The deactivating effect of S02 on the reaction rate of the selective catalytic reduction of NO by NH3 over a vanadia-alumina catalyst was examined. A two-parameter model developed in the companion paper (Nam, I.; Eldrldge, J. W.; Kittrell, J. R. Ind. Eng. Chem. Prod. Res. Dev., preceding paper in this issue) was extended to the analysis of the deactivation data. The activation energies for both fresh and deactivated catalysts were similar. The sulfur content of the catalyst, as well as its surface area, appears to be a dominant deactivation parameter, analogous to coke-induced deactivation. Pore size distribution changes indicate that deactivation In this reaction system involves pore filling and plugging by the deactivating agent. That agent appears to be aluminum sulfate, on the basis of experimental results obtained from thermal gravimetric analyses. An empirical exponential dependence of catalyst activity on the catalyst sulfur content was observed for both primary reactions, NO reduction and NH3 oxidation.

Table S2. Data Collection and Crystallographic Parameters for the Hydrated and Dehydrated Forms of K +-Exchanged Gallosilicate Natrolites with Different Degrees of T-atom Ordering material K-GaNAT-I(E) K-GaNAT-II(E) K-GaNAT-III(E) K-GaNAT-I(EC) K-GaNAT-II(EC) K-GaNAT-III(EC) unit cell composition

Aims:  To investigate biohydrogenation of linoleic acid by rumen fungi compared with rumen bacteria, and to identify the fungus with the fastest biohydrogenation rate. Methods and Results:  Biohydrogenation of linoleic acid by mixed rumen fungi and mixed rumen bacteria were compared in vitro. With mixed rumen bacteria, all biohydrogenation reactions were finished within 100 min of incubation and the end product of biohydrogenation was stearic acid. With mixed rumen fungi, biohydrogenation proceeded more slowly over a 24‐h period. Conjugated linoleic acid (CLA; cis‐9, trans‐11 C18 : 2) was an intermediate product, and vaccenic acid (VA; trans‐11 C18 : 1) was the end product of biohydrogenation. Fourteen pure fungal isolates were tested for biohydrogenation rate. DNA sequencing showed that the isolate with the fastest rate belonged to the Orpinomyces genus. Conclusions:  It is concluded that rumen fungi have the ability to biohydrogenate linoleic acid, but biohydrogenation is slower in rumen fungi than in rumen bacteria. The end product of fungal biohydrogenation is VA, as for group A rumen bacteria. Orpinomyces is the most active biohydrogenating fungus. Significance and Impact of the Study:  This is the first study to demonstrate that rumen fungi can biohydrogenate fatty acids. Fungi could influence CLA content of ruminant products.

A model is presented which provides a relationship between catalyst activity and catalyst coke content, based upon the formation of both monolayer and multilayer coke. The model adequately fits experimental data which previously had required three separate emplrlcal activity-coke deactivation models, based upon linear, exponential, or hyperbolic equation forms. I n addition, it exhibits the proper functional form to describe typical coke-time data, such as that represented by the Voorhies relatlonshlp. The model is capable of describing observed temperature dependencies of coke-Initiated deactivation.Deactivation of a solid catalyst by a coking mechanism is often extremely complex, because coke precursors can arise from reactant molecules, product molecules, reactive intermediates, and combinations thereof. Most mechanistic models of catalyst deactivation employ Langmuir isotherm theory in their derivation, leading either to the classical hyperbolic Hougen-Watson models or to power function models (for sparsely covered surfaces). Since the Langmuir isotherm presumes monolayer surface coverage and since coke accumulation often far exceeds that associated with monolayer coverage (reaching levels of 5 to 20 wt %), modeling of coke-related deactivation is often undertaken using empirical relationships between catalyst activity and catalyst coke content.

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Indiscriminate use of antibiotics can result in antibiotic residues in animal products; thus, plant compounds may be better alternative sources for mitigating methane (CH4) production. An in vitro screening experiment was conducted to evaluate the potential application of 152 dry methanolic or ethanolic extracts from 137 plant species distributed in East Asian countries as anti-methanogenic additives in ruminant feed. The experimental material consisted of 200 mg total mixed ration, 20 mg plant extract, and 30 mL diluted ruminal fluid-buffer mixture in 60 mL serum bottles that were sealed with rubber stoppers and incubated at 39 °C for 24 h. Among the tested extracts, eight extracts decreased CH4 production by >20%, compared to the corresponding controls: stems of Vitex negundo var. incisa, stems of Amelanchier asiatica, fruit of Reynoutria sachalinensis, seeds of Tribulus terrestris, seeds of Pharbitis nil, leaves of Alnus japonica, stem and bark of Carpinus tschonoskii, and stems of Acer truncatum. A confirmation assay of the eight plant extracts at a dosage of 10 mg with four replications repeated on 3 different days revealed that the extracts decreased CH4 concentration in the total gas (7–15%) and total CH4 production (17–37%), compared to the control. This is the first report to identify the anti-methanogenic activities of eight potential plant extracts. All extracts decreased ammonia (NH3-N) concentrations. Negative effects on total gas and volatile fatty acid (VFA) production were also noted for all extracts that were rich in hydrolysable tannins and total saponins or fatty acids. The underlying modes of action differed among plants: extracts from P. nil, V. negundo var. incisa, A. asiatica, and R. sachalinensis resulted in a decrease in total methanogen or the protozoan population (p < 0.05) but extracts from other plants did not. Furthermore, extracts from P. nil decreased the population of total protozoa and increased the proportion of propionate among VFAs (p < 0.05). Identifying bioactive compounds in seeds of P. nil by gas chromatography-mass spectrometry analysis revealed enrichment of linoleic acid (18:2). Overall, seeds of P. nil could be a possible alternative to ionophores or oil seeds to mitigate ruminal CH4 production.

NH,, 7664-41-7; V, 7440-62-2; Cr, 7440-47-3; Fe, 7439-89-6. L i t e r a t u r e C i t e d Registry No. Bauerie, G. L.; Wu, S. C.; Nobe, K. Ind. Eng. Chem. Prod. Res. Dev. 1075, Chertov, V. M.; Okopnaya, N. T. Kinet. Katal. 1078, 19, 1595. Cole, D. J.; Cullis, C. F.; Hucknaii, D. J. J . Chem. SOC., Faraday Trans. Inornata, M.; Miyamoto, A.; Murakami, Y. Chem. Lett. 1078, 799. Inomata, M.; Miyamoto, A,; Murakami. Y. J . Catal. 1880, 62, 140. Inomata, M.; Miyamoto, A,; Murakami, Y. J. Phys. Chem. 1081, 85, 2372. Inomata, M.; Miyamoto, A.; UI, T.; Kobayashi, K.; Murakami, Y. Ind. Eng. Inomata, M.; Mori, K.; Miyamoto, A,; Ui, T.; Murakami, Y. J . Phys. Chem. Inomata, M.; Mori, K.; Miyamoto, A.; Murakami, Y. J . Phys. Chem. 1083b, Kasaoka, S.; Yamanaka, T. Nippon Kagaku Kaishl 1077, 6 , 907. Kato, A.; Matsuda, S.; Nakajima, F.; Inamari, M.; Watanabe, Y. J. Phys. Kato, A.; Matsuda, S.; Kamo, T. Ind. Eng. Chem. Prod. Res. Dev. 1083, Markvart, M.; Pour, V. C. J . Catal. 1087, 7 , 279. 14, 268. 1078, 72, 2185. Chem. Prod. Res. Dev. 1982, 21, 424. 10838, 87, 754. 87, 761. Chem. 1081, 85, 1710. 22, 406. Matsuda, S.; Takeuchl, M.; Hishinuma, Y.; Nakajim, F.; Narita, T.; Watanabe, Miyamoto, A.; Yamazaki, Y.; Inomata, M.; Murakami, Y. J. Phys. Chem. Miyamoto, A.; Yamazaki, Y.; Hattori, T.; Inomata, M.; Murakami, Y. J. Catal. Miyamoto, A.; Kobayashi, K.; Inomata, M.; Murakami, Y. J. Phys. Chem. Nakajima, F.; Takeuchi, M.; Matsuda, S.; Uno, S.; Mori, T.; Watanabe, Y.; Naruse, Y.; Ogasawara, T.; Hata, T.; Kishitake, H. Ind. Eng. Chem. Prod. Niiyama, H.; Ookawa, T.; Echigoya, E. Nippon KagakuKaishi 1075, 2 , 1871. Niiyama, H.; Murata, K.; Echigoya, E. Geus, J. W.; Geiiings. P. J. Ind. Eng. Shikada, T.; Fujimoto, K.; Kunugi, T.; Tominaga, H.; Kaneko, S.; Kubo, Y. Takagi, M.; Kawai, T.; Soma, M.; Onishi, T.; Tamaru, K. J . Phys. Chem. Tauster, S. A vanadla-alumina catalyst (10% V, O, on AI,O,) was employed in a packed-bed, tubular reactor to obtain kineticThe deactivating effect of SO2 on the reaction rate of the selective catalytic reduction of NO by NH, over a vanadia-alumina catalyst was examined. A two-parameter model developed in the companion paper (Nam, I.; Eldridge, J. W.; Kittrell, J. R. Znd. Eng. Chern. Prod. Res. Dev., preceding paper in this issue) was extended to the analysis of the deactivation data. The activation energies for both fresh and deactivated catalysts were similar. The sulfur content of the catalyst, as well as its surface area, appears to be a dominant deactivation parameter, analogous to coke-induced deactivation. Pore size distribution changes indicate that deactivation in this reaction system involves pore filling and plugging by the deactivating agent. That agent appears to be aluminum sulfate, on the basis of experimental results obtained from thermal gravimetric analyses. An empirical exponential dependence of catalyst activity on the catalyst sulfur content was observed for both primary reactions, NO reduction and NH, oxidation.