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SynopsisPyrrole reacted with potassium persulfate in aqueous media to form polymers or "pyrrole blacks."The structure and molecular weight depend on the initial pyrrole/KzSzOs ratio. An ESR line due to trapped electrons or free radical ions appeared at g = 2.0036 (width 3.6 G ) in all products and its intensity decreased with an increase in initial concentration of potassium persulfate. RESULTSWhen pyrrole (fresh distilled pyrrole) solution in water was added to potassium persulfate solution or solid at room temperature the solution developed a dark color immediately and later deposited a black precipitate that could have been pyrrole black. This reaction was fast in comparison with the one in which pyrrole

The hydrotreatment of heavy gas oil derived from Athabasca bitumen was studied in a trickle bed reactor over Ni-Mo, Ni-W, and Co-Mo supported on alumina catalysts at 350 °C and 4.24-12.51 MPa. The effects of temperature, pressure, and liquid flow rates on the product were investigated.ASTM distillation, cetane index, aniline point, diesel index, C/H atomic ratio, viscosities, and densities of the product were measured and correlated with various parameters. The activities of the catalysts for hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) are compared. While Ni-W/ A1203 was best for cracking, hydrogenation, and hydrodesulfurization, Ni-Mo/Al203 was best for hydrodenitrogenation. The data were fitted to a pseudo-first-order reaction model for both HDS and HDN

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N a content. In the NaH-Ms with higher N a contents, the Na cation prefers position IV, which directly confronts the sorbed molecule in the channel. This produces a strong electrostatic field similar to that of pure Na-M and, therefore, results in a qst value close to that of pure Na-M as shown in Figure 3. On the other hand, Na may prefer position 11 in the NaH-Ms with its lower Na content. This produces a relatively weak electrostatic field as in pure H-M, resulting in as low a qst value as that of pure To solve question 3, we calculated the (ED + ER) values for three kinds of hypothetical zeolites which possess straight, cylindrical channels of 8-, lo-, or 12-membered rings stretching along the c axis as shown in Figure 6. Assuming that the oxygenoxygen distance and aOx value are 0.3 nm and 1.65 X m3, respectively, we summed up the contributions from -8000 oxygen atoms surrounding the origin contained in a cube of 6 X 6 X 6 nm3. The obtained ED + ER value at the positions on the line X (or Y) at Y = 2 = 0 (or X = 2 = 0) (see Figure 6) is shown in Figure 7. Figure 7 shows that the magnitude of the (ED + ER) value is a function of the size and shape of the zeolite channel. The l(ED + E R )~ value increases with a decrease in the channel size. This accords well with the result obtained for H-M and H-ZSM-5 as shown in Figure 5. The difference in the magnetic H-M.of the ED + ER value apparently observed between H-M and the hypothetical zeolite having the 12-membered-ring channel, or between H-ZSM-5 and the hypothetical zeolite having the 10-membered-ring channel, arises from the assumption that the oxygen-oxygen distance in the hypothetical zeolite is 0.3 nm. If we use the value of 0.25 nm for the distance which is close to the distance in H-M and H-ZSM-5, we can obtain for the hypothetical zeolites the same magnitude of (ED + ER) values as those for H-M and H-ZSM-5. Now it becomes quite certain that the channel size effects the magnitude of the (ED + ER) value. To obtain a I(ED + ER)I value smaller than the qst value = 3.5 kcal mol-' for Ar sorbed by H-ZSM-5, we should conclude that its a,, value is not 1.65 X m3 as already mentioned. This means that the electric charge of oxygen in H-ZSM-5 is smaller than that in H-M. The conclusion obtained above is fairly reaonsable if one notices the fact that H-ZSM-5 is more siliceous than H-M. Since the siliceous zeolite contains fewer aluminum atoms, the bonds between oxygen atoms and T (Le,, Si or Al) atoms in it become less ionic. m3 but smaller than 1.2 X Registry No. Ar, 7440-37-1; 02, 7782-44-7; N2, 7727-37-9; NO, 10102-43-9; CO, 630-08-0.Computational procedures are used to simulate aluminum distributions in faujasite frameworks assuming Loewenstein's rule is obeyed. Several models are used as a basis for these computations, and in each case the average occupancy, by aluminum, of "T" atoms second neighbor to each aluminum is calculated. Results so obtained are used in correlation of properties which depend upon zeolite acidity. IntroductionIn 1956 Loewenstein' propose...