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The research focuses on the critical review and prediction of flash points of high molecular weight compounds used mainly in the specialty chemical area. Thus far this area of high molecular weight specialty chemicals has not been thoroughly reviewed for flash point prediction; therefore critical review for accuracy of experimental values is difficult. Without critical review, the chance of hazards occurring in the processing and handling of these compounds increases. A reliable method for making predictions is important to efficiently review experimental values since duplicate experimentation can be time consuming and costly. The flash point is strongly correlated to the normal boiling point (NBP) but experimental NBP is not feasible for chemicals of high molecular weight. The reliability of existing NBP prediction methods was found inadequate for our compounds of interest therefore a new NBP prediction method was developed first. This method is based on ten simple group contributions and the molecular weight of the molecule. The training set included 196 high molecular weight C, H, N and O compounds. It produced an average absolute error (AAE) of 13K, superior to any other model tested so far. An accurate NBP is essential for critical review and new method development for flash point. A preliminary data analysis based on chemical family analysis allowed for detection of erroneous data points. These compounds were re-tested at a Huntsman facility. With a predicted normal boiling point, a new FP method that differentiates strong and iv weak hydrogen bonding compounds was developed. This was done because of the differences in entropy of vaporization for hydrogen bonding compounds. The training set consisted of 191 diverse C, H, N, O compounds ranging from 100 to 4000 g/mol in molecular weight. The test set consisted of 97 compounds of similar diversity. Both data sets produced an AAE of 5K and maximum deviation of 17.5K. It was also found that no substantial decomposition was found for these compounds at flash point conditions. These compounds appear to follow the same physical trends as lower molecular weight compounds. With this new method it is possible to critically review this class of chemicals as well as update NBP and other physical property data. / PDF file replaced 4-20-2012 at request of Thesis Office.

Accurate flash point and flammability limit data are needed to design safe chemical processes. Unfortunately, improper data storage and reporting policies that disregard the temperature dependence of the flammability limit and the fundamental relationship between the flash point and the lower flammability limit have resulted in compilations filled with erroneous values. To establish a database of consistent flammability data, critical analysis of reported data, experimental investigation of the temperature dependence of the lower flammability limit, and theoretical and empirical exploration of the relationship between flash points and temperature limits are undertaken. Lower flammability limit measurements in a 12-L ASHRAE style apparatus were performed at temperatures between 300 K and 500 K. Analysis of these measurements showed that the adiabatic flame temperature at the lower flammability limit is not constant as previously thought, rather decreases with increasing temperature. Consequently the well-known modified Burgess-Wheeler law underestimates the effect of initial temperature on the lower flammability limit. Flash point and lower temperature limit measurements indicate that the flash point is greater than the lower temperature limit, the difference increasing with increasing lower temperature limit. Flash point values determined in a Pensky-Martens apparatus typically exceed values determined using a small-scale apparatus above 350 K. Data stored in the DIPPR® 801 database and more than 3600 points found in the literature were critically reviewed and the most probable value recommended, creating a database of consistent flammability data. This dataset was then used to develop a method of estimating the lower flammability limit, including dependence on initial temperature, and the upper flammability limit. Three methods of estimating the flash point, with one based entirely on structural contributions, were also developed. The proposed lower flammability limit and flash point methods appear to predict close to, if not within, experimental error.

"The primary purpose of this research was to quantify fire suppression and fire intensification phenomena for water spray application to high flash point hydrocarbon oil pool fires. Test data and analyses of the phenomena include the drop size distribution and application and delivered densities of various water sprays, and spray-induced oil cooling and oil splattering for mineral seal oil and for cooking oil 30-cm diameter pool fires. Four different types of tests were conducted as described below. A Dantec Particle Dynamic, phase Doppler, Analyzer was used to measure the water drop sizes and velocities generated by 13 selected nozzles and sprinkler heads. Most measurements were made 0.91 m (3 ft) below the nozzles/sprinklers, since this was the location of the center of the hydrocarbon pool in later fire tests. The correlations for the volume-median drop diameter, dw, were of the form , where D is the nozzle orifice and is the spray Weber number based on D and the nozzle velocity. A ring burner was designed and constructed for uniformly heating oil pool surfaces from above and igniting them. The resulting oil temperatures while the oil was heated to its flash point satisfied the one-dimensional transient heat conduction model for a semi-infinitely thick solid with a shallow heated layer near the surface. Water sprays actuated when the oil surface temperature reached its flash point rapidly cooled the heated layer and caused mixing with the cooler oil below. Fire suppression tests were conducted to determine the relationship between required water spray density, drop size, and oil temperature in order to achieve suppression. A data correlation using non-dimensional parameters was developed to quantify the fire suppression criteria for the high flash point oil fires. Oil pool fires with the higher flash point oils, such as the 291oC flash point soybean oil, could be suppressed with much lower water densities than those of the lower flash point (137oC) mineral seal oil. However, if the water spray drop sizes are sufficiently small, the lower flash point oil fires can also be extinguished with lower spray densities. The NFPA 15 specified critical water density (0.30 gpm/ft2, 12 mm/min) to extinguish high flash point pool fires is only valid for mineral seal oil when the drop size is lower than about 300 µm. It is valid with larger drop sprays only when the flash point of the oil is higher than 190 according to the correlation developed here. Spray-induced pool fire intensification tests were conducted under a fire products calorimeter for measuring heat release rates. Supplemental oil vaporization rate tests were also conducted to determine the contributions of oil vaporization and oil splattering to the intensified fire. Results showed that vaporization could only account for between 1% and 1.7% of the heat release rate in intensified mineral seal oil fires, and less than 1% of the heat release rate in intensified soybean oil fires. The remainder is due to spray-induced oil splattering, which increased with increasing drop Weber number as well as increased oil temperature. The heat release rate is enhanced by factor from 2.12 to 5.55 compared to the heat release rate of free burning cooking oil. For mineral seal oil, this ratio is in the range 0.92 to 1.25 for the spray conditions tested. Correlations with the dimensionless factors of and the Weber number of the water spray were also developed to quantify the ratio of the splattered oil to applied spray density."

Incorporating consideration for safety issues while designing solvent processes has become crucial in light of the chemical process incidents involving solvents that have taken place in recent years. The implementation of inherently safer design concepts is considered beneficial to avoid hazards during early stages of design. The application of existing process design and modeling techniques that aid the concepts of ‘substitution’, ‘intensification’ and ‘attenuation’ has been shown in this work. For ‘substitution’, computer aided molecular design (CAMD) technique has been applied to select inherently safer solvents for a solvent operation. For ‘intensification’ and ‘attenuation’, consequence models and regulatory guidance from EPA RMP have been integrated into process simulation. Combining existing techniques provides a design team with a higher level of information to make decisions based on process safety. CAMD is a methodology used for designing compounds with desired target properties. An important aspect of this methodology concerns the prediction of properties given the structure of the molecule. This work also investigates the applicability of Quantitative Structure Property Relationship (QSPR) and topological indices to CAMD. The evaluation was based on models developed to predict flash point properties of different classes of solvents. Multiple linear regression and neural network analysis were used to develop QSPR models, but there are certain limitations associated with using QSPR in CAMD which have been discussed and need further work. Practical application of molecular design and process design techniques have been demonstrated in a case study on liquid-liquid extraction of acetic acid-water mixture. Suitable inherently safer solvents were identified using ICAS-ProCAMD, and consequence models were integrated into Aspen Plus simulator using a calculator sheet. Upon integrating flammable and toxic hazard modeling, solvents such as 5-nonanone, 2-nonanone and 5-methyl-2-hexanone provide inherently safer options, while conventionally-used solvent, ethyl acetate, provides higher degree of separation capability. A conclusive decision regarding feasible solvents and operating conditions would depend on design requirements, regulatory guidance, and safety criteria specified for the process. Inherent safety has always been an important consideration to be implemented during early design steps, and this research presents a methodology to incorporate the principles and obtain inherently safer alternatives.

Thesis (Ph. D.)--Worcester Polytechnic Institute. / Keywords: suppression; drop size; high flash point pool fire. Includes bibliographical references (p. 210-218).

Orientador: Maria Regina Wolf Maciel / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-12T16:55:11Z (GMT). No. of bitstreams: 1 Fregolente_LeonardoVasconcelos_D.pdf: 1867297 bytes, checksum: 6a22c8c7c525474c0864d4df237dce16 (MD5) Previous issue date: 2009 / Resumo: Neste trabalho, a técnica de planejamento de experimentos foi aplicada em diferentes estudos de otimização realizados na Refinaria de Paulínia (Replan). O trabalho abrange aplicações da técnica em escala laboratorial, em ferramenta computacional, até a utilização da técnica em diferentes plantas industriais. Os estudos de laboratórios consistiram na avaliação da dependência da lubricidade do diesel metropolitano em relação à sua composição e no desenvolvimento de uma nova metodologia para determinação do ponto de fulgor de frações leves de petróleo. Através de planejamentos fatoriais aplicados a um simulador do processo de coqueamento retardado (denominado DC-SIM), foram geradas equações polinomiais simples para a previsão de rendimentos dos produtos da unidade em sua etapa reacional. Utilizando estas equações, curvas de nível foram obtidas, as quais auxiliam na análise do comportamento da unidade frente a modificações nas condições de operação. Duas aplicações consistiram na realização de testes em plantas industriais. Primeiramente, utilizando planejamentos em dois níveis, foram levantados novos modelos para o controle avançado de uma torre de fracionamento de naftas através da realização de testes de identificação utilizando perturbações em degrau. A metodologia de planejamento de experimentos possibilitou uma análise multivariável do sistema. Finalmente, foram realizados experimentos seguindo planejamentos com configuração estrela para a maximização da recuperação de moléculas na faixa de destilação do GLP nas áreas de fracionamento de gases das duas unidades de coqueamento retardado da Replan. Por se tratar da maior refinaria de petróleo do país, sendo responsável por cerca de 20% da capacidade de refino no Brasil, a utilização de planejamentos fatoriais foi de fundamental importância para a viabilização de alguns testes em planta, já que reduz significativamente o número de experimentos necessários quando comparada à metodologia de avaliação de um fator por vez. Desta forma, o impacto dos testes na produção de derivados foi minimizado. Além disso, os resultados obtidos propiciaram um ganho econômico expressivo para a refinaria. / Abstract: In this work, experimental design technique was applied to different optimization studies, which were carried out in the Paulínia Refinery (Replan). The work covers applications of the technique in laboratorial scale, in computational tool, and the use of the technique in different industrial plants. The laboratory studies consisted in the evaluation of the dependence of the metropolitan diesel oil lubricity in relation to its composition and in the development of a new methodology to determine the flash point of light fractions of petroleum. Through factorial designs applied to a delayed coke simulator (named DC-SIM), simple polynomial equations were generated to predict the products yields of the unit in the reaction step. Using these equations, contour plots were obtained, which helped the analysis of the process response due to changes in the operating conditions. Two applications were done in industrial plants. First, using two level factorial designs, new models were adjusted to be used in the advanced control of a naphtha fractionation tower. The identification tests were carried out giving step disturbance in the manipulated variables. The experimental design methodology allowed a multivariable analysis of the system. Finally, experiments were done according to star configuration factorial designs in order to maximize the recovery of LPG molecules in the gases fractionating units of two delayed coke plants of Replan. Since Replan is the biggest oil refinery in Brazil, responsible for 20% of the national refining capacity, the use of factorial designs had a fundamental importance to allow the running of some tests in the plant. It reduces significantly the number of experiments, when it is compared to univariate methodology. Therefore, the impact of the tests in the production was minimized. Furthermore, the results provided very expressive financial earns / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

Orientador: Matthieu Tubino / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T09:33:03Z (GMT). No. of bitstreams: 1 Silveira_EvaLuciaCardoso_D.pdf: 1544784 bytes, checksum: 21e0e9cae43209115424068ca5568476 (MD5) Previous issue date: 2012 / Resumo: Um método de baixo custo é proposto neste trabalho para a análise quantitativa do álcool residual em biodiesel através da determinação do ponto de fulgor. Foram analisados ésteres metílicos obtidos de óleos de soja, milho, girassol e de sebo bovino. Os ésteres etílicos foram obtidos de óleo de soja. Em todos os casos ficou evidente que há uma correlação entre o ponto de fulgor e o teor de álcool residual no biodiesel. Assim, o parâmetro ponto de fulgor pode ser usado diretamente para determinar o teor de álcool residual do biodiesel. Foi proposto também um método para a determinação de fósforo em biodiesel por espectrofotometria de absorção molecular UV-Vis. As amostras de biodiesel são mineralizadas por calcinação a 550 °C seguindo dissolução do resíduo em H2SO4 1,0 mol L. O procedimento analítico é baseado na formação do complexo azul de molibdênio. Empregou-se o ácido 1-amino-2-naftol-4-sulfônico como agente redutor. O método foi aplicado para amostras de biodiesel de soja, canola, girassol e de sebo bovino. Os limites de detecção e quantificação obtidos para fósforo foram de 0,57 mg kg e 1,71 mg kg, respectivamente. O desvio padrão relativo médio obtido foi cerca de 5 %. A simplicidade do procedimento adicionado à precisão, exatidão e o baixo custo indicam que é uma excelente opção para a determinação de fósforo em biodiesel. Um terceiro método, neste caso, para a determinação de ânions em biodiesel baseado na extração com água assistida por ultrassom também foi desenvolvido neste trabalho. Os extratos obtidos das amostras de biodiesel foram analisados por cromatografia de íons. Os limites de quantificação foram 0,97; 4,10; 0,30; 2,47 e 0,26 mg kg para acetato, formiato, cloreto, fosfato e sulfato, respectivamente. A técnica de cromatografia de íons mostrou-se viável para a separação e quantificação de ânions orgânicos e inorgânicos em biodiesel simultaneamente diminuindo assim o tempo de análise / Abstract: A low cost method is proposed in this work for the quantitative analysis of residual alcohol in biodiesel through determination of the flash point. We analyzed methyl esters obtained from oils such as soy, corn, sunflower and of bovine fat. The ethyl esters were obtained from soy oil. In all cases it became very evident that there is a correlation between the flash point and the residual alcohol content in the biodiesel. Therefore the parameter flash point can be used to directly determine the residual alcohol content of biodiesel. A method has been proposed for the determination of phosphorus in biodiesel by UV-vis molecular absorption spectrophotometry. The biodiesel samples are mineralized using an ashing procedure at 550 °C following dissolution of the residue in 1.0 mol L H2SO4. The analytical procedure is based on the formation of a blue molybdenum complex. 1-amino-2naphthol-4-sulfonic acid is used as reducing agent. The method was applied to biodiesel samples of soy, canola and sunflower oils and of bovine fat. The limits of detection and quantification are 0.57 mg kg and 1.71 mg kg, respectively. The average standard deviation obtained was about 5 %. The simplicity of the procedure added to its precision, accuracy and low cost indicate that it is an excellent option for the determination of phosphorus in biodiesel. A third method, in this case, for the determination of anions in biodiesel based on extraction with ultrasound assisted water has also been developed in this study. The extracts of biodiesel samples were analyzed by ion chromatography. The limits of quantification obtained were 0.97, 4.10, 0.30, 2.47 and 0.26 mg kg for acetate, formate, chloride, phosphate and sulfate, respectively. The technique of ion chromatography proved to be feasible for the simultaneously separation and quantification of organic anions in biodiesel, thereby reducing analysis time / Doutorado / Quimica Analitica / Doutora em Ciências

Orientador: Matthieu Tubino / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T17:49:21Z (GMT). No. of bitstreams: 1 Mattos_RodrigoAlvesde_D.pdf: 2518556 bytes, checksum: a8c7635c9785df284e4cea0c8053443c (MD5) Previous issue date: 2012 / Resumo: O presente trabalho foi realizado usando biodieseis preparados a partir de óleos de soja, canola, milho, girassol e, também, de gordura suína, através de reações transesterificação. Para todos esses biodieseis foram determinados o ponto de entupimento a frio, o ponto de fulgor e o perfil cromatográfico. Estes biodieseis foram misturados com diesel de petróleo para se produzir misturas contendo 5% do biocombustível (B5), 10% (B10) e 20% (B20), e os ensaios citados foram realizados nestas amostras. Visando a diminuição do ponto de entupimento a frio, alguns aditivos naturais foram testados e se mostraram eficientes. Por exemplo, o limoneno reduziu o ponto de entupimento do biodiesel de óleo soja em mais de 7°C. No biodiesel de gordura suína a redução foi de 10°C, o que significa o ponto de entupimento a frio em temperatura inferior a 13°C. Os aditivos utilizados são solúveis nos biodieseis estudados e, também, nas misturas diesel-biodiesel, pelo menos nas concentrações testadas. Como importante exemplo de abaixamento do ponto de entupimento a frio das misturas diesel-biodiesel de gordura suína com 10% de biodiesel (B10), podese citar o caso da terebentina que provocou uma redução de aproximadamente 8°C (de 12,7ºC para 5,0°C). Este mesmo aditivo caus ou uma redução de 13,6 ºC (de 20,3ºC para 6,7ºC), na mistura diesel-biodiesel de gordura suína com 20% de biodiesel (B20). Este resultado é muito significativo por implicar na possibilidade de usar este tipo de combustível mesmo em regiões mais ao sul do país durante o inverno / Abstract: The present studies were performed preparing biodiesel from soya, canola, corn, sunflower oils and the fat swine, through transesterification reaction. The biodiesel produced from these oils were studied for: cold filter plugging point, flash point and for chromatographic analysis. The biodiesels were mixed with diesel to produce blends containing 5% of the biofuel (B5), 10% (B10) and 20% (B20), and these samples were also analyzed by the same techniques as discussed earlier. In order to decrease the cold filter plugging point, some natural additives have been tested and were proved effectively. For example, limonene caused more than 7°C reduction in the cold filter plugging point of soybean biodiesel. In the biodiesel obtained from the swine fats, the reduction was found around 10°C and less than 13°C for the cold filter plugging point. The additives are soluble in studied biodiesels and also in the dieselbiodiesel blends, at least, in the concentrations tested. One of the important example of the reduction in the cold filter plugging point of diesel-biodiesel blends of swine fats with 10% biodiesel (B10), using turpentine as additive which caused reduction of approximately 8°C (from 12,7ºC up to 5,0°C). The same additive caused a reduction of 13,6 ºC (from 20.3 ºC up to 6.7 °C) in the cold filter plugging point of diesel -biodiesel blends of swine fats with 20% biodiesel (B20). This result is very significant because it is possible to use this type of fuel in south regions of the country during the winter / Doutorado / Quimica Analitica / Doutor em Ciências

<p>  This dissertation focuses on the examination of the influence of sample storage conditions on the accuracy and precision of hydrocarbon composition measurements of Jet A made with GC×GC/FID and the accuracy and precision of flash point measurements of Jet A made with a Tag closed cup flash point tester. Areas of focus also include the influence of the column load value used, the S/N threshold value used, and the number of measurements made for a single sample vial on the accuracy and precision of the GC×GC/FID results. This dissertation also describes the development of an analytical method for the identification and quantitation of alkylphenols in Jet A (which are the most abundant heteroatom containing compounds in jet fuel) by using preparative high-performance liquid chromatography (prep-HPLC) and two-dimensional gas chromatography with electron ionization time-of-flight mass spectrometry (GC×GC/(+)EI TOF MS).</p>