3‐dioxolane (13DO), and tetrahydropyran (THP). Cells grown on propane, n‐butane, n‐pentane, isobutane, or isopentane oxidized all six ethers. Ether‐degrading activity was inhibited by acetylene in alkane‐grown cells and was largely absent from cells grown on dextrose‐containing media. Propane competitively inhibited THF oxidation. γ‐Butyrolactone (γBL) accumulated and was also further oxidized during THF oxidation by propane‐grown cells. In contrast, no products were detected during 14D oxidation. Propane‐grown cells also rapidly oxidized 3‐hydroxytertrahydrofuran and exhibited strong hemiacetal‐oxidizing activity in an assay following methyl formate production from mixtures of methanol and formaldehyde. These observations suggest γBL is likely generated during THF oxidation through further oxidation of 2‐hydroxytetrahydrofuran. Limited growth of strain JOB5 was supported by several cyclic ethers and the corresponding lactones and diols potentially derived from these compounds. However, strain JOB5 grew more readily on 4‐hydroxybutyrate, the product of γBL hydrolysis. The ability of strain JOB5 to productively assimilate THF‐derived metabolites during growth on n‐alkanes was examined in carbon‐limited batch cultures. Relative to C‐limited growth on n‐pentane alone, culture growth increased up to twofold in the presence of THF while no stimulation of growth was observed in comparable experiments conducted with n‐pentane and 14D. Our results are discussed in terms of their significance to our understanding of cyclic ether cometabolism and their potential impact on approaches for cyclic ether biodegradation in the environment. © 2013 Wiley Periodicals, Inc.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号