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Toluene diisocyanate (TDI) is a widely used intermediate in the production of polyurethanes. Phosgenation reaction is the most important operation in the process of producing TDI, which is commonly performed in a jet reactor. Because of the high toxicity of phosgene, it is unpractical to evaluate the performance of the reaction by sampling intermediate products. To overcome this difficulty, first, a mapping table was created for reaction path and temperature. Next, various parameters that affect temperature, such as reaction path, ratio of phosgene, diethyl iso-phthalate (DEIP), etc. were investigated by simulation studies. The results show that the ratio of phosgene is the most important parameter. On the basis of the mapping table, easily available experimental reaction temperature data can be utilized to infer the reaction path, and consequently the performance of jet reactor can be predicted. The method was validated after being used in an experimental setup of 1000 tons/annum TDI capacity.

In order to separate the gas–liquid products from new ejector singlet oxygen generator (SOG) effectively, we designed a new type of gas–liquid cyclone. The classical Muschelknautz cyclone model method, the improved method and computational fluid dynamics (CFD) code's discrete phase model (DPM) and eddy diffusion concept (EDC) were used for the new type separator's calculation and simulation. The results show that: (1) Compared with classical Muschelnautz model, the improved Muschelknautz model can predict the cyclone's separation performance more accurately; (2) On the design conditions, the smaller droplets have more complex trajectories. For droplets larger than 3 μm, their separation efficiency is over 80% in the new separator; (3) The droplets' entrance locations affect the droplets' trajectories and separation efficiency, (4) The residence time which CFD predicts ranges from 1 to 50 ms and decreases with the droplets size increasing (5) The loss of O2(1 Δ) in the gas phase is less than 1% and it loses primarily on the gas–liquid contact reaction.