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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The photochemical decomposition of acetone at low pressures.

Leach, Robert Orland January 1953 (has links)
No description available.
22

Azeotropic behavior in the critical region: the system acetone--n-pentane /

Cherry, Robert Homer January 1966 (has links)
No description available.
23

Equilibrium constants for the reaction of ethylenediamines with acetone and isobutyraldehyde : rate constants for the catalysis of the deduteration of isobutyraldeyde-2-ḏ by ethylenediamines /

Narducy, Kenneth Wayne January 1971 (has links)
No description available.
24

The solubility of mercury in polar gases /

Rosenberg, Harvey Sanford January 1973 (has links)
No description available.
25

AIminium ion formation and deuterium exchange by acetone in the presence of secondary amines and analogous hydrazine and hydroxylamine derivatives /

Evangelista, Ramon Acantilado January 1978 (has links)
No description available.
26

Application of Solar Energy to the Solvent Reclamation Industry

Litka, Arthur H. 01 January 1976 (has links) (PDF)
An analysis of an operational industrial acetone reclamation system is performed to ascertain the possibility of its adaptation of solar thermal energy augmentation using fixed orientation, flat plate solar collectors. Currently, the system utilizes and oil fired heater for the thermal input. The water is heated to 185°F (85°C) and circulated through a heat exchanger which is immersed within the contaminated acetone solution. The solvent is thereby vaporized, condensed, and drawn off for reuse. Analytical models of two possible configurations utilizing a series of commercially available, flat plate solar collectors, a hot water storage tank, and an oil fired auxiliary are developed. The resulting differential equation is written in finite difference form and integrated with an iterative numerical algorithm. Program listings are included for the solution of this problem on a Texas Instruments, SR-56 programmable calculator. Results of the analysis indicate that annual fuel savings of between 11 and 31 percent can be realized (compared to present non-solar operation) by the use of 6 to 16 collectors respectively. Based on an "ideal" day's performance, an economic analysis is given which recommends the use of 16 collectors for the present system. At current fuel, equipment, and fuel cost increase rates, the rate of return attained from the system retro-fit investment is commensurate with that available under a low risk savings investment. Therefore, an economic justification for conversion of the system to solar energy is marginal under the present conditions. A sensitivity analysis is included that indicates the conditions necessary for economic justification. Specifically, if the current collector cost was reduced by 65 percent, the solar system configuration would yield an acceptable rate of return on the investment.
27

Application of Sputtering Technology on Preparing Visible-light Nano-sized Photocatalysts for the Decomposition of Acetone

Wu, Yi-chen 05 September 2007 (has links)
This study investigated the decomposition efficiency of acetone using unmodified (pure TiO2) and modified TiO2 (TiO2/ITO¡BTiO2/N) prepared by sputtering technology. The influence of operating parameters including wavelength and relative humidity on the decomposition efficiency of acetone was further discussed. Operating parameters investigated included light wavelength (350~400, 435~500, and 506~600 nm), photocatalysts (TiO2/ITO, TiO2/N, and TiO2), and relative humidity (RH) (0%, 50%, and 100%). In the experiments, acetone was degraded by photocatalysts in a self-designed batch photocatalytical reactor. Samples coated with TiO2 were placed in the batch reactor. The incident light with different wavelength was irradiated by a 20-watt lamp. Moreover, a low-pressure mercury lamp for UV light or LED lamps for blue and green lights were placed on the top of reactor. Acetone was injected into reactor by using a gasket syringe. Reactants and products were analyzed quantitatively by a gas chromatography with a flame ionization detector followed by a methaneizer (GC/FID-Methaneizer). The structure of the photocatalyst film surface showed taper and the width of column ranged from 100 to 200 nm. The film structure showed crystallization cylindrical surface and the thickness of the photocatalyst film was in the range of 4.0-4.3 £gm. The highest decomposition efficiency of acetone was observed by using TiO2/ITO under visible-light with 50% RH. The synthesis of TiO2 was mainly anatase for the tested photocatalysts. AFM images showed that the photocatalyst surface appeared rugged and the shape showed a mountain ridge distribution . Keywords: sputtering technology, modified photocatalysts, photosensitive, acetone, photocatalytic oxidation, acetone decomposition
28

Fundamental factors affecting the extraction efficiency in a pulse liquid-liquid extractor.

Swisher, George Thomas, January 1954 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1954. / Typewritten. Vita. Bibliography: leaves 191-199. Also available via the Internet.
29

Transformation of Acetone and Isopropanol to Hydrocarbons using HZSM-5 Catalyst

Taco Vasquez, Sebastian 2009 December 1900 (has links)
This research describes the production of hydrocarbons from acetone and isopropanol produced by the MixAlco process. The MixAlco process has two types of products: acetone and isopropanol. The effect of the temperature, weight hourly space velocity (WHSV), type of catalyst, feed composition, and pressure are studied. For the isopropanol reaction, the following conditions were used: HZSM-5 (280), 1 atm, 300–410°C, and 0.5–11.5 h–1, respectively. The temperature and WHSV affect the average carbon number of the reaction products. A product similar to commercial gasoline was obtained at T = 320 °C and WHSV= 1.3 to 2.7 h–1. Also, at these conditions, the amount of light hydrocarbons (C1–C4) is low. For the acetone reaction, the following conditions were used: HZSM-5 with silica alumina ratio (Si/Al) 80 and 280 mol silica/mol alumina, 1–7.8 atm, 305–415°C, 1.3–11.8 h–1, and hydrogen acetone ratio 0–1 mol H2 /mol acetone. The conversion on HZSM-5 (80) was higher than HZSM-5 (280); however, for HZM–5 (80) the production of light hydrocarbons (C1–C4) was more abundant than (280), and it formed less coke. For acetone, the effect of high pressure (P = 7.8 atm) was evaluated. At high pressure, the conversion was lower than at atmospheric pressure. HZSM-5 (280) rapidly deactivated, and the amount of light hydrocarbons (C1–C4) increased. For acetone, co-feeding hydrogen inhibited coke formation and decreased the amount of light hydrocarbons (C1–C4).
30

Feasibility study of photocatalysis on the volatile organic compounds using TiO2 coated activated carbon fiber

Wu, Yu-jiuan 06 September 2005 (has links)
This study combined photocatalytic technology with activated carbon adsorption to decompose gaseous pollutants. Gaseous pollutants were initially adsorbed and concentrated by activated carbon and could be further decomposed more effectively by photocatalytic technology. This study coated TiO2 on the activated carbon fiber (ACF) by a sol-gel process for conducting the adsorption and decomposition of acetone in a batch reactor. Operating parameters investigated in this study included the initial concentration of acetone (13.6 £gM and 27.2 £gM), reaction temperature (50¢J~70¢J), oxygen concentration (0.5%~20%), and water vapor (0 £gM~244.9 £gM). The incident UV light of 365 nm was irradiated by a 15-watt low-pressure mercury lamp placing above the photocatalytic batch reactor. The ACF coated with TiO2 was placed in the center of the reactor. Acetone was injected into the reactor to conduct photocatalytic tests. Reactants and products were analyzed quantitatively by a gas chromatography with electron capture detector (GC/ECD) and a flame ionization detector followed by a methaneizer (GC/FID-Methaneizer). Results from the photocatalysis tests indicated that, among the commercial TiO2 (Degussa P-25), NO3-/TiO2 and SO42-/TiO2, SO42-/TiO2 had the best photoactivity reduced acetone concentration and reaction time substantially. The end products was mainly CO2 and CO, which resulted in the mineralization ratio above 95%. Results from the operating parameter tests revealed that the increase of the initial acetone concentration enhanced the amount of acetone adsorbed on the ACF, which however did not increase the reaction rate of acetone. Although the increase of reaction temperature could reduce the amount of acetone adsorbed on the ACF, decomposition rate of acetone could be promoted, so as the yield rate and mineralization ratio of products (CO2 and CO). Increasing oxygen concentration did not influence the decomposition significantly except for oxygen concentration lower than 1%. The increase of water vapor would slightly decrease the amount of acetone adsorbed on the ACF, which did not decrease the decomposition of acetone anyway. This study revealed that the decomposition of acetone on TiO2/ACF can enhance the mass transfer of acetone substantially.

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