Tham khảo tài liệu 'phân tích eclectron trong hóa phân tích phần 4', kỹ thuật - công nghệ, hoá học - dầu khí phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | while during balance 5 336 h the distribution was CH C2-C4 C5-C11 and C12 . The olefin paraffin ratios decreased with time for example the C2 ratio decreased from in balance 1 to in balance 5. A repeat of the conditions was made in balance 11 619 A after 5 balances at different process conditions. The H2 CO conversion dropped to in balance 11 showing that the process variable studies had accelerated deactivation of the catalyst. The trends in selectivity seen in balances 1-5 were also evident during balance 11. The weight of methane increased to and C12 decreased to . The weal trend in decreasing olefin paraffin ratios continued as well. During the process variable studies the effect of temperature was studied at NlỊg-cal-h in balances 8 235 C 5 250 C and 10 265 C and at Nl g-caz-h in balances 9 235 C and 7 250 C with all balances at MPa and H2 CO . A comparison of catalyst selectivity at these conditions appears in Fig. 27. Conversion increases as expected with temperature 235 C 250 C and 265 C at Nlfg-cax-h and 235 CC and 250 C at Nl g-cax-h. Temperature had little effect on the weight hydrocarbon distribution between 235 and 265 C 2 Nl g-caX-h and 235 and 250 C Nl g-ox-h . which is unexpected since selectivity typically shifts towards lower molecular weight products with increased temperature. Olefin paraffin ratios decreased with temperature presumably as hydrogenation activity increases with temperature. The feed gas space velocity was varied at 235 C in balances 9 NlỊg-c t-h and 8 NỈỊg-cat-ft and at 250 C in balances 7 Nl g-cat-h 5 IVZ p-cat-h and 6 ỉỉl g-caX-Ịì . Space velocity has a minimal effect on the weight hydrocarbon distribution as shown in Fig. 28. A space velocity of IVZ p-cat-h at 250 C tended to produce more lower molecular weight products than at higher space velocities but this trend was as strong at 235 C. Olefin paraffin .
