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in subjects: "Alkylation"

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Studies of Coupled Chemical and Catalytic Coal Conversion Methods

The objective of this research was to convert coal into a soluble substance under mild conditions. The strategy involved two steps, first to breakdown the macromolecular network of coal, and second to add hydrogen catalytically. We investigated different basic reagents that could, in priciple, break down coal's structure and alkylation strategies that might enhance its solubility. We examined O- and C-alkylation, the importance of the strength of the base, the character of the added alkyl group… more

Date: December 1, 1991

Creator: Stock, L. M.; Chatterjee, K.; Cheng, C.; Ettinger, M.; Flores, F.; Jiralerspong, S. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Gaseous phase coal surface modification

In this report, we present an improved, feasible and potentially cost effective method of cleaning and beneficiating ultrafine coal. Increased mechanization of mining methods and the need towards depyritization, and demineralization have led to an increase in the quantity of coal fines generated in recent times. For example, the amount of {minus}100 mesh coal occurring in coal preparation plant feeds now typically varies from 5 to 25% of the total feed. Environmental constraints coupled with th… more

Date: May 7, 1992

Creator: Okoh, J.M.; Pinion, J. & Thiensatit, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Charge separation in photoredox reactions

This report deals with the photoreduction of alkylmethylviologens in vesicles in which the combined effect of the alkylmethylviologen chain length and the addition of cholesterol to the vesicle system has been assessed. Although the alkyl chain length effect predominately controls the photoreduction yield it is shown that cholesterol addition can tune the magnitude of this effect. A series of neutral alkylphenothiazines has been synthesized and the effect of alkyl chain length in variously char… more

Date: October 1, 1991

Creator: Kevan, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Superacid Catalyzed Coal Conversion Chemistry. Final Technical Report, September 1, 1983-September 1, 1986

This research project involved the study of a raw comparatively mild coal conversion process. The goal of the project was to study model systems to understand the basic chemistry involved and to provide a possible effective pretreatment of coal which significantly improves liquefaction-depolymerization under mild conditions. The conversion process operates at relatively low temperatues (170/sup 0/C) and pressures and uses an easily recyclable, stable superacid catalysts (HF-BF/sub 3/). It conse… more

Date: January 1, 1986

Creator: Olah, G.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Repair of DNA treated with. gamma. -irradiation and chemical carcinogens. Progress report, March 15, 1979-March 15, 1980

The identification and purification of 3-methyladenine glycosylase from the cell nuclei of rat liver was completed. The characterization of 7-methylguanine N-glycosylase activity in E. coli is currently under investigation. Alkylated DNA in chromatin structures as a substrate for 3-methyladenine N-glycosylase is discussed. An enzyme from E. coli and mammalian tissue active on 2,6-diamino-4-hydroxy-5-N-methyldormamido-pyrimide is isolated and characterized. Studies are proceeding on the correlat… more

Date: January 1, 1980

Creator: Goldthwait, D.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing low rank coals and low severity conditions (reaction temperatures generally less than 350{degrees}C) are the primary focus of the liquefaction experiments, as it is expected that the effec… more

Date: 1990-06~

Creator: Baldwin, R. M. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Catalysis-by-design impacts assessment

Catalyst researchers have always recognized the need to develop a detailed understanding of the mechanisms of catalytic processes, and have hoped that it would lead to developing a theoretical predictive base to guide the search for new catalysts. This understanding allows one to develop a set of hierarchical models, from fundamental atomic-level ab-initio models to detailed engineering simulations of reactor systems, to direct the search for optimized, efficient catalyst systems. During the la… more

Date: May 1, 1991

Creator: Fassbender, L L; Young, J K & Sen, R K

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the 12th and final quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The overall objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions… more

Date: 1991-09~

Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the fifth quarter of this contract dealing with applications of coal pretreatment techniques in coal hydroliquefaction by co-processing. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal conversion utilizing l… more

Date: 1989-12~

Creator: Baldwin, R. M. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

NMR spectroscopy and imaging of macerals in Argonne premium coals

Macerals that have been separated from two high-volatile bituminous coals from the Argonne Premium Coal Sample Program are surveyed using chemical and NMR spectroscopic techniques. Quantitative aspects of the method are discussed. Alkylation using {sup 13}C enriched methyl iodide followed by solid {sup 13}C NMR analysis was used to determine the concentrations of acidic OH and CH sites in these macerals. Also, the first successful application of nuclear magnetic resonance imaging (MRI) for spat… more

Date: January 1, 1990

Creator: Botto, R.E.; Choi, C.Y.; Dieckman, S.L.; Gopalsami, N.; Thompson, A.R. & Tsiao, C.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Zeolite catalysis: technology

Zeolites have been used as catalysts in industry since the early nineteen sixties. The great majority of commercial applications employ one of three zeolite types: zeolite Y; Mordenite; ZSM-5. By far the largest use of zeolites is in catalytic cracking, and to a lesser extent in hydrocracking. This paper reviews the rapid development of zeolite catalysis and its application in industries such as: the production of gasoline by catalytic cracking of petroleum; isomerization of C/sub 5/ and C/sub … more

Date: July 1, 1980

Creator: Heinemann, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

The findings in the first phase were as follows: 1. Both reductive (non-selective) alkylation and selective oxygen alkylation brought about an increase in liquefaction reactivity for both coals. 2. Selective oxygen alkylation is more effective in enhancing the reactivity of low rank coals. In the second phase of studies, the major findings were as follows: 1. Liquefaction reactivity increases with increasing level of alkylation for both hydroliquefaction and co-processing reaction conditions. 2… more

Date: December 1991

Creator: Baldwin, R. M. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Chemistry and morphology of coal liquefaction. Annual report, October 1, 1979-September 30, 1980

The present annual report summarizes quarterly reports and includes work performed during the last quarter of fiscal 1980. The first year of this project has just been completed and much of the time and effort has been concentrated on equipment building, assembling, testing, and on staffing. This, of course, has been more true in the areas of work with spectroscopic and high pressure equipment than in organic chemical reactions. More experimental results are therefore reported in the areas of h… more

Date: September 1, 1980

Creator: Heinemann, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Coal anion structure and chemistry of coal alkylation. Final report, March 1, 1979-February 29, 1980

In accord with Task 1, some ether cleavage reactions were carried out in two different media - potassium/naphthalene/tetrahydrofuran and potassium/ ammonia - so that the merits and demerits of the two methods could be compared. Preliminary results suggest that both systems yield the same products, and that the ammonia medium is more convenient to work with, because of the absence of by-products such as reduced naphthalenes and tetralin. Dialkyl ethers were found to be least reactive compounds w… more

Date: January 1, 1980

Creator: Stock, L.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Formation of gas-phase peroxides in a rural atmosphere: An interpretation of the recent SOS/SERON field results

Hydrogen perioxide (H{sub 2}O{sub 2}) and certain organic peroxides such as hydroxymethyl-hydroperoxide (HMHP), are gas-phase oxidants present in the atmosphere at ppbv concentration levels. These oxidants play an important role in atmospheric chemistry. In addition, precipitation containing H{sub 2}O{sub 2} is toxic to trees, and it has also been suggested that organic peroxides formed presumably by ozone reactions with biogenic alkenes are responsible for leaf disorders. Recently, we have dev… more

Date: September 1, 1993

Creator: Lee, J. H.; Tang, I. N. & Weinstein-Lloyd, J. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Sulfided heterogeneous, bimetallic RuMo catalysts derived from mixtures of Ru sub 3 (CO) sub 12 (or RuCl sub 3 ) and a molybdenum heteropolyanion. The reactions of ethanol with tetrahydroquinoline

Efforts have been made to develop Ru/Mo bimetallic catalyst systems for hydrodenitrogenation (HDN) of tetrahydroquinoline (THQ)- In the course of these studies, it was discovered that in ethanol, under H{sub 2} and in the presence Of CS2, Precatalyst solutions containing Ru (as Ru{sub 3} (CO){sub 12} or RuCl{sub 3}) and Mo (as the H{sub 3}PMO{sub 12}0{sub 40} heteropolyanion (HPA)) decompose to form bimetallic, sulfided particles. Particle diameters run from 0.1 to 5 {mu}m depending on the rate… more

Date: January 1, 1992

Creator: Koo, Sang-Man; Ryan, D. & Laine, R. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Studies of Coupled Chemical and Catalytic Coal Conversion Methods

More efficient coal conversion is being investigated based on the concept that catalytic dihydrogenation addition transformations of the coal molecule will be accelerated if the catalytic agents are covalently incorporated into the coal molecules such that there is an intimate relationship between the catalyst and the target molecule. Exploratory research is being conducted concerning such issues as catalyst selection, the discovery of suitable chemical procedures for the incorporation of the c… more

Date: January 1, 1988

Creator: Stock, L. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Sulfided heterogeneous, bimetallic RuMo catalysts derived from mixtures of Ru{sub 3}(CO){sub 12} (or RuCl{sub 3}) and a molybdenum heteropolyanion. The reactions of ethanol with tetrahydroquinoline

Efforts have been made to develop Ru/Mo bimetallic catalyst systems for hydrodenitrogenation (HDN) of tetrahydroquinoline (THQ)- In the course of these studies, it was discovered that in ethanol, under H{sub 2} and in the presence Of CS2, Precatalyst solutions containing Ru [as Ru{sub 3} (CO){sub 12} or RuCl{sub 3}] and Mo [as the H{sub 3}PMO{sub 12}0{sub 40} heteropolyanion (HPA)] decompose to form bimetallic, sulfided particles. Particle diameters run from 0.1 to 5 {mu}m depending on the rate… more

Date: September 1, 1992

Creator: Koo, Sang-Man; Ryan, D. & Laine, R. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advances in Process Intensification through Multifunctional Reactor Engineering

This project was designed to advance the art of process intensification leading to a new generation of multifunctional chemical reactors utilizing pulse flow. Experimental testing was performed in order to fully characterize the hydrodynamic operating regimes associated with pulse flow for implementation in commercial applications. Sandia National Laboratories (SNL) operated a pilot-scale multifunctional reactor experiment for operation with and investigation of pulse flow operation. Validation… more

Date: June 27, 2011

Creator: Timothy O’Hern, Lindsey Evans, Jim Miller, Marcia Cooper, John Torczynski, Donovan Pena, and Walt Gill, SNL, Will Groten, Arvids Judzis, Richard Foley, Larry Smith, and Will Cross, CR&L / CDTECH & T. Vogt, Lummus Technology / CDTECH.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Corrosion Behavior of Nickel Alloys in Wet Hydrofluoric Acid

Hydrofluoric acid is a water solution of hydrogen fluoride (HF). Hydrofluoric acid is used widely in diverse types of industrial applications; traditionally, it is used in pickling solutions in the metal industry, in the fabrication of chlorofluorocarbon compounds, as an alkylation agent for gasoline and as an etching agent in the industry of glass. In recent years, hydrofluoric acid has extensively been used in the manufacture of semiconductors and microelectronics during the wet chemical clea… more

Date: February 6, 2004

Creator: Rebak, R. B.

Item Type: Book

Partner: UNT Libraries Government Documents Department

open access

Raman Scattering Sensor for Control of the Acid Alkylation Process in Gasoline Production

Gasoline refineries utilize a process called acid alkylation to increase the octane rating of blended gasoline, and this is the single most expensive process in the refinery. For process efficiency and safety reasons, the sulfuric acid can only be used while it is in the concentration range of 98 to 86 %. The conventional technique to monitor the acid concentration is time consuming and is typically conducted only a few times per day. This results in running higher acid concentrations than they… more

Date: April 19, 2006

Creator: Uibel, Rory, H.; Smith, Lee M. & Benner, Robert, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Versatile assembly of p-carboxylatocalix[4]arene-O-alkyl ethers

Crystallisation of lower-rim tetra-O-alkylated p-carboxylatocalix[4]arenes from pyridine results in the formation of both bi-layer and pillar type supramolecular motifs. Full alkylation at the calixarene lower rim has significant influence over the supramolecular self-assembly motif, including preclusion of pyridine guest molecules from the calixarene cavity in the solid state.

Date: July 8, 2009

Creator: Kennedy, Stuart; Teat, Simon J. & Dalgarno, Scott J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Asymmetric Intramolecular Alkylation of Chiral Aromatic Imines via Catalytic C-H Bond Activation

The asymmetric intramolecular alkylation of chiral aromatic aldimines, in which differentially substituted alkenes are tethered meta to the imine, was investigated. High enantioselectivities were obtained for imines prepared from aminoindane derivatives, which function as directing groups for the rhodium-catalyzed C-H bond activation. Initial demonstration of catalytic asymmetric intramolecular alkylation also was achieved by employing a sterically hindered achiral imine substrate and catalytic… more

Date: April 16, 2007

Creator: Watzke, Anja; Wilson, Rebecca; O'Malley, Steven; Bergman, Robert & Ellman, Jonathan

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Asymmetric Synthesis of (-)-Incarvillateine Employing an Intramolecular Alkylation via Rh-Catalyzed Olefinic C-H Bond Activation

An asymmetric total synthesis of (-)-incarvillateine, a natural product having potent analgesic properties, has been achieved in 11 steps and 15.4% overall yield. The key step is a rhodium-catalyzed intramolecular alkylation of an olefinic C-H bond to set two stereocenters. Additionally, this transformation produces an exocyclic, tetrasubstituted alkene through which the bicyclic piperidine moiety can readily be accessed.

Date: February 18, 2008

Creator: Tsai, Andy; Bergman, Robert & Ellman, Jonathan

Item Type: Article

Partner: UNT Libraries Government Documents Department