Small range 文档类型:"1"

Totally found 79 items.

  • [会议] CPVC反应单元工艺安全性分析
    研究了CPVC装置配料氯化反应单元所采取的工艺安全技术措施,也指出了一些不足,并提出了改进方向,PVC与稀盐酸在配料釜混合,用氮气压送至氯化反应釜进行通氯反应,加入分散剂和引发剂BPO,反应过程产生质量分数约6%的盐酸和CPVC,未反应的氯气送尾气塔用氢氧化钠吸收,反应后悬浮液再用氮气压送至中和釜,分析了配料和氯化反应单元配套环保单元缺陷及改进。
    关键词: 氯化聚乙烯;氯化反应;安全性分析;技术改造
  • [会议] Chlorinated phenol removal from aqueous media by tea (Camellia sinensis) leaf waste tailored activated carbon
    In this study, activated carbons (ACs) wereprepared from tea leaves by using a two-stage self-generated atmosphere method. The process was done by semi-carbonizing the precursor at 300 °C for 1 h, followed by the impregnation of the resulting char at 85 °C for 4 h and finally activation at 500 °C for 2 h. The semi-carbonised samples were impregnated with different ratios of zinc chloride (ZnCl2) and their physicochemical effect was studied. The prepared ACs underwent several aspects of both, chemical and physical characterizations, such as the percentage of yield, moisture content, ash content, pH, porosity, adsorption capacity of 2,4-dichlorophenol (2,4-DCP), surface area, porosity, morphology and surface chemistry studies. It was found that sample AC2, with an impregnation ratio of 2:1 was the best AC produced in this study. The maximum Brunauer, Emmett and Teller surface area of AC2 was found to be 695 m2/g. Langmuir, Freundlich and Temkin isotherm models were used to examine the experimental isotherms while the kinetic data was analyzed using the pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models. The 2,4-DCP adsorption isotherm results complied well to the Langmuir isotherm for the equilibrium data while the adsorption kinetic data fitted well to the pseudo-second order model, indicating that chemisorption by valency forces via the sharing (covalent bond) or exchanging of electrons between the AC and the 2,4-DCP molecules were mainly responsible for the adsorption process. From these findings, it is concluded that tea leaves can be used as a low cost precursor for the removal of 2,4-DCP in aqueous medium. Swaminathan G and Ramanujam T K 1999 Bioprocess Eng.21 169 Nowicki P, Kazmierczak J and Robert P 2015 Powder Technol.269 312 Joseph C G, Bono A, Anisuzzaman S M and Krishnaiah D 2014 J. Appl. Sci.14 3182 Krishnaiah D, Anisuzzaman S M, Bono A and Sarbatly R 2013 J. King Saud Univ. Sci25 251 Anisuzzaman S M, Joseph C G, Daud W M A W, Krishnaiah D and Yee H S 2015 Int. J. Ind. Chem6 9 Anisuzzaman S M, Joseph C G, Krishnaiah D, Bono A and Ooi L C 2015 Parametric and adsorption kinetic studies of methylene blue removal from textile simulated sample using Durian (DuriozibethinusMurray) skin Manuscript accepted in the journal of Water Sci. Technol. Anisuzzaman S M, Joseph C G, Taufiq-Yap Y H, Krishnaiah D and Tay V V 2015 J. King Saud Univ. Sci. (in press) Daud W M A W and Houshamnd A H 2010 J. Nat. Gas. Chem.19 267 Alicia Peláez-Cid A. and Margarita Teutli-León M.M. 2012 ed Virginia Hernández Montoya Dr. (InTech) Lignocellulosic Precursors Used in the Elaboration of Activated Carbon, Lignocellulosic Precursors Used in the Synthesis of Activated Carbon - Characterization Techniques and Applications in the Wastewater Treatment Özhan A, Ömer S, Küçük M M and Cafer S 2014 Cellulose.21 2457 Virginia Hernández-Montoya and Adrian Bonilla-Petriciolet 2012, 1stCroatia Vol. 1 Joseph C G and Yii F 2008 J. Eng. Sci. Technol.3 234 Kim J W, Sohn M H, Kim D S, Sohn S M and Kwon Y S 2001 J. Hazard. Mater.85 301 Karen J S, Greisly D M and Puello J 2014 Chem.Eng. Transactions.37 721 Tan I A W, Ahmad A L and Hameed B H 2008 J. Hazard. Mater154 337-346 Bulut Y and Aydın H 2006 Desalination.194 259 Gupta V K, Agarwal S. and Saleh T.A. 2011 J. Hazard. Mater.185 17 Gupta V K and Nayak A 2012 Chem. Eng. J.180 81 Hameed B H and Ahmad A A 2009 J. Hazard. Mater.164 870 Hartono S B, Ismadji S, Sudaryanto Y and Irawaty W 2005 J. Ind. Eng. Chem.11 864 Mittal A, Kaur D, Malviya A, Mittal J and Gupta V K 2009 J. Colloid. Interf.Sci.337 345 Tham Y J, Latif P A, Abdullah A M, Shamala-Devi A and Taufiq-Yap Y H 2011 Bioresources Technol.102 724 Al-Qodah Z and Shawabkah R 2009 Braz. J. Chem. Eng.26 127 Gundogdu A, Duran C, Senturk H B, Soylak M, Ozdes D, Serencam H and Imamoglu M 2012 J. Chem. Eng. Data.57 2733 Ahmaruzzaman M and Laxmi G S 2010 J. Chem. Eng. Data.55 4614 Graham H N 1992 Prev.Med.21 334 Wankhade A A and Ganvir V N 2013 Int.Res. J. Environment Sci.2 53 Kennedy L J, Vijaya J J, Kayalvizhi K and Sekaran G 2007 Chem. Eng. J.132 279 Sahu J N, Acharya J and Meikap B C 2010 Bioresource Technol.101 1974
    关键词: activated carbon;adsorption;chemical engineering;industrial waste;organic compounds;surface chemistry;zinc compounds
  • [会议] Can or cannot green rust reduce chlorinated ethenes?
    Green rusts(GRs)are Fe2+,Fe3+ layered double hydroxides that are widely investigated for the reduction of inorganic and organic pollutants in soils and groundwaters.Of particular interest is the use of GRs for the reduction of chlorinated ethenes,but existing literature shows contrasting results.Here,we tested 4 GRs(with different interlayer and hydroxide sheet modifications)in reactions with 3 different chlorinated ethenes(tetra-,tri-,and cis-dichloroethylene)for up to 10 months.Our results show that none of the freshly synthesized and untreated GRs can reduce the here tested chlorinated ethenes to any significant extent,corroborated by the lack of degradation products after 10 months and the absence of any significant volatilization.This is in stark contrast to previous literature,which reported that GR can degrade these chlorinated ethenes.The absence of reaction in our experiments is explained by having equilibrated GR suspensions,where the affinity of chlorinated ethenes for GR surfaces is extremely low.
    关键词: green rust;chlorianted solvents;remediation
  • [会议] Extent of natural attenuation of chlorinated ethenes at a contaminated site in Denmark
    Chlorinated solvents contaminated soils and aquifers are a widespread problem in industrialized countries and many require clean-up due to the risk of contaminant flow into groundwater systems.Clean-up is costly and often invasive,thus there is high interest in stimulating natural attenuation processes.For this,first an assessment of the type and extent of natural attenuation present at the site is required.Here,we present chemical,isotopic and microbial analyses of waters collected at a chlorinated ethene contaminated site in Denmark to give insights into natural attenuation processes.The data gives indication of complete reductive dechlorination by microbial communities but their extent varies greatly across short distances and between the different geological layers.The data further indicates that overall,chlorinated ethene degradation through natural attenuation is small at this site but near surface degradation due to aerobic co-metabolism or abiotic geochemical reduction could potentially play a role.
    关键词: Chlorinated solvents;remediation;compound stable isotope analysis;~(13)C
  • [会议] Theoretical studies on the electron transport property of chlorinated pentacenes derivatives
    To study the effect of chlorination on the charge-transport parameters of pentacene,a set of chlorinated pentacene derivatives(nCl-PENT-n)have been designed.And the geometries,electronic structures,reorganization energies,transfer integrals,and charge carrier transport parameters have been investigated with density functional theory(DFT)calculations and the inherent hopping model.For the designed molecules,with the increase of the chlorine number,the frontier molecular orbital energies decrease,which could improve air stability.Based on Marcus theory,the predicted hole mobilities(μh=0.46 cm2V-1s-1,μh,exp=0.2 cm2V-1s-1)and the electron mobilities(μe=0.61 cm2V-1s-1)values for6,13-dichloropentacene(DCP)crystal shows that DCP might be promising candidate as ambipolar OFET materials.Furthermore,μe of other chlorinated pentacene derivatives range from 2.47-9.01cm2V-1s-1 by means of the predicted crystal structures,which confirm that chlorination may be an effective method to design high performance n-type organic field-effect transistors.
    关键词: chlorinated;reorganization;frontier;hopping;orbital;inherent;chlorine;candidate
  • [会议] Determination of short-chain chlorinated paraffins(SCCPs) in fish using automated online GPC–GC–ENCI/MS combined with selective pressurized liquid extraction
    1.Introduction Short-chain chlorinated paraffins(SCCPs;C10–C13)[1,2],are currently being reviewed by the Stockholm Convention on Persistent Organic Pollutants for possible inclusion in their list of persistent organic pollutants(POPs)[3].In China,the annual production volumes of SCCPs have increased every year since the 1990s.However,
    关键词: chlorinated;SCCPs;GC;currently;inclusion;automated;persistent;POPs;detecting;hexane
  • [会议] City of Taylor Rehabilitates 60-Year-Old Cast Iron Mains via Pre-Chlorinated Pipe Bursting
    The city of Taylor, located in Wayne County, Michigan, serves a population north of 60,000 residents and, like many municipalities in the U.S. with aging and undersized infrastructure, they are experiencing systemic water system failures that require major system updates. For the city of Taylor, most of these recurring failures are happening in their residential neighborhood distribution piping, which consist of 60-year-old 6-inch cast iron water mains. The city with the help of their consultant, Wade Trim Engineering, decided that since the pipe issues were systemic and replacement of those water mains would require a larger diameter pipe, the preferred method of rehabilitation would be pre-chlorinated pipe bursting with the installation of an upsized 8-inch DR 18 fusible polyvinyl chloride pipe (FPVCP). This method meant less disruption to the homeowners' property, provided a discrete water shut-off and disruption schedule for homeowners, and kept the installation of the new main within road rights-of-way and existing easements. Since the start of the project in September 2016, Bidigare Contractors have installed over 35,000 feet of 8-inch DR 18 FPVCP and 1,000 feet of 12-inch DR 18 FPVCP. This paper will review the basic steps and process for the pre-chlorinated pipe bursting method being used in Taylor. It will also review the results of the project construction and the program in general.
    关键词: -
  • [会议] EFFECT OF AGING IN HOT CHLORINATED WATER ON THE MECHANICAL BEHAVIOR OF POLYPROPYLENE FOR SOLAR-THERMAL APPLICATIONS
    Polypropylene (PP) is increasingly considered as a material choice for pressurized components in solar-thermal systems. In these systems, the materials are exposed to superimposed mechanical and environmental loads. The objective of this research is the characterization of the mechanical behavior of three different black-pigmented polypropylene (PP) grades immersed for up to 750 h in chlorinated water (5 ppm chlorine content) at an elevated temperature of 60℃. Hence, values for strain-at-break and essential work of fracture were determined by tensile tests. For the strain-at-break values and for the essential work of fracture values a similar exposure dependence was obtained. Depending on the PP grade, time-to-embrittlement values of 250 h and 750 h were achieved. For one PP grade, both testing methods led to an identical timc-to-cmbrittlcmcnt value of 750 h.
    关键词: polypropylene;solar-thermal collector;chlorinated water;aging;mechanical properties
  • [会议] Determination of Chlorinated Polycyclic Aromatic Hydrocarbons in Sediments
    Polycyclic aromatic hydrocarbons have been ubiquitously distributed in environment. Chlorinated polycyclic aromatic hydrocarbons (CIPAHs) are compounds in which one to several hydrogen atoms of PAHs are substituted to chlorine atom. Some research has measured the concentration of CIPAHs in stack gas, fly ash and bottom ash collected from municipal and industrial waste incinerators and in environmental samples from e-waste recycling sites. Since CIPAHs has a large number of isomers, CIPAHs in the environment was not fully investigated. In this study, the concentrations of CIPAHs in sediments taken from Tokyo bay was determined by HRGC-HRMS to assess the pollution of CIPAHs in the aquatic environment. We found that a number of CIP AH isomers and highly chlorinated CIPAHs were observed in the sediment from Tokyo bay. In particular, higher concentrations of Cl_3Pyr and Cl_4Pyr were detected in the sediments compared to the concentrations of ClPyr and Cl_2Pyr. These results suggested that highly chlorinated PAHs were present in the aquatic environment and CIPAHs have a potential as persistent organic pollutants.
    关键词: -
  • [会议] Investigation of chlorinated modifier content influence on the physical-mechanical properties and vulcanizing characteristics of rubber and rubber mixture
    Present paper is devoted to the novel solution for the chlorination technology of polyolefin and diene rubbers - mechanochemical halide modification, as a more efficient way to obtain halogenated elastomers with a wide range of halogen content (from 3 to 7 %). The vulcanizing characteristics of elastomeric compounds based on the chlorinated rubber compounds as well as the production conditions of vulcanization process have been studied by the methods of dynamic mechanical rheometry. The performed investigation revealed the influence of chlorine content in different types of rubber compounds on rheological and physical-mechanical properties. New halogen-containing polyolefins rubbers produced by this technology proved themselves in the conditions of the rubber production.
    关键词: Rubber (major);Chlorination;Mechanical properties
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