Toluene Diisocyanate

C₉H₆N₂O₂

Precursor for flexible polyurethane foam

Molecular Structure

Toluene Diisocyanate molecular structure
2D structure of Toluene Diisocyanate

Molecular Details

Molecular FormulaC₉H₆N₂O₂
Molecular Weight174.16 g/mol
StateLiquid at standard conditions

Olefinverbund Integration

⬅️ Inputs (Starting Materials): Toluene, Nitric Acid, Phosgene

➡️ Outputs (Products): Polyurethane Foam

Chemistry & Engineering

Reaction EquationNitration -> Hydrogenation -> Phosgenation
ThermodynamicsExothermic steps
Catalyst SystemNi (Hydrogenation)
Reactor ClassMultiple units
Process ConsiderationsMixture of 2,4 and 2,6 isomers.

Extraterrestrial Production Pattern

  1. Toluene → dinitrotoluene (nitration)
  2. Dinitrotoluene → toluenediamine (hydrogenation)
  3. TDA + phosgene → TDI + HCl
  4. Distillation for isomer separation

Applications

  • Flexible polyurethane foam
  • Coatings and elastomers
  • Adhesives

Reaction Diagram

Reaction diagram
Synthesis reaction pathway

Overall Reaction: C6H3(CH3)(NH2)2 + 2COCl2 -> C6H3(CH3)(NCO)2 + 4HCl

Unit Operations

Process steps following chemical engineering unit operation principles:

StepOperationDescription
1TDA ProductionHydrogenate dinitrotoluene to toluenediamine
2PhosgenationReact TDA with phosgene in chlorobenzene
3DegassingRemove HCl and excess phosgene
4Solvent StrippingStrip chlorobenzene solvent
5Isomer SeparationDistill to separate 2,4- and 2,6-TDI
6BlendingBlend 80/20 or 65/35 isomer ratios

S88 Batch Control Model

This module follows the ISA-88 (S88) batch control standard. Below is a simplified BatchML schema for educational purposes:

<?xml version="1.0" encoding="UTF-8"?>
<!-- ISA-88 Batch Control Model for Toluene Diisocyanate -->
<!-- Educational schema - simplified for demonstration -->
<BatchML xmlns="http://www.wbf.org/xml/B2MML-V0600">
  
  <ProcessCell ID="TDI_PLANT_CELL">
    <Description>Process cell for Toluene Diisocyanate production</Description>
    
    <Unit ID="TDI_PLANT">
      <Description>Main synthesis unit</Description>
      
      <!-- Equipment Modules -->
      <EquipmentModule ID="HYDROGENATOR">
        <Description>Hydrogenator</Description>
      </EquipmentModule>
      <EquipmentModule ID="PHOSGENE_REACTOR">
        <Description>Phosgene Reactor</Description>
      </EquipmentModule>
      <EquipmentModule ID="DEGASSER">
        <Description>Degasser</Description>
      </EquipmentModule>
      <EquipmentModule ID="STRIPPER">
        <Description>Stripper</Description>
      </EquipmentModule>
      <EquipmentModule ID="COLUMN">
        <Description>Column</Description>
      </EquipmentModule>
      <EquipmentModule ID="BLENDER">
        <Description>Blender</Description>
      </EquipmentModule>
    </Unit>
  </ProcessCell>
  
  <MasterRecipe ID="TDI_PLANT_RECIPE">
    <Description>Master recipe for Toluene Diisocyanate</Description>
    <ProductID>TOLUENE_DIISOCYANATE</ProductID>
    
    <UnitProcedure ID="TDI_PLANT_UP">
      <Description>Unit procedure for synthesis</Description>
      
      <Operation ID="OP_01">
        <Description>Operation 1</Description>
        <Phase ID="TDA_PROD">
          <Description>Tda Prod phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
      
      <Operation ID="OP_02">
        <Description>Operation 2</Description>
        <Phase ID="PHOSGENATE">
          <Description>Phosgenate phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
      
      <Operation ID="OP_03">
        <Description>Operation 3</Description>
        <Phase ID="DEGAS">
          <Description>Degas phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
      
      <Operation ID="OP_04">
        <Description>Operation 4</Description>
        <Phase ID="STRIP">
          <Description>Strip phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
      
      <Operation ID="OP_05">
        <Description>Operation 5</Description>
        <Phase ID="SEPARATE">
          <Description>Separate phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
      
      <Operation ID="OP_06">
        <Description>Operation 6</Description>
        <Phase ID="BLEND">
          <Description>Blend phase</Description>
          <PhaseLogic>
            <Step ID="STEP_1"><Action>Initialize</Action></Step>
            <Step ID="STEP_2"><Action>Execute</Action></Step>
            <Step ID="STEP_3"><Action>Complete</Action></Step>
          </PhaseLogic>
        </Phase>
      </Operation>
    </UnitProcedure>
  </MasterRecipe>
  
</BatchML>

**Key S88 Concepts:**
- **Process Cell**: The physical grouping containing all equipment for this process
- **Unit**: The major equipment that performs the synthesis
- **Equipment Modules**: Individual pieces of equipment (reactors, columns, etc.)
- **Unit Procedure**: The sequence of operations to produce the product
- **Phases**: The lowest level of procedural control (e.g., REACT, SEPARATE, PURIFY)

Key S88 Concepts:
Process Cell: Physical grouping containing all equipment
Unit: Major equipment performing synthesis
Equipment Modules: Individual pieces (reactors, columns, etc.)
Phases: Lowest level of procedural control (REACT, SEPARATE, etc.)


This Synthesis Module is part of the 100chemicals Olefinverbund — an integrated chemical production network designed for extraterrestrial civilization on Moon and Mars.