摘要:
Producing carbon fiber precursors and carbonized fibers comprise by treating a thin film of catalytic pitch at elevated temperature conditions, treating the resulting heavy isotropic pitch by agitating with an inert gas under elevated temperature conditions to form a mesophase pitch, forming green fibers from said mesophase pitch, stabilizing and optionally carbonizing said green fibers to obtain the desired product.
摘要:
In addition to analysis in the infrared spectra of hydrocarbon group types, it has now been found that certain hydrocarbon species, including preferably aromatic species such as benzene, toluene, xylene, and alkyl benzenes such as ethyl benzene, can be determined by measuring absorption in certain selected wavelengths in the infrared spectra, then manipulating the data, e.g., preferably by taking the first or higher derivative, and applying statistical techniques, preferably multiple linear regression (MLR) to provide an output signal indicative of the concentration of the particular specie. The output signal can be used to control refinery and chemical processes, e.g., reforming, catalytic cracking, alkylation and isomerization. In manufacturing reformulated fuels, government regulations can be complied with by utilizing the invention to blend fuels which have a maximum of benzene or other regulated components.
摘要:
A monitoring of catalytic cracking processing is provided which uses near infrared (NIR) analysis to characterize cracking feeds, intermediates and products for chemical and physical properties such as saturates, monoaromatics, diaromatics, triaromatics, tetraaromatics, polar aromatics, total aromatics, thiophenes, distillation points, basic nitrogen, total nitrogen, API gravity, total sulfur, MCRT and % coker gasoil and the resulting characterization thereof. The NIR results can be used in FCC simulation software to predict unit yields and qualities.
摘要:
Reformulated gasoline (RFG) testing recently required by EPA involves measuring sulfur, olefin, aromatic contents, Reid Vapor Pressure (RVP), and benzene, distillation properties, plus total air pollutants (TAPs), volatile organic carbon (VOC), and nitrogen oxides (NOx). Measuring driveability, although not required, is desirable. All of these tests can be conducted by spectrometer, preferably in the IR range, more preferably in the NIR range, and most preferably by a single instrument operating at high-correlation wavelengths. Importantly, VOC, TAP, NOx, and RVP may be correlated to IR absorbance at certain bands. Statistical methods including PLS, MLR, PCR, and neural networks can be used and derivatives of first, particularly second, or other orders can be used. Results can be displayed on a single screen.
摘要:
A Fourier-Transform Raman spectrometer was used to collect the Raman spectra of (208) commercial petroleum fuels. The individual motor and research octane numbers (MON and RON, respectively) were determined experimentally using the industry standard ASTM knock engine method. Partial Least Squares (PLS) regression analysis can be used to build regression models which correlate the Raman spectra (175) of the fuels with the experimentally determined values for MON, RON, and pump octane number (the average of MON and RON) of the fuels. Each of the models was validated using leave-one-out validation. The standard errors of validation (SEV) are 0.415, 0.535, and 0.410 octane numbers for MON, RON, and pump octane number, respectively. By comparing the standard error of validation to the standard deviation for the experimentally determined octane numbers, it is evident that the accuracy of the Raman determined values is limited by the accuracy of the training set used in creating the models. The Raman regression models were used to predict the octane numbers for the fuels which were not used to build the models. The results compare favorably with the leave-one-out validation. Also, it is demonstrated that the experimentally determined Reid Vapor Pressures are highly correlated with the Raman spectra of the fuel samples and can be predicted with a standard error of 0.568 psi.
摘要:
Oxygenated hydrocarbons can be predicted within .+-.0.2% wt or better, using Raman NIR spectroscopy and multivariate analysis, with optional fiberoptics multistreaming. The resulting signal can be used to control concentration of such compounds in product to desired levels.
摘要:
Producing carbon fiber precursors and carbonized fibers comprise by treating a thin film of catalytic pitch at elevated temperature conditions, treating the resulting heavy isotropic pitch by agitating with an inert gas under elevated temperature conditions to form a mesophase pitch, forming green fibers from said mesophase pitch, stabilizing and optionally carbonizing said green fibers to obtain the desired product.