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1.
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   

2.
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   

3.
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   

4.
《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   

5.
稀土Gd掺杂SnO2-Sb涂层阳极电催化氧化甲基橙   总被引:2,自引:2,他引:0  
采用溶胶-凝胶法,以无机盐SnCl4·5H2O,Sb2O3,Gd(NO3)3为前驱体,制备了稀土Gd掺杂SnO2-Sb涂层阳极。以稀土Gd掺杂SnO2-Sb为阳极电催化氧化处理甲基橙溶液,考察了电解质浓度、电流密度、溶液的pH、溶液温度及稀土Gd掺杂对甲基橙降解率的影响。实验结果表明:稀土Gd掺杂SnO2-Sb涂层阳极对甲基橙具有较好的降解效果。在电解质NaCl质量浓度为4g/L、电流密度为0.06A/cm2、甲基橙溶液的pH为3、溶液温度为25℃条件下,氧化降解1.0h甲基橙降解率为92.21%,氧化降解2.5h甲基橙降解率为99.15%。  相似文献   

6.
磷酸铵镁沉淀法处理氨氮废水及沉淀剂的回用   总被引:3,自引:2,他引:1  
用磷酸铵镁沉淀法处理氨氮废水,在pH为8.5、反应时间为20min、n(PO4^3-):n(Mg^2+):n(NH4^+):1.2:1.1:1的最佳条件下,氨氮去除率为97.6%。采用加入足量饱和Ca(OH)2溶液的方法,可使上层清液中多余的Mg^2+与PO4^3-形成Mg(OH)2和Ca3(PO4)2沉淀,离心后再用浓硫酸溶解,可达到回用的目的,而处理后上层清液中剩余磷酸盐质量浓度低于1mg/L,达到GB8978-1996《污水综合排放标准》中第二类污染物国家二级排放标准的要求。所得MgNH4PO4沉淀用加热碱溶方法回用,MgNH4PO4沉淀的回用次数小于6时,氨氮去除率在80%左右;所得MgNH4PO4沉淀用加酸溶解方法回用,氨氮去除率最高为35%。  相似文献   

7.
微波-改性活性炭-Fenton试剂氧化法降解水中2,4-二氯酚   总被引:7,自引:2,他引:5  
以经Fe2(SO4)3溶液浸渍改性的活性炭作催化剂、Fenton试剂作氧化剂,采用微波-改性活性炭-Fenton试剂氧化法降解水中的2,4-二氯酚。考察了改性活性炭加入量、H2O2与Fe^2+摩尔比、Fenton试剂加入量、微波功率和2,4-二氯酚溶液初始pH对2,4-二氯酚降解效果的影响。在改性活性炭加入量1.0g/L、n(H2O2):n(Fe^2+)=16.7(H2O2加入量6.0mmol/L、Fe^2+加入量0.36mmol/L)、Fenton试剂加入量为6.36mmol/L、微波功率600W、微波辐射时间10min、2,4-二氯酚溶液初始pH为6.0的条件下,2,4-二氯酚降解率和TOC去除率分别可达98.7%和84.0%。  相似文献   

8.
新兴污染物BP-3和BP-4的好氧生物降解性能   总被引:1,自引:0,他引:1       下载免费PDF全文
采用欧洲经济合作与发展组织(OECD)的生物降解测试标准方法——301F测压呼吸计量法,考察了2-羟基-4-甲氧基二苯甲酮(BP-3)和2-羟基-4-甲氧基二苯甲酮-5-磺酸(BP-4)的好氧生物降解性能,并研究了降解动力学及共代谢现象。实验结果表明:BP-3和BP-4的可生物降解率分别为68.36%和41.34%;根据OECD快速降解性判定标准,BP-3划归为易快速降解物质,而BP-4为不易快速降解物质;两种物质的生物降解可用一级动力学描述,半衰期分别为1.986 d和2.806 d;根据欧盟法规《化学品的注册、评估、授权和限制》(REACH法规),BP-3和BP-4均非持久性物质;与苯甲酸钠共存时,BP-3和BP-4的降解过程均表现出共代谢现象。  相似文献   

9.
庞卫锋   《化工环保》2008,28(1):89-92
用泰德拉气体采样袋采样,自动进样气相色谱法测定气体中的非甲烷烃含量。甲烷、总烃的线性范围分别为0~2439,0—2066mg/m^3。进样量为1mL时,检出限为0.02mg/m^3(信噪比为3)。对3种不同浓度甲烷与丙烷混合标准气进行测定,重复性相对标准偏差为0.4%-1.0%。对4种不同性质的试样进行加标回收实验,加标回收率为96.7%-102.0%。5名实验人员分别用自动进样法及手动进样法分析4种不同性质的试样,自动进样法的重现性相对标准偏差为1.2%~1.8%,优于手动进样法的6.5%~8.3%。该法可一次连续测定21个试样,精密度高、重现性好、分析效率高。  相似文献   

10.
卢姝  李昕 《化工环保》2008,28(1):85-88
用高效液相色谱法分析精对苯二甲酸残渣,考察了适宜的操作条件。实验结果表明,在采用阴离子交换柱作分析柱,浓度为0.2mol/L的磷酸二氢铵缓冲液为流动相、体积分数为10%的甲醇作有机改性剂、用磷酸调试样pH为6—7、检测波长为240nm的最佳条件下,分离效果最好,对羧基苯甲醛、苯甲酸、对甲基苯甲酸、邻苯二甲酸、对苯二甲酸、间苯二甲酸、1,2,4-苯三酸、1,3,5-苯三酸的加标回收率分别为98.39%,98.81%,98.66%,97.73%,98.93%,98.90%,98.25%,98.40%。相对标准偏差分别为0.87%,0.49%,0.76%,0.88%,0.71%,0.46%,0.63%,0.47%,方法的检出限分别为0.1,0.2,0.1,0.4,0.1,0.4,0.6,2.0mg/L,线性范围分别为0.88-17.50,1.48~29.60,1.47~29.30,1.34~26.80,1.79~35.80,2.70~53.90,2.98~59.50,3.00~59.90mg/L。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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