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Sodium Persulfate (sodium + persulfate)
Selected AbstractsGrafting emulsion polymerization of glycidyl methacrylate onto leather by chemical initiation systemsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008K. A. Shaffei Abstract The kinetics of the grafting polymerization of glycidyl methacrylate (GMA) onto leather were studied with chemical initiation systems. The results showed that the rate of grafting of GMA onto leather was dependent on different rates in the chemical initiation systems; for ammonium persulfate (AmPS)/acetone sodium bisulfite (ASBS), potassium persulfate (PPS)/ASBS, and sodium persulfate (SPS)/ASBS, the powers were 1.06, 0.48, and 0.43 and 0.63, 0.46, and 0.43, respectively, with respect to the concentration of the emulsifier sodium dodecyl sulfate, whereas the powers were 1.41, 0.70, and 0.81, respectively, with respect to the monomer concentration. The apparent activation energy was calculated for each initiation system and was found to be 180.8, 361.63, and 542.45 kcal for the AmPS/ASBS, PPS/ASBS, and SPS/ASBS systems, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Microemulsion polymerization of styrene stabilized by sodium dodecyl sulfate and short-chain alcoholsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 19 2001Chorng-Shyan Chern Abstract Styrene microemulsion polymerizations with different short-chain alcohols [n -CiH2i+1OH (CiOH), where i = 4, 5, or 6] as the cosurfactant were investigated. Sodium dodecyl sulfate and sodium persulfate (SPS) were used as the surfactant and initiator, respectively. The desorption of free radicals out of latex particles played an important role in the polymerization kinetics. An Arrhenius expression for the radical desorption rate coefficient was obtained from the polymerizations at temperatures of 50,70 °C. The polymerization kinetics were not very sensitive to the alkyl chain length of alcohols compared with the temperature effect. The maximal polymerization rate in decreasing order was C6OH > C4OH > C5OH. This was related to the differences in the water solubility of CiOH and the structure of the oil,water interface. The feasibility of using a water-insoluble dye to study the particle nucleation mechanisms was also evaluated. The parameters chosen for the study of the particle nucleation mechanisms include the cosurfactant type (CiOH), the SPS concentration, and the initiator type (oil-soluble 2,2,-azobisisobutyronitrile versus water-soluble SPS). © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3199,3210, 2001 [source] Determination of stable carbon isotopes of organic acids and carbonaceous aerosols in the atmosphereRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 15 2006R. Fisseha A wet oxidation method for the compound-specific determination of stable carbon isotopes (,13C) of organic acids in the gas and aerosol phase, as well as of water-soluble organic carbon (WSOC), is presented. Sampling of the organic acids was done using a wet effluent diffusion denuder/aerosol collector (WEDD/AC) coupled to an ion chromatography (IC) system. The method allows for compound-specific stable carbon isotope analysis by collecting different fractions of organic acids at the end of the IC system using a fraction collector. ,13C analyses of organic acids were conducted by oxidizing the organic acids with sodium persulfate at a temperature of 100°C and determining the ,13C value of the resulting carbon dioxide (CO2) with an isotope ratio mass spectrometer. In addition, analysis of ,13C of the WSOC was performed for particulate carbon collected on aerosol filters. The WSOC was extracted from the filters using ultrapure water (MQ water), and the dissolved organic carbon was oxidized to CO2 using the oxidation method. The wet oxidation method has an accuracy of 0.5, with a precision of ±0.4, and provides a quantitative result for organic carbon with a detection limit of 150,ng of carbon. Copyright © 2006 John Wiley & Sons, Ltd. [source] In situ chemical oxidation of residual LNAPL and dissolved-phase fuel hydrocarbons and chlorinated alkenes in groundwater using activated persulfate,REMEDIATION, Issue 2 2009Joan Siegal A treatablity study (TS) was conducted to evaluate the efficacy of in situ chemical oxidation (ISCO) using activated persulfate, alone and in combination with air sparging (AS), for treating a source area contaminated with residual light nonaqueous-phase liquid (LNAPL), dissolved-phase fuel hydrocarbons (HCs), and dissolved-phase chlorinated alkenes at Edwards Air Force Base (AFB), California. The TS was implemented in two phases. Phase I included injecting a solution of sodium persulfate and sodium hydroxide (NaOH) into groundwater via an existing well where residual LNAPL and dissolved-phase contaminants were present. Because the results of Phase I indicated a limited distribution of the activated persulfate, Phase II was performed to assess whether AS could enhance the distribution of the sodium persulfate. Each phase was followed by groundwater monitoring and sampling at the injection well and at three monitoring wells, located 20 to 44 feet from the injection well. Results from Phases I and II of the TS indicated that (1) alkaline-activated persulfate was effective in promoting the dissolution of LNAPL and the degradation of dissolved-phase contaminants, but only at the injection well; (2) the addition of AS was effective in enhancing the radius of persulfate distribution from less than 20 feet to greater than 44 feet, and (3) persulfate alone (i.e., not in an activated state) was effective in reducing the concentrations of dissolved-phase fuel HC and chlorinated alkenes. © 2009 Wiley Periodicals, Inc. [source] | ||||||||||