Epichlorohydrin (ECH) is a major raw material that can react with different classes of compounds to synthesize a wide variety of products required by industry. Now, the chlorohydrin method is the main method for producing ECH in industry. However, it has several serious disadvantages. Hydrogen peroxide is relatively non-toxic and widely regarded as an environmentally friendly green oxidant. Recently, the epoxidation of olefins with hydrogen peroxide as oxidant has attracted special attention (Li et al., 2006; Wang et al., 2007; Wroblewska and Fajdek, 2010). Titanium silicate 1 (TS-1) is an effective catalyst for the selective oxidation of hydrocarbons (Thomas and Raja, 2006; Baerlocher et al., 2007). Several studies have shown that the epoxidation of allyl chloride with epichlorohydrin hydrogen peroxide to synthesize ECH in the presence of TS-1 and organic solvents has broad industrial prospects (Pandey and Kumar, 2007; Wang et al., 2007; Kim et al., 2011). Solvents can be alcohols, ketones or ethers. Danov et al. (2012) showed that the highest epoxidation rates and satisfactory ECH yields were achieved with methanol. However, hydrogen peroxide may pose safety concerns when catalyzed by many materials because of its potentially highly exothermic decomposition into water and oxygen. Allyl chloride/oxygen and methanol/oxygen may create explosive systems in the gas phase of reactors and distillation columns. Therefore, the reaction of allyl chloride and hydrogen peroxide to produce ECH needs to pay attention to safety issues.
In this study, we present the design and control of a plant-wide ECH synthesis process via the epoxidation of allyl chloride with hydrogen peroxide over TS-1 catalyst in the presence of methanol. Steady-state and dynamic simulations were performed by Aspen Plus software. First, a kinetic and thermodynamic model is established. The whole plant process is then designed with safety in mind. Finally, the control strategy is constructed through the steady-state analysis of the whole plant process, and its control performance is evaluated through dynamic simulation.