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The results of a study on the parametric sensitivity of acetic acid production by hydrolysis of acetic anhydride, using acid homogeneous catalysis in a batch reactor, are presented. Dimensionless parameters of mass and energy balances...

The classical design of continuous chemical reactors exploits steady-state operation, which is optimized and maintained by appropriate control systems. Nevertheless, it is well-known that the reactor performance can be enhanced by applying periodic regimes, like forced modulations of input parameters.The identification and evaluation of suitable periodic operation conditions is challenging. One approach that can be used is based on nonlinear frequency response (NFR) analysis. The focus of this work is the experimental analysis of shapes for two simultaneously imposed modulations (sinusoidal and square) in comparison to results predicted by the NFR method. The acetic anhydride hydrolysis was studied in an adiabatic CSTR exploiting a periodic operation mode, which was found to be superior to the corresponding steady-state operation.

The classical design of continuous chemical reactors exploits steady-state operation, which is optimized and maintained by appropriate control systems. Nevertheless, it is well-known that the reactor performance can be enhanced by applying periodic regimes, like forced modulations of input parameters.The identification and evaluation of suitable periodic operation conditions is challenging. One approach that can be used is based on nonlinear frequency response (NFR) analysis. The focus of this work is the experimental analysis of shapes for two simultaneously imposed modulations (sinusoidal and square) in comparison to results predicted by the NFR method. The acetic anhydride hydrolysis was studied in an adiabatic CSTR exploiting a periodic operation mode, which was found to be superior to the corresponding steady-state operation.

The classical design of continuous chemical reactors exploits steady-state operation, which is optimized and maintained by appropriate control systems. Nevertheless, it is well-known that the reactor performance can be enhanced by applying periodic regimes, like forced modulations of input parameters.The identification and evaluation of suitable periodic operation conditions is challenging. One approach that can be used is based on nonlinear frequency response (NFR) analysis. The focus of this work is the experimental analysis of shapes for two simultaneously imposed modulations (sinusoidal and square) in comparison to results predicted by the NFR method. The acetic anhydride hydrolysis was studied in an adiabatic CSTR exploiting a periodic operation mode, which was found to be superior to the corresponding steady-state operation.

The classical design of continuous chemical reactors exploits steady-state operation, which is optimized and maintained by appropriate control systems. Nevertheless, it is well-known that the reactor performance can be enhanced by applying periodic regimes, like forced modulations of input parameters.The identification and evaluation of suitable periodic operation conditions is challenging. One approach that can be used is based on nonlinear frequency response (NFR) analysis. The focus of this work is the experimental analysis of shapes for two simultaneously imposed modulations (sinusoidal and square) in comparison to results predicted by the NFR method. The acetic anhydride hydrolysis was studied in an adiabatic CSTR exploiting a periodic operation mode, which was found to be superior to the corresponding steady-state operation.

A new chemo-enzymatic treatment is proposed to produce cellulosic fibers suitable for heterogeneous- or homogeneous-phase acetylation. The procedure included enzymatic (laccase–violuric acid) lignin removal from the precursor fibers (unbleached sulfite pulp) followed by hydrogen peroxide treatment. An optional intermediate stage included partial hydrolysis (endoglucanase) to increase fiber reactivity. The obtained ‘‘biobleached’’ fibers were acetylated in the heterogeneous phase with acetic anhydride in nonpolar solvents, yielding various acetyl group contents, depending on the severity of the reaction. The degree of acetylation was highly sensitive to the treatment conditions, mainly the acetic anhydride activity in the system. The results were compared to those obtained after acetylation of commercial, dissolving-grade fibers, used as reference. The effect of the inherent nature of the fibers tested were elucidated as far as hemicellulose content, fiber length, fine content and crystallinity. Acetyl group content of up to 24% were determined after heterogeneous reaction with the chemoenzymatic fibers. The substitution of hydroxyl groups by acetyl moieties resulted in a lower hydrophilicity, as assessed by measurement of the water contact angle. Homogeneous acetylation of the chemo-enzymatic and reference fibers resulted in relatively similar acetyl group content (up to 36 and 33%, respectively). These samples were soluble in acetone and produced transparent films (via solvent casting), with enhanced dry strength and lower hydrophilicity. Overall, it is concluded that the proposed chemo-enzymatic treatment is a feasible alternative for the production of fibers that are suitable for efficient acetylation, Postprint (author's final draft)

Present study tackles theoretical analysis and mathematical modeling of the process of homogeneous first-order reaction in the cascade of perfect mixing reactors of continuous action (PMR-C). The modeling of chemical reactors is based on the thermal and material balances in combination with chemical kinetics. The mathematical model of the dynamics of the process of homogeneous first-order reaction in the PMR-C cascade is represented in the form of equations of change in the molar fraction of substance over time and a change in the inner energy of the ideal flow of substance. In the present work, we calculated, by the mathematical model, the process of acetic anhydride hydrolysis in 5 sequentially connected PMR-C. Calculation by the model is performed by the Runge-Kutta method of third order. We obtained temperature profiles for the dynamics of the process of acetic anhydride hydrolysis for a cascade of PMR-C. The temperature gradient in reactor grows over time; consequently, it takes on a constant value. We analyzed the impact of the volume of reaction mixture on the depth of the course of the process both for the separate perfect mixing reactors and for the cascade of perfect mixing reactors. With an increase in the volume of mixture, the reaction rate increases, while the speed of reaching the necessary degree of conversion decreases. The speed of reaching the maximum degree of conversion for the cascade of reactors compared with one perfect mixing reactor of the same volume is considerably higher. Recommendations regarding the course of the process are formulated. We calculated the value of cost for conducting the process of acetic anhydride hydrolysis depending on the change in temperature. Minimum cost is attained at temperature 341 K and amounts to UAH 1.70 million per year., Математическая модель динамики процесса гомогенной реакции первого порядка в каскаде реакторов идеального смешения построена уравнением изменения мольной доли вещества со временем и изменением внутренней энергии идеального потока вещества. Расчет по модели осуществлено методом Рунге-Кута третьего порядка для реакции гидролиза уксусного ангидрида. Получены профили температур динамики процесса, рассчитан стоимостной показатель, Математична модель динаміки процесу гомогенної реакції першого порядку в каскаді реакторів ідеального змішування побудована рівнянням зміни мольної частки речовини з часом і зміною внутрішньої енергії ідеального потоку речовини. Розрахунок по моделі здійснено за методом Рунге-Кута третього порядку для реакції гідролізу оцтового ангідриду. Отримано профілі температур динаміки процесу, розраховано вартісний показник

The method of nonlinear frequency response (NFR) attempts to predict the outcome of perturbation for the instructive input variables using nonlinear functions within the model equations. The aim of the derived models is the estimation of optimal frequencies and amplitudes for sinusoidal changes of the total inlet flow, concentration, temperature and the cooling temperature, as well as combinations of several of these inputs. As a model reaction the hydrolysis of acetic anhydride in a continuously stirred tank reactor (CSTR) has been chosen. This exothermal reaction is investigated for the cases of separately and simultaneously modulated inlet concentrations and feed flow rates. For the experimental validation of predicted model-based results at first a verification and adjustment of the kinetic parameters is performed. Based on these results an optimal steady-state is calculated, which is used as an initial state of periodic operations. To estimate the performance of the reaction system mean values of the conversion of acetic anhydride and the yield of acetic acid are compared to the corresponding steady-state values of the reactor. Different forcing frequencies, input amplitudes and, for multiple input parameter, phase shift between them are investigated. The theoretical foundation as well as systematic exploration of the experimental possibilities will be presented.

The method of nonlinear frequency response (NFR) attempts to predict the outcome of perturbation for the instructive input variables using nonlinear functions within the model equations. The aim of the derived models is the estimation of optimal frequencies and amplitudes for sinusoidal changes of the total inlet flow, concentration, temperature and the cooling temperature, as well as combinations of several of these inputs. As a model reaction the hydrolysis of acetic anhydride in a continuously stirred tank reactor (CSTR) has been chosen. This exothermal reaction is investigated for the cases of separately and simultaneously modulated inlet concentrations and feed flow rates. For the experimental validation of predicted model-based results at first a verification and adjustment of the kinetic parameters is performed. Based on these results an optimal steady-state is calculated, which is used as an initial state of periodic operations. To estimate the performance of the reaction system mean values of the conversion of acetic anhydride and the yield of acetic acid are compared to the corresponding steady-state values of the reactor. Different forcing frequencies, input amplitudes and, for multiple input parameter, phase shift between them are investigated. The theoretical foundation as well as systematic exploration of the experimental possibilities will be presented.

The method of nonlinear frequency response (NFR) attempts to predict the outcome of perturbation for the instructive input variables using nonlinear functions within the model equations. The aim of the derived models is the estimation of optimal frequencies and amplitudes for sinusoidal changes of the total inlet flow, concentration, temperature and the cooling temperature, as well as combinations of several of these inputs. As a model reaction the hydrolysis of acetic anhydride in a continuously stirred tank reactor (CSTR) has been chosen. This exothermal reaction is investigated for the cases of separately and simultaneously modulated inlet concentrations and feed flow rates. For the experimental validation of predicted model-based results at first a verification and adjustment of the kinetic parameters is performed. Based on these results an optimal steady-state is calculated, which is used as an initial state of periodic operations. To estimate the performance of the reaction system mean values of the conversion of acetic anhydride and the yield of acetic acid are compared to the corresponding steady-state values of the reactor. Different forcing frequencies, input amplitudes and, for multiple input parameter, phase shift between them are investigated. The theoretical foundation as well as systematic exploration of the experimental possibilities will be presented.

The method of nonlinear frequency response (NFR) attempts to predict the outcome of perturbation for the instructive input variables using nonlinear functions within the model equations. The aim of the derived models is the estimation of optimal frequencies and amplitudes for sinusoidal changes of the total inlet flow, concentration, temperature and the cooling temperature, as well as combinations of several of these inputs. As a model reaction the hydrolysis of acetic anhydride in a continuously stirred tank reactor (CSTR) has been chosen. This exothermal reaction is investigated for the cases of separately and simultaneously modulated inlet concentrations and feed flow rates. For the experimental validation of predicted model-based results at first a verification and adjustment of the kinetic parameters is performed. Based on these results an optimal steady-state is calculated, which is used as an initial state of periodic operations. To estimate the performance of the reaction system mean values of the conversion of acetic anhydride and the yield of acetic acid are compared to the corresponding steady-state values of the reactor. Different forcing frequencies, input amplitudes and, for multiple input parameter, phase shift between them are investigated. The theoretical foundation as well as systematic exploration of the experimental possibilities will be presented.

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

This critical review focuses on potential routes for the multi-production of chemicals and fuels in the framework of thermochemical biorefineries. The up-to-date research and development in this field has been limited to BTL/G (biomass-to-liquids/gases) studies, where biomass-derived synthesis gas (syngas) is converted into a single product with/without the co-production of electricity and heat. Simultaneously, the interest on biorefineries is growing but mostly refers to the biochemical processing of biomass. However, thermochemical biorefineries (multi-product plants using thermo-chemical processing of biomass) are still the subject of few studies. This scarcity of studies could be attributed to the limitations of current designs of BTL/G for multi-production and the limited number of considered routes for syngas conversion. The use of a platform chemical (an intermediate) brings new opportunities to the design of process concepts, since unlike BTL/G processes they are not restricted to the conversion of syngas in a single-reaction system. Most of the routes presented here are based on old-fashioned and new routes for the processing of coal- and natural-gas-derived syngas, but they have been re-thought for the use of biomass and the multi-production plants (thermochemical biorefinery). The considered platform chemicals are methanol, DME, and ethanol, which are the common products from syngas in BTL/G studies. Important keys are given for the integration of reviewed routes into the design of thermochemical biorefineries, in particular for the selection of the mix of co-products, as well as for the sustainability (co-feeding, CO2 capture, and negative emissions).

Organosilicon-mediated, regioselective acetylation of vicinal- and 1,3-diols is presented. Methyl trimethoxysilane or dimethyl dimethoxysilane was first used to form cyclic 1,3,2-dioxasilolane or 1,3,2-dioxasilinane intermediates, and subsequent acetate-catalyzed monoacylation was efficiently performed by addition of acetic anhydride or acetyl chloride under mild conditions. The reaction exhibited high regioselectivity, resulting in the same protection pattern as in organotin-mediated schemes., QC 20120803

Homogeneous Fenton reaction (H2O2/Fe2+ system) using significantly substoichiometric concentrations of H2O2 oxidant to oxidize phenol was characterized focusing on the formation of stable aromatic intermediates. Beyond the most abundant benzenediols, the pattern of aromatic intermediates was chiefly characterized by hydroxylated biphenyls and diphenyl ethers with different degrees of hydroxylation. Hydroxylated dibenzofurans (DBF), p,p'-dioxins, as well as highly condensed aromatic intermediates including polyols of polycyclic aromatic hydrocarbons (PAHs), could also be detected, but in lower concentrations. The formation of aromatic intermediates could be predicted on the basis of oxidative coupling reactions of resonance-stabilized radicals generated by the attack of the highly reactive hydroxyl radicals (OH*) on phenol. GC/MS identification of oxidative coupling intermediates was performed after derivatization of the solvent extracts. Derivatization reactions included silylation to give TMS (trimethylsilyl) ethers, as well as single-step extractive acetylation using acetic anhydride in alkaline aqueous solutions (pH 10.5) to give acetates. Solvent extraction of aqueous solutions, a prerequisite to generate TMS ethers, caused strong discrimination of polyols due to their low distribution coefficients in non-polar solvents. This discrimination could be overcome by extracting the in-situ formed acetates of the intermediates. Extractive acetylation allowed the detection of tri-, tetra-, and pentahydroxylated aromatic intermediates generated by Fenton oxidation processes, which have been overlooked up to now. Thus, extractive acetylation to detect stable aromatic intermediates covering a wide range of hydroxylation degrees can foster the understanding, monitoring, and management of advanced oxidation processes, especially in the field of wastewater treatment.

Chinese culture plays a major role in the formation of China's policies regarding its exportation of illicit drugs and precursor chemicals. China is a major producer of illicit drugs and precursor chemicals. The trafficking of illicit drugs is a transnational crime that affects the United States, China, and ultimately the world. The Chinese have been slow to cooperate with U.S. law enforcement officers regarding the trafficking of these drugs/chemicals that include acetic anhydride, ephedrine/pseudoephedrine, and steroids. To better understand China's lack of cooperation with U.S. law enforcement agencies, one must look at Chinese culture to better understand the foundation of their policies. There are numerous variables one can consider in determining how China formulates its policies. Confucianism, the "Century of Shame," and Mao Zedong have been extremely influential in laying the groundwork for Chinese policy decision making. In addition to cultural influences, corruption's role in China's relations with U.S. law enforcement authorities must be addressed. Recognizing the cultural elements within China helps drug law enforcement investigators understand China's reluctance to cooperate with the United States in efforts to combat transnational drug trafficking that originates in China. The author concludes that understanding Chinese culture and the corruption operating there give U.S. law enforcement agencies a better understanding of Chinese reactions to requests for cooperation. It might also assist the United States in devising policies to circumvent any initial Chinese resistance. Overall, enlightened U.S. law enforcement officials may experience better cooperation and more success in their attempts to stymie the illicit Chinese chemicals entering the United States.

The enthalpy, or heat of reaction, for the hydrolysis of munitions grade VX in aqueous sodium hydroxide at 90 degrees C was determined in a 2-L Mettler RC1 Reaction Calorimeter. Typically, VX with dicyclohexylcarbodiimide (DCCDI) as a stabilizer was added to the sodium hydroxide solution in the reactor at 11.35 g/min. The average normalized enthalpy for nine reactions was -139.6 kJ (SN-1 4.2)/mol VX. The overall heat transfer coefficient of the final reaction mass was 178.3 (W/(m2 degrees K)) SN-1 7.7, and the specific heat capacity was 3.6 (kJ/(kg K)) SN-1 0.2. The thermodynamic quantities were not significantly different than previous reported data.

This report documents the construction and operation of Holston Ordnance Works, now known as the Holston Army Ammunition Plant (Holston AAP), Kingsport, Tennessee. The research was initiated by Geo-Marine, Inc. (GMI), in the spring and summer of 1995, and was continued by New South Associates in September and October of the same year. Holston Ordnance Works was a critically important installation in the Ordnance Department's government-owned contractor-operated (GOCO) industrial program during World War II. It contributed to the war effort by producing most of the explosive RDX and Composition B (a mixture of RDX and TNT) used by the Western Allies. These explosives went directly into the war effort and were vitally important to Allied victory in the Battle of the Atlantic. Later, they were used in the aerial war over both Germany and Japan. Due to the experimental and highly technical nature of the facility, Holston Ordnance Works was closely associated with its contractor, perhaps more so than most other Ordnance facilities. The operating contractor in this case was the Tennessee Eastman Corporation (TEC). Now known as the Eastman Chemical Company, TEC was then a subsidiary of the Eastman Kodak Company, based in Rochester, New York. Located in Kingsport long before the war, TEC was familiar with the manufacture of acetic acid and acetic anhydride, both essential to the making of RDX. This connection led to Kingsport as the site for Holston, with Tennessee Eastman selected to run it. Due to the unique nature of this facility, Holston was divided into two parts. Area A, close to the original TEC manufacturing plant, produced and refined the acetic acid and acetic anhydride needed for the production of RDX. These were then shipped over to Area B, a few miles away, where the RDX was manufactured and combined with TNT to form Composition B, the final product of the

The 4,6-dinitroso derivative was obtained (83%) by the nitrosation of 2-oxooctahydroimidazo imidazole as the dihydrochloride and was converted to the 4,6-dinitro derivative (66%) by treatment with nitric acid (100%, -40 C) and to the 1,4,6-trinitro derivative (66%) and the 1,3,4,6-tetranitro derivative (86%) by treatment with nitric acid (100%) in acetic anhydride at 0-5 C and 10-25 C respectively. Similar treatment with nitric acid (100%) in either acetic or trifluoroacetic anhydride at 0-25 C converted the trinitro compound to the tetranitro compound (86%). The dinitramine was also obtained (43%) from the diamine by nitration with nitric acid (100%, -40 C).

The Department of the Army and the General Services Administration have recommended that certain parcels of land located adjacent to the new acid area at Volunteer AAP be declared excess. Attempts were made to provide rationale for retention of this area based on the need for a safety buffer zone. This rationale was not accepted by DA since there is no formal policy in regard to buffer zones around areas containing bulk storage of common chemical compounds. This report describes the rationale and methodology used to establish hazard distances from which buffer zone policy can be established.

An interlaboratory study was conducted to compare two new hydroxyl equivalent weight methods. The methods tested were a toluenesulfonyl isocyanate procedure and a N-methyl-imidazole catalyzed acetic anhydride procedure. The statistical analysis of the data, interpretation of the results are discussed, as well as the problems encountered in running this type of study and suggestions are made for conducting future studies. Keywords: Hydroxyl; Equivalent weight; Methods; Interlaboratory study; Toluenesulfonyl; Isocyanate.

A number of substituted phenylacetylenes have been prepared as precursors to poly(phenylacetylenes) having regiospecific substitution. These latter were required for a study attempting to correlate structure with electronic properties, especially conductivity. The following phenylacetylenes were prepared: o-, m-, and p-nitrophenylacetylene, p-trifluoromethylphenylacetylene, o-and p-aminophenylacetylene (m-commercially available), o-, m-, and p-acetamido, and m- and p-trifluoroacetamidophenylacetylene. Starting materials were the appropriate nitro or trifluoromethyl cinnamic acids. Bromination followed by dehydrobromination and decarboxylation gave the corresponding phenylacetylenes. The amino compounds were obtained by Zn/NH4OH reduction of the o- and p-nitrophenyl-acetylenes. Acylations were accomplished with acetic or trifluoroacetic anhydride. (Author), Presented at Mid-Atlantic Regional Meeting, Americal Chemical Society, White Haven, PA Apr 83.

A gas-to-gas heat exchanger was installed to recover a portion of the heat from the ketene vapor stream leaving a cracking furnace to preheat the combustion air. Results of the evaluation indicated that combustion air temperature increases an average of 344 C. The final temperature of the ketene gas leaving the heat exchanger averaged 467 C and never dropped to the critical 350 C temperature at which recombination of the ketene/water and conversion to acetic acid occurs. There was no significant fouling inside the heat exchanger tube bundle and the rate and quality of crude acetic anhydride production were not affected. The amount of combustion air supplied to the furnace burners was about half the theoretical amount because of the draft air introduced to the furnace. Economic evaluation shows that the profitability index and payback period at the current production level is insufficient to justify the expense of installing the heat recovery systems on all the ketene cracking furnaces., Project engineer: S. Moy.

Three new procedures were developed for preparing HMX from hexamine, one involving TAT as the intermediate; the others, DADN and DANNO. The DADN process was studied in some detail; the other two were not developed beyond the exploratory stage. Overall yield (hexamine to HMX) in the DADN process is about 13% higher than that of the conventional Bachmann process, and the acetic anhydride requirement is considerably lower. The first two steps were demonstrated in continuous pilot plant operation, yielding about 14 lb/hour of DADN in simple equipment. Application of the inert carrier concept (ICP) did not show promise. A cost study indicated that the DADN process offered no advantage over the Bachmann, mainly because two additional acids (sulfuric and polyphosphoric) are used.

3-Chloro-2-hydroxy-1-propyl acetate, obtained from acetic acid and epichlorohydrin, was converted to its tetrahydropyranyl ether which was cyclized with base. Hydrolysis gave 3-hydroxyoxetane in 37% overall yield. This compound was converted to the tosylate, the bromide and the iodide, none of which underwent displacement by nitrite ion. The reaction of 3-oxetyl tosylate with potassium azide gave 3-azidooxetane which on hydrogenation gave 3-aminooxetne, also obtained from the tosylate and ammonia. Oxidation of the amine with m-chloroperbenzoic acid gave 3-nitrooxetane. Fluoronitromalonate esters were hydrolyzed to fluoronitroacetates, which, with formaldehyde gave the 2-fluoro-3-hydroxy-2-nitropropionates. The hydroxyls were protected as the tetrahydropyranyl ethers. Base hydrolysis of the ester groups followed by acid hydrolysis of the tetrahydropyranyl groups gave 2-fluoro-2-nitroethanol. Subsequently a one step synthesis of this compound from diethyl fluoronitromalonate, potassium carbonate and formaldehyde was developed. 1-Fluoro-1-nitroethylene was prepared by reactions of 2-fluoro-2-nitroethanol with acetic anhydride and potassium acetate, wth phthalic anhydride and also with dicyclohexyl carbodiimide. 2-Fluoro-2,2-dinitroethyl glycidyl ether was polymerized with triflic acid, triflic acid hydrates and triflic anhydride to give polymers with molecular weights up to 1800. NMR evidence indicated that triflate esters were intermediates. (Author)

The excited electronic states of biacetyl (CH3COCOCH3) have engaged the attention of many researchers over the past forty years. Interest has centered primarily on the lowest excited singlet state and the nearby triplet state lying slightly lower in energy. Early work involving biacetyl concentrated on the lifetime, yield, and quenching rates associated with the phosphorescence from triplet state molecules both in solution and in the vapor phase. Subsequent interest in biacetyl was related to its use as a gas phase emission standard and as a triplet energy acceptor in the study of triplet molecule participation in the photochemistry of other molecules. The literature on these aspects of the study of biacetyl has been extensively reviewed. More recent work involving biacetyl has used the behavior of this molecule to test theories of 'radiationless transitions'.

This report provides a summary review and evaluation of phytotoxicological literature of 11 compounds associated with U.S. Army Ammunition Plants. These compounds are: sulfur dioxide, ammonia, acetic acid and acetic anhydride, nitrous oxide, nitric oxide and nitrogen dioxide, methyl nitrate, nitromethane, tetranitromethane and the mononitrotoluenes. The estimated ambient concentrations for sulfur dioxide, acetic acid and nitrogen dioxide would not appear to pose a phytotoxic hazard. Because of lack of data, no conclusive statements can be made for the remaining compounds. Recommendations for further work on these latter compounds have been made; a protocol for ascertaining the phytotoxicity of airborne environmental contaminants has also been described in an appendix to the report. (Author)

Air used to supply oxygen to the fluomine bed of a model Open Loop Oxygen Generating System (OLOGS) was adulterated with various contaminants to study their effect on performance of the fluomine chemical and purity of the oxygen product. Contaminants investigated were water, carbon dioxide, carbon monoxide, benzene, n-heptane, ethanol, acetone, acetaldehyde, Freon 12, and nitrogen dioxide. No deleterious effect on fluomine chemical was observed at the contaminant concentration used during short-term testing. Oxygen purity was affected to various extent by the different contaminants. Carbon monoxide, carbon dioxide, and nitrogen dioxide did not accumulate in the oxygen product. Water concentrated to 5%. The organic contaminants accumulated up to 8 times their concentration in the supply air. Nitrogen dioxide was the only contaminant irreversibly absorbed by the fluomine. Odor was present in the oxygen product when odorous organic contaminants were present in the supply air. The authors concluded that the fluomine beds need protection from excessive water, N-oxide and organic contamination to avoid oxygen of unacceptable quality and possible accelerated fluomine degradation.

HMX is obtained in substantially increased amount by means of novel modification of the conventional process for producing HMX by reaction of hexamine with a nitrating agent consisting of HNO3-NH4NO3 solution in acetic acid-acetic anhydride medium, wherein the nitrating agent, hexamine solution and acetic anhydride are concurrently added to a mixture of acetic acid and acetic anhydride called a 'heel'. The modification involves incorporating a small amount of hexamine in the heel prior to the addition of a major portion of the nitrating agent. (Author), Supersedes PAT-APPL-734 685-76.

Recycle of spent acid in nitrolysis of hexamine to RDX is accomplished under conditions, which avoid or minimize the need to process the spent acid through conventional costly recovery operations and result in little, if any, reduction of RDX yield. The conditions include (a) effecting the simmering in spent acid containing between 0% and 2% water; (b) recycling at least part of the spent acid of 0-2% water content to dissolve the hexamine reactant; and (c) preferably also recycling a part of the spent acid, after elimination of any water contained therein with acetic anhydride, to the heel to which the reactants are added in the nitrolysis of hexamine to RDX. (Author), Supersedes PAT-APPL-900 212-78.

Most hydroxyl equivalent weight analyses call for relatively large prepolymer samples which may be impractical when dealing with small research products. The following describes a semi-micro procedure using an acetic anhydride/N-methylimidazole (AA/NMIN) esterification. The semi-micro procedure when compared to the macro version had more scatter but accuracy was not significantly affected. The AA/NMIM method requires a polar solvent system which is necessary to form an ion intermediate, hence esterification of nonpolar prepolymers cannot be accomplished. Also presented is a semi-micro technique for determining the hydroxyl equivalent weight of nonhydrogen bonding prepolymers by measuring the free hydroxyl infrared absorbance. When the technique was compared to titrimetric methods, the differences were no greater than 6%. (Author)

The chemistry of the 2,6-diazabicyclooctane ring system was studied toward the synthesis of tetra- and hexa-substituted derivatives. Stable dinitro derivatives were prepared but attempts to prepare tetranitro derivatives by oxidative nitration were unsuccessful, and work on the diazabicyclooctanes was terminated. Methylenedinitramine (MEDINA) was successfully condensed with glyoxal in acetic anhydride to give a substitute dinitroimidazolidine which shows promise as a precursor for the synthesis of bicyclo HMX. Trichloroacetamidine condensed with glyoxal and oxalyl chloride to give a trichloromethyl substituted dihydroxyimidazoline and imidazolinedione respectively. The imidazoline was unstable and could not be converted into the bistrichloromethyl substituted tetraazabicyclooctane ring system for further condensation with trichloroacetamidine. The stable imidazolinedione, on the other hand, is a potential intermediate for such a condensation reaction. Trihalomethyl-bisformamides and bisacetamides are also potential precursors for this substituted bicyclic ring system. The trihalomethyl groups should precursors for this substituted bicyclic ring system. The trihalomethyl groups should stabilize the ring during nitrolysis reactions leading to the bicyclo-HMX system.

During the past decade a number of portable vapor detection systems have been developed in response to military and law enforcement problems. The report concerns efforts to evaluate the capabilities of certain of the most promising of these detection systems. The following detection systems have been examined: (1) Ion Mobility Spectrometer (a type of plasma chromatograph), Franklin Institute Research Laboratories; (2) Bioluminescent Sensor System, RPC Corporation; (3) Portable Quadrupole Mass Spectrometer, Varian Associates; (4) Model 27 Gelignite Detector and Model 58 Explosive Detector, Ion Track Instruments; (5) Explosive Detection Dogs, trained by Southwest Research Institute. Emphasis is on sensitivity and specificity. The compounds selected for sensitivity studies were ethylene glycol dinitrate (EGDN), trinitrotoluene (TNT), acetic anhydride, and cocaine.

A convenient and rapid procedure is described for determining the haze-foming tendency of woodpulp after acetylation and the amount of insoluble residue in the acetate solution. The method prescribes (1) a pretreatment that involves steeping the sample in water if it is air-dry, followed by steeping t in 85% acetic acid t room temperature, (2) displacement of the dilute acetic acid with glacial acetic acid, () acetylation with a mixture of glacial ACETICACID, ACETIC ANHYRIDE, AND SULFURIC ACID CATALYST, AND (4) measurement of haze and insoluble residue in the acetate solution before and after centrifuging. Approximately 5 hours are required for acetylation and measurement of haze. For a commercial softwood sulfite plp of acetylating grade, the initial haze was 1.6 to 3.0% and the insoluble residue was 0.13 to 0. 32%; after centrifuging, the haze was 1.6 to 2.0%.

Ultramicro procedures for the determination of serum cholesterol and of serum, plasma, or whole blood glucose are described. The chromogenic reaction of cholesterol with ferric iron was adapted to an ultramicro method. The results obtained with this procedure are compared to those obtained with a macro analysis which applies the chromogenic reaction of cholesterol with acetic anhydride and sulfuric acid in the presence of p-toluene sulfonic acid. Statistical evaluations of the method to determine reproducibility and variance are presented. The reliability of this methodin the presence of elevated serum bilirubin has been verified. One determination done in duplicate requires 20 microlitersl of serum. The color reaction obtained when glucose reacts with Beta-glucose oxidase in the presence of peroxidase and o-anisidine was evaluated for ultramicro analysis. The results obtained are compared with those given by the Technicon AutoAnalyzer procedure which utilizes the reduction of ferricyanide by glucose. Statistical evaluation of the precision of the method and variance analysis are presented, and the precautions necessary for reliable determination of glucose are emphasized. One determination done in duplicate requires 10 microloters of whole blood, serum, or plasma., ADA383786 ADA383788 ADA383789

The report describes research on the preparation and the study of nitroso and dinitroso fluorine aliphatic compounds using NO and NOCl over FeCl3. The reactions studied involved CF2 = CFCl, dechlorination of CF2Cl-CFClNo, CF2 = CF2 CF3CF = CF2, CF3COONO, CF3CF2COONO, CF3CO-O-COCF3.

Olefins containing a vinylic chlorine as CF2=CFCl, CF2=CCl2, CFCl-CFCl were irradiated in the presence of NO to form nitroso compounds. The photochemical reaction of perfluoroolefins with NO were studied when NO2 was absent and then in the presence of chlorine. The study of the reaction of CF3COOH and C3F7COOH and their anhydrides with NO and NOCl.

The reductive coupling of several nitrobenzenes by zinc/sodium hydroxide followed by acetylation of the resulting hydrazobenzenes with pyridine/acetic anhydride produced n-acetylhydrazobenzenes. Treatment of the n-acetylhydrazobenzenes with concentrated hydrochloric acid produced a series of n-acetylalkylbenzidines. These were further acetylated with pyridine/acetic anhydride to produce N,N'-diacetylalkylbenzidines. The infrared, ultraviolet, nuclear magnetic resonance and mass spectral properties of these materials were determined. (Author)

The invention describes a non-toxic cream having a specified chemical component which reacts exothermally upon the addition of water to provide heat for warming inanimate articles or living bodies subject to a cold environment such as immersion in water and the like. The chemical heat generating component includes alloys of lithium and aluminum, lithium and magnesium, aluminum and magnesium or powdered magnesium. The cream is spread directly upon the object to be warmed where environmental water initiates the warming reaction or the cream may be placed within a protective suit such as that worn by a diver or flyer with water admitted in controlled amounts to create the heat producing exothermic reaction.

A series of polynitrophenyl acetates have been prepared by reacting the parent phenol with acetic anhydride in carbon tetrochloride solution. Addition of pyridine catalysed most of the reactions, but pyridine salts were obtained from the trinitrophenols. Considerable variation in rates of the uncatalysed reactions has been observed. (Author)

Further attempts were made to replace the acidic hydrogen of the terminal acetylene groups of the acrylate monomers using propargyl acrylate as the key reactant. High dilution techniques and various reaction solvents were to be used in order to ascertain the feasibility of replacing the acidic hydrogen with various other groups. Due to the appearance of a number of articles dealing with the addition of decaborane to acetylenic bonds, it was decided to further explore this phase of the project. Efforts would be made to repeat some of the syntheses reported in these articles in order to apply the described techniques to this project, and to develop techniques applicable to the purification of a polymer containing the carborane nucleus. Also, an attempt would be made to prepare 1-acryloxy, 1-ethynyl cyclohexane, a new moner containing a terminal acetylene group. (Author)

Emphasis was placed upon the preparation of bromine-substituted polyphenyls and various intermediates as well as new methods of synthesis of this general class of compounds. Physical properties such as spectra (IR and UV) and melting points were determined. In the course of the research, a new and interesting reaction was explored: the catalytic dehydration of carbonylcontaining-compounds in the vapor phase over alumina. Also a preliminary report is made on a method for the separation and determination of purity of variou polyphenyl-type compounds. This method depends upon the solubility behavior of a substance as temperature and solvent composition are simultaneously changed. (Author)

The report describes research on the following studies: Adaptation of a solvent system for the reaction of CF2=CF2 and NOCl; The photochemical reaction of perfluoroacetic anhydride and NOCl, CF3COOH and NOCl, the decomposition of C2F5COONO, and fluoroolefins with NO or NOCl.