Let's break down the **production of acetone via isopropanol dehydrogenation** and how you would simulate and design this process in Aspen Plus (COCO is similar, but Aspen is more common). We'll cover: 1. **Process Chemistry** 2. **Material Balance** 3. **Process Flow Diagram** 4. **Simulation Steps** 5. **Key Design Points** 6. **Final Answers/Summary** --- ## 1. **Process Chemistry** **Reaction:** \[ \text{Isopropanol (IPA)} \rightarrow \text{Acetone} + \text{Hydrogen} \] \[ \mathrm{C_3H_8O} \rightarrow \mathrm{C_3H_6O} + \mathrm{H_2} \] - One mole of IPA produces one mole of acetone and one mole of hydrogen. - Reactor conditions: 400°C, 2 atm, copper-based catalyst. --- ## 2. **Material Balance** **Given:** - **Annual acetone production:** 10,000 metric tons/year - **Operating days:** 330 days/year - **Acetone purity:** 99.5% - **IPA feed:** 5 atm, 40°C, 99.9% purity ### **Step 1: Calculate Required Acetone per day** \[ 10,000 \text{ ton/year} \div 330 \text{ days/year} = 30.3 \text{ ton/day} \] ### **Step 2: Convert to kmol/day** - **Molecular weight (MW) of acetone (C3H6O):** 58.08 g/mol = 0.05808 kg/mol - **1 ton = 1000 kg** \[ 30.3 \text{ ton/day} = 30,300 \text{ kg/day} \] \[ \text{Moles acetone/day} = \frac{30,300 \text{ kg/day}}{0.05808 \text{ kg/mol}} \approx 521,585 \text{ mol/day} \] \[ = 521.6 \text{ kmol/day} \] ### **Step 3: Acetone at 99.5% Purity** \[ \text{Actual acetone mass needed} = \frac{30,300}{0.995} = 30,453 \text{ kg/day} \] \[ \text{Moles acetone/day} = \frac{30,453}{0.05808} = 524,275 \text{ mol/day} \approx 524.3 \text{ kmol/day} \] ### **Step 4: IPA Required** - **Stoichiometry:** 1 mol IPA → 1 mol acetone So, **IPA required = 524.3 kmol/day** - **IPA MW:** 60.1 g/mol = 0.0601 kg/mol - **IPA mass/day:** \( 524,300 \text{ mol/day} \times 0.0601 \text{ kg/mol} = 31,497 \text{ kg/day} \) --- ## 3. **Process Flow Diagram (PFD) – Overview** **Main units:** 1. **Feed tank:** Receives IPA at 5 atm, 40°C, 99.9% 2. **Preheater:** Heats IPA to 400°C 3. **Reactor:** Fixed-bed, copper catalyst, 400°C, 2 atm 4. **Condenser:** Cools reactor effluent 5. **Separator:** Separates acetone, hydrogen, and unreacted IPA 6. **Distillation column:** Purifies acetone to 99.5% --- ## 4. **Simulation Steps (e.g., in COCO or Aspen)** #### **A. Set up Components** - Define: IPA, acetone, hydrogen, (and water if considering side reactions). #### **B. Specify Feed Stream** - **Flow:** 31,497 kg/day IPA, 99.9% purity, 5 atm, 40°C #### **C. Heater/Preheater** - Heat the feed to 400°C #### **D. Reactor** - **Type:** PFR or fixed-bed reactor - **Reaction:** IPA → Acetone + H₂, 100% conversion assumed for base design - **Operating conditions:** 400°C, 2 atm #### **E. Cooler/Condenser** - Cool reactor outflow to condense acetone and IPA, leaving H₂ as gas. #### **F. Separator** - **Vapor:** Hydrogen (remove or use as fuel) - **Liquid:** Acetone + IPA #### **G. Distillation Column** - **Goal:** Acetone product at 99.5% purity - **Bottoms:** Recycle or waste IPA #### **H. Product Stream** - Acetone at desired purity, 524.3 kmol/day (30,453 kg/day) --- ## 5. **Key Design Points and Notes** - **Reactor:** Must maintain copper catalyst at 400°C, 2 atm. - **Hydrogen:** Can be recovered or combusted for process heat. - **Recycle:** Unreacted IPA can be recycled to reactor feed. - **Purity:** Final acetone purity controlled by distillation. --- ## 6. **Final Answers / Summary Table** | Item | Value | |--------------------------|----------------------| | Acetone production | 10,000 t/y | | Days/year | 330 | | Acetone/day | 30,300 kg (99.5%) | | Acetone moles/day | 524,300 mol (524.3 kmol) | | IPA required/day | 31,497 kg (524.3 kmol) | | Reactor conditions | 400°C, 2 atm | | IPA feed conditions | 5 atm, 40°C, 99.9% | | Main steps | Preheat, react, cool, separate, distill | --- ### **Explanation Recap** - The process is a **single-step dehydrogenation** of IPA. - **1:1 stoichiometry**: For every mole of acetone, you need one mole of IPA. - You **calculate daily production** based on annual requirement and operating days. - **Feed preparation**: IPA is preheated, then reacted at high temperature with a catalyst. - **Separation**: After reaction, acetone is separated and purified; hydrogen is collected as a by-product. --- ### **Simulation in COCO (or Aspen)** 1. **Set up components** in the simulator. 2. **Create process streams** (feed, products, recycle if any). 3. **Add unit operations:** Heater, reactor, cooler, separator, distillation column. 4. **Enter stoichiometry** and reaction kinetics if known. 5. **Run simulation** and check mass balances. 6. **Optimize** for IPA conversion, acetone purity, energy use. --- ## **Final Answer** To produce **10,000 metric tons/year of acetone (99.5% purity) via isopropanol dehydrogenation**, you need **524.3 kmol/day (31,497 kg/day) of isopropanol feed**. The process involves preheating IPA to 400°C, reacting it over a copper-based catalyst at 2 atm, cooling the product, separating acetone, hydrogen, and unreacted IPA, and finally purifying acetone via distillation. **Simulation (e.g., in COCO):** - Define components, feed conditions, reactions, and unit operations. - Ensure mass balance and process conditions are met. - The process is efficient, producing one mole of acetone and one mole of hydrogen per mole of IPA. **Summary Table:** | Acetone production | 10,000 t/year (99.5%) | |--------------------|----------------------| | IPA required | 31,497 kg/day (99.9%)| | Reactor conditions | 400°C, 2 atm | | Byproduct | Hydrogen (524.3 kmol/day) | --- If you need a **detailed simulation guide (step-by-step COCO flowsheet)** or an example simulation file, let me know!