Linear-pyrolysis experiment

It can be calculated that the apparent activation energy during linear pyrolysis (as opposed to bulk degradation) would then be about 15 kcal./mole (see below). Thus, the value of 16 kcal./mole determined by Schultz and Dekker (85) and Coates (22) with their linear pyrolysis experiments agrees well with bulk degradation experiments. 

As thermal analysis has showed APP destabilizes nylon 6, since the thermal decomposition is observed at a temperature 70°C lower than that of the pure nylon 6 [141]. However, the Intumescent layer effectively protects the underlying polymer from the heat flux and therefore in the configuration of the "linear pyrolysis" experiments, the formulation nylon 6/APP (40%) decomposes more slowly than pure polymer [141]. These experiments prove the fire retardant action of the intumescent char. 

Calculation of the rate of decomposition in the solid phase shows that it is significant only when Te/f approaches Ts. Thus, Teff Ts, and the apparent activation energy during linear pyrolysis is half of that measured in bulk degradation experiments. This conclusion can also be inferred from the relations given in Ref. 35.]... 

Prior to this study, the C4-benzenes had not been evaluated as potential thermal maturity indicators. The C4-benzenes in Table 4 were identified in the WCSB oU and aU the Fort Worth Basin oils analyzed. The TeMB and MiPB ratios appear to be robust maturity indicators, increasing linearly with increase in TAS for the Fort Worth Basin hydrocarbons. This result corroborates observations from the oil cracking pyrolysis experiments. In general, the DEMB-2 ratio also increases with increase in thermal maturity, although one apparent outlier makes preliminary interpretation of the DMEB-2 data questionable. 

The temperature rise time (TRT), i.e. the time required for the pyrolyser temperature to be increased from its initial to the final temperature, can be chosen in the range from several milliseconds to several minutes. Simultaneously, the temperature time profile (TTP), representing temperature as a function of time for a particular pyrolysis experiment, may be easily programmable. Pyrolysis may be carried out at a fast rate of temperature increase, e.g. 10 000 K s i in the case of flash pyrolysis, or the sample can be heated at a controlled rate over a temperature range in which pyrolysis occurs using a stepwise, linear or ballistic heating approach characterized by a total heating time (THT) of several minutes or even hours. 

The experiment was carried out in a reaction cell shown in Fig. 3.3 with inner walls covered by a zinc oxide film having thickness 10 pm [20]. The surface area of the measuring film on the quartz plate was about 1/445 of the total film area on the wall of the vessel. The results of direct experimental measurements obtained when the adsorbent temperature was -196 C and temperature of pyrolysis filament (emitter of H-atoms) 1000°C and 1100°C, are shown on Fig. 3.4. One can see a satisfactory linear dependence between parameters A r (the change in film conductivity) and APh2 (reduction of hydrogen pressure due to adsorption of H-atoms), i.e. relations... 

The results of open-system pyrolysis (Rock-Eval II) have been used to specify the kinetic parameters controlling maturation. Hydrocarbon yield rates as determined by these experiments are shown in Fig. 6.9a. Both nonlinear optimization technique (Levenberg-Marquardt method Press et al. 1986 Issler and Snowdon 1990) and linear methods are used to determine the values of the reaction parameters Aj, Ej, andX, . This technique minimizes an error function by comparing the hydrocaibon release rates, Sj, calculated by Eq. 6.9 and those rates measured in open-system pyrolysis. An example of the spectrum of activation energies obtained from this analysis is shown in Fig. 6.9b. 

Though the detailed pros and cons of different types of pyrolysis apparatus are discussed elsewhere, we feel obUged to share our own experience, woiking for 6 years with the CDS Pyroprobe 120. This system is weU known and in wide use. It produces a highly predictable temperature time profile for the filament and provides a means of varying the heating rate linearly over the initial temperature rise period (ramp control). 

Pyrolysis products from organometallic phosphazenes can give nano-structured materials. Mixtures of AuCllPPhs) and poly[2,2 -dioxy-l,l -biphenylphosphazene] were pyrolyzed by heating the sample at 10 °C/min. to 800 °C, which was held for 2 hours under a flow of air. Characterization of the products by X-ray diffraction revealed a nanostructured Au material. Additional experiments were performed with metal centers directed bound to the phosphazene substrate. Structure (43) shows a phosphazene linear polymer substituted with 2,2 -biphenol and 4-hydroxyphenylacetonitrile pendant groups, with ruthenium coordinated to the terminal cyano groups. 

---