Irreversible reaction

Loss to tert-butanol and isobutene (lumped acidic by-product path)

2KTBC+COCl2C4H10O+C4H8+3CO2+2ClK

Direction
Irreversible
Processes
1
Stated as
Rate law
Heat of reaction
ΔH = -175,200 kJ/kmol (one process)
Element balance
Checked: balances
As the processes state itStoichiometry, conversions, heats of reaction and catalyst windows are taken from each process's files with their provenance. The build checks only that each process's equation balances in every element, from the process's own component formulas; it does not check the numbers. A process's design maturity applies to them.

Species

SpeciesNameCASRoleCoefficient
KTBCPotassium tert-butyl carbonate (suspended)none (not merged across processes)reactant-2
COCl2Phosgene75-44-5reactant-1
C4H10Otert-Butanol (2-methylpropan-2-ol)75-65-0product1
C4H8Isobutene (2-methylpropene)115-11-7product1
CO2Carbon dioxide124-38-9product3
ClKPotassium chloride7447-40-7product2

In the processes

  • Di-tert-butyl dicarbonate by semi-batch carbonation and phosgenation of potassium tert-butoxide (500 t/a)Concept · not reviewed

    SIDE · Loss to tert-butanol and isobutene (lumped acidic by-product path)2 (CH3)3COC(O)OK + COCl2 → (CH3)3COH + C4H8 + 3 CO2 + 2 KCl

    Stated as
    Rate law
    Phase
    liquid
    Element balance
    Balances in every element
    Heat of reaction
    ΔH = -175,200 kJ/kmol at 298.15 K, as written (assumed: ASSUMED as PHOS (D-005, D-015), phosgene dissolved: the same reagents to KCl, the decomposition of the chloroformate taken as heat-neutral; no open value)
    Rate law
    basis: volume; driving: concentration; form: power_law; k: {"A":"9.2377e6","Ea":50000}; orders: {"COCL2":1,"KTBC":1}; temperature range: 263.15 – 303.15 (assumed: ASSUMED (D-005): 7 % of the phosgene to the side path, set so that the modelled isolated yield (89.4 % on the alkoxide) stays below the 91.0 % that EP 0 256 559 A2's Example 1 gives by mass (149 g from 1.5 mol of the alkoxide, its purity not stated in the text))

Sources

What the processes cite for this reaction, each source once: for the reaction itself, its conversion, its heat of reaction or its catalyst. As the processes write them; DOIs, US patent numbers and web addresses are linked.

  1. EP 0 256 559 A2, description: acidic by-products such as tert-butyl chloroformate form in the crude phosgenation mixture (named as what stopped the older decarboxylation)

    For the reaction · cited by Di-tert-butyl dicarbonate by semi-batch carbonation and phosgenation of potassium tert-butoxide (500 t/a)

  2. Wikipedia, Di-tert-butyl dicarbonate: decomposition gives tert-butanol, isobutene and CO2 (products only)

    For the reaction · cited by Di-tert-butyl dicarbonate by semi-batch carbonation and phosgenation of potassium tert-butoxide (500 t/a)

  3. ASSUMED as PHOS (D-005, D-015), phosgene dissolved: the same reagents to KCl, the decomposition of the chloroformate taken as heat-neutral; no open value

    For the heat of reaction · cited by Di-tert-butyl dicarbonate by semi-batch carbonation and phosgenation of potassium tert-butoxide (500 t/a)