Pyrolysis temperature program

Figure 1 has shown that the maximum chemisorption of oxygen on chars from untreated wood occurs at HTT 450°-500°C. However, in order to understand better the effect of metal ions on the total process consisting of pyrolysis and subsequent chemisorption and oxidation of wood char, it was necessary to carry out pyrolysis, isothermal chemisorption and oxidation reactions in a single experiment. A typical overall pyrolysis, isothermal chemisorption (140°C) and oxidation curve is shown in Figure 2. The temperature program is (1) heat from 25° to 500°C at 5°C/min, (2) cool at...

Pyrolysis-Gas Chromatography-Mass Spectrometry. In the experiments, about 2 mg of sample was pyrolyzed at 900°C in flowing helium using a Chemical Data System (CDS) Platinum Coil Pyrolysis Probe controlled by a CDS Model 122 Pyroprobe in normal mode. Products were separated on a 12 meter fused capillary column with a cross-linked poly (dimethylsilicone) stationary phase. The GC column was temperature programmed from -50 to 300°C. Individual compounds were identified with a Hewlett Packard (HP) Model 5995C low resolution quadruple GC/MS System. Data acquisition and reduction were performed on the HP 100 E-series computer running revision E RTE-6/VM software. 

Temperature-programmed vacuum pyrolysis in combination with time-resolved soft ionization mass spectrometry allows principally to distinguish between two devolatilization steps of coal which are related to the mobile and non-mobile phase, respectively. The mass spectrometric detection of almost exclusively molecular ions of the thermally extracted or degraded coal products enables one to study the change of molecular weight distribution as a function of devolatilization temperature. Moreover, major coal components can be identified which are released at distinct temperature intervals. 

M. Brebu, M. Azhar Uddin, A. Muto, Y. Sakata, and C. Vasile, The role of temperature program and catalytic system on the quality of acryl-onitrile-butadiene-styrene degradation oil, /. Anal. Appl. Pyrolysis, 63 (l) 43-57, March 2002. 

Pyrolysis GC-MS Analysis. Flash pyrolysis was performed by using a pyroprobe 100 (Chemical Data Systems) temperature-control system. Samples were pyrolyzed from 150 to 750 °C with a temperature program of 20 °C/ms and a final hold for 20 s. After pyrolysis, the fragments were separated on a 25-m CP WAX 57 fused silica capillary column (temperature program 25-220 °C at 3 °C/min), followed by MS on a R 10-10 C (Ribermag, Rueil-Malmaison, France) operated at 70 eV and scanned from 20 to 400 m/z. 

Other approaches to boron nitride, by Paine, Paciorek, and Sneddon and their coworkers are shown in reaction sequences (16) and (17), processes that involve the loss of Me3Si, NH2, or Cl side units from borazine rings as pyrolysis proceeds in the temperature program leading up to 1,000 °C.61-63... 

L. Ballice, Classification of volatile products evolved during temperature-programmed co-pyrolysis of low-density polyethylene (LDPE) with polypropylene (PP). Fuel, 81(9),1233-1240 (2002). 

L. Ballice and R. Reimerta, Classification of volatile products from the temperature-programmed pyrolysis of polypropylene (PP), atactic-polypropylene (APP) and thermogravimetrically derived kinetics of pyrolysis. Chem. Eng. Process., 41(4), 289-296 (2002). 

McCoy, B. Distribution kinetics for temperature-programmed pyrolysis. Industrial and Engineering Chemistry Research 1999 38 4531. 

This mathematical model describing the inhomogeneous pyrolysis reactions by a set of apparent kinetic data (which are changing with the progress of the pyrolysis) should be understood as a first attempt to set up a mechanism to predict pyrolysis. The target of the application of this model would be to evaluate the influence of temperature programs on baking behavior. 

Carroll, B., and E. P. Manche Kinetic Parameters from Temperature-Programmed Reactions The Pyrolysis of Polytetrafluorethylene. J. Appl. Polymer Sci. 9, 1895 (1965). 

Figure 13. A plot of retention time against retention time for pyrolysis products on temperature programmed columns coated with OV-1 and OV-17 stationary phase, respectively [80]...

Physical and spectral properties of batrachotoxins are presented in Table I. Mass spectra have been presented and interpreted (3,13,14). The parent ion of batrachotoxin is virtually nondetectable by direct probe methods, and instead an apparent molecular ion of miz 399 is seen, probably because of pyrolytic elimination of the pyrrole carboxylate moiety. Batrachotoxin alkaloids do not chromatograph on capillary gas chromatographic columns, but a pyrolysis product has been detected at 280°C on the temperature-programmed, packed OV-1 columns used for analysis of other dendrobatid alkaloids (see Appendix). The pyrrole carboxylate moiety is responsible for major ions of C7H9N02 (m/z 139), C6H9N ... 

H. Sato, K. Kondo, S. Tsuge, H. Ohtani, and N. Sato, Mechanisms of thermal degradation of a polyester flame retarded with antimony oxide/brominated polycarbonate studied by temperature programmed analytical pyrolysis. Poly. Degr. Stab., 62, 41-48 (1998). 

Temperature-programmed pyrolysis A pyrolysis in which the sample is heated at a controlled rate over a range of temperatures during which pyrolysis occurs. 

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