{
  "authors": [],
  "basis": {
    "capacity": "500 t/a distilled Boc2O: 762.5 batches/a of 655.71 kg in 7920 h on a dedicated train (63.13 kg/h year average), ASSUMED (DESIGN.md D-002, D-003, D-013)",
    "location": "generic fine-chemicals site with a captive phosgene unit and a thermal oxidiser (not chosen)",
    "operating_hours_per_year": 7920
  },
  "benchmarks": [
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "expression": "feed:PHOS / product:BOC",
      "family": "oxygenates",
      "kpi": "boc2o-specific-phosgene",
      "no_open_reference": "No open source with a plant's phosgene use per kg of Boc2O found (searched 2026-11-06 as for boc2o-specific-potassium-tert-butoxide); EP 0 256 559 A2 uses 0.54 to 1.5 mol per mol of the alkoxide in its examples (1.5 in Example 1, 1.50 kg/kg on its 149 g), laboratory ratios. Only the stoichiometric floor, 0.453 kg/kg, is known.",
      "problem": "1 to kg/kg needs core's foundation.units (pip install 'cheme-as-code[units]')",
      "reference": null,
      "status": "unchecked",
      "title": "Phosgene consumption per kg of di-tert-butyl dicarbonate",
      "unit": "kg/kg",
      "value": null
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "expression": "feed:KOTBU / product:BOC",
      "family": "oxygenates",
      "kpi": "boc2o-specific-potassium-tert-butoxide",
      "no_open_reference": "No open source with a plant's or a pilot's alkoxide use per kg of Boc2O found (searched 2026-11-06: Google Patents EP 0 256 559 A2 and US 5 151 542 A read, laboratory examples only; Wikipedia, Di-tert-butyl dicarbonate, routes without figures; web search for Boc2O production consumption figures, none found). EP 0 256 559 A2 Example 1 implies 1.13 kg/kg (168 g for 149 g, its purity not stated), US 5 151 542 A Example 1 about 1.18 kg/kg on its methanesulfonyl chloride route (3 mol for 285.8 g at 87 %), single values; the stoichiometric floor is 1.028 kg/kg.",
      "problem": "1 to kg/kg needs core's foundation.units (pip install 'cheme-as-code[units]')",
      "reference": null,
      "status": "unchecked",
      "title": "Potassium tert-butoxide consumption per kg of di-tert-butyl dicarbonate",
      "unit": "kg/kg",
      "value": null
    }
  ],
  "chemistry": {
    "inputs": [
      {
        "chemical": "potassium-tert-butoxide",
        "grade": null,
        "inventory_key": "feed:KOTBU",
        "note": "Potassium tert-butoxide (technical solid), 1.150 kg/kg Boc2O; linked to potassium-tert-butoxide-1 kg for kg (its make-up tert-butanol from tert-butanol-1, its potassium metal a gap there, D-012)",
        "role": "feedstock"
      },
      {
        "chemical": "phosgene",
        "grade": null,
        "inventory_key": "feed:PHOS",
        "note": "Liquid phosgene (phosgene-1), 0.497 kg/kg Boc2O, 0.49 mol per mol of the alkoxide, evaporated and dosed as gas",
        "role": "feedstock"
      },
      {
        "chemical": "carbon-dioxide",
        "grade": null,
        "inventory_key": "feed:CO2",
        "note": "CO2 gas (merchant), 0.587 kg/kg Boc2O, 1.3 mol per mol of the alkoxide; a gap",
        "role": "feedstock"
      },
      {
        "chemical": "n-hexane",
        "grade": null,
        "inventory_key": "feed:HEXMU",
        "note": "n-Hexane make-up (merchant), 0.113 kg/kg Boc2O, most of it lost with R-101's vent-condenser gases (the dosing's vent and the degassing's nitrogen sweep, saturated at 263 K); the strips recover the rest of the 7.94 kg/kg the charge holds",
        "role": "feedstock"
      },
      {
        "chemical": "triethylenediamine",
        "grade": null,
        "inventory_key": "feed:DABCO",
        "note": "DABCO catalyst (merchant), 0.0138 kg/kg Boc2O, 1.2 mol% of the alkoxide (EP 0 256 559 A2, Example 1)",
        "role": "feedstock"
      },
      {
        "chemical": "white-mineral-oil",
        "grade": null,
        "inventory_key": "feed:PARAF",
        "note": "Liquid paraffin make-up for the still's heel, 0.030 kg/kg Boc2O (the heel's 10 % purge)",
        "role": "feedstock"
      },
      {
        "chemical": "sodium-hydroxide",
        "grade": null,
        "inventory_key": "feed:NAOH",
        "note": "Caustic soda 50 wt% (chlor-alkali-1) to the scrubber, 0.164 kg/kg Boc2O, counted by mass of the solution",
        "role": "feedstock"
      },
      {
        "chemical": "water",
        "grade": null,
        "inventory_key": "feed:PW",
        "note": "Wash water and scrubber make-up, 4.18 kg/kg Boc2O",
        "role": "feedstock"
      },
      {
        "chemical": "nitrogen",
        "grade": null,
        "inventory_key": "consumable:nitrogen",
        "note": "Nitrogen (asu-1) for inerting, the degassing's sweep, purging and breaking the vacuums, 157.5 kg per batch, 0.240 kg/kg Boc2O (ASSUMED)",
        "role": "feedstock"
      }
    ],
    "outputs": [
      {
        "chemical": "di-tert-butyl-dicarbonate",
        "grade": null,
        "inventory_key": "product:BOC",
        "note": "Distilled Boc2O melt to heated storage; modelled 99.98 wt%, an upper bound: di-tert-butyl carbonate, the tricarbonate and other by-products are not modelled",
        "role": "main-product"
      },
      {
        "chemical": "wastewater",
        "grade": null,
        "inventory_key": "product:AQ",
        "note": "Wash brine, 4.35 kg/kg Boc2O: about 17 wt% KCl with tert-butanol, DABCO and the unreacted carbonate, to wastewater treatment",
        "role": "waste"
      },
      {
        "chemical": "wastewater",
        "grade": null,
        "inventory_key": "product:WS",
        "note": "Spent scrubber liquor, 0.836 kg/kg Boc2O, sodium carbonate with excess NaOH, to wastewater treatment",
        "role": "waste"
      }
    ],
    "utilities": [
      {
        "chemical": "electricity",
        "grade": null,
        "inventory_key": "feed:POWER",
        "note": "0.424 kWh/kg Boc2O: agitators of R-101, V-201 and C-301, the three vacuum pumps, the scrubber's pump and fan (ASSUMED)",
        "role": "utility"
      },
      {
        "chemical": "steam",
        "grade": null,
        "inventory_key": "feed:LPS",
        "note": "1.209 kWh (4.35 MJ)/kg Boc2O of LP steam through hot-water circuits: the hexane strips (0.970 kWh with the charge's heat-up and V-201's sensible heat), the still (0.107 kWh), the wash water, the phosgene evaporator and the degassing",
        "role": "utility"
      },
      {
        "chemical": "chilled-water",
        "grade": null,
        "inventory_key": "product:CHW",
        "note": "0.925 kWh/kg Boc2O removed by chilled water at 278 K: the strips' and the forerun's condensers",
        "role": "utility"
      },
      {
        "chemical": "chilled-water",
        "grade": null,
        "inventory_key": "product:BRINE",
        "note": "0.524 kWh/kg Boc2O removed by brine at 258 K: R-101's charge cooling, the heats of carbonation and phosgenation with the gases' heats of solution, and R-101's vent condenser (R101's model) (the registry has chilled water, not brine: closest entry)",
        "role": "utility"
      },
      {
        "chemical": "cooling-water",
        "grade": null,
        "inventory_key": "product:CW",
        "note": "0.123 kWh/kg Boc2O removed by cooling water: the main-cut condenser and product cooler, and the scrubber",
        "role": "utility"
      }
    ]
  },
  "description": "The route is the one-pot phosgene route of EP 0 256 559 A2 (Mitsubishi Kasei, 1986/1988): per\nmol of potassium tert-butoxide 1.3 mol of CO2 (US 5 151 542 A, Example 1: 4 mol on 3) and 0.49\nmol of phosgene (EP Examples 6-7 use 0.54; a 2 % deficit on the net reaction's 0.5 is ASSUMED,\nso that no phosgene is left for the work-up), with 1.2 mol% DABCO (EP Example 1). The\ncarbonate forms from the suspended alkoxide and the dissolved CO2 (85 % of the dose taken up,\nthe rest vented); the phosgene and the amine give Boc2O, KCl and CO2 directly (the patent's\npoint: no tricarbonate is isolated), 7 % of the phosgene going to a lumped side path to\ntert-butanol, isobutene and CO2 (ASSUMED). The patent's own example runs in THF; hexane, an\naliphatic hydrocarbon within its claimed solvents and the Sumitomo patent's solvent, is\nASSUMED here so that the KCl is washed out with water after the solvent strip and no THF must be\nswapped out. The slurry is degassed with a nitrogen sweep, the hexane stripped at 15 and then 1 kPa(a) at up to\n313 K (both patents keep Boc2O below 50 C when the solvent is removed), the melt washed with\nwarm water and split from the KCl brine, and the Boc2O distilled at 0.13 kPa(a) from a liquid\nparaffin, which EP 0 256 559 A2 adds to suppress decomposition; the heel returns to the next\nbatch with a 10 % purge. The modelled yield is 89.4 % on the alkoxide and 91.2 % on\nphosgene: below the 91.0 % EP 0 256 559 A2's Example 1 gives by mass (149 g from 1.5 mol, its\npurity not stated in the text), so that source bounds it from above. The modelled product is\n99.98 wt% Boc2O, an upper bound: di-tert-butyl carbonate, the tricarbonate and other\nby-products are not modelled (US 5 151 542 A reports 98.6 to 99.7 % for its route).\n\nThe batch is modelled with cheme-as-code 1.10.0: R101 is a semi-batch (reactor: semibatch) with\ntwo gas doses (dosing.absorbed, with their heats of solution, core ADR 0063) and a vent for the\nCO2 and isobutene (batch.vent, core ADR 0054) that carries the slurry's hexane and phosgene\nvapour through R-101's vent condenser (vent.vapour, vent.condenser, ADR 0062); the degassing\nand the three distillations are core's batch stills (ADR 0055), the first strip with its\ncharge's heat-up; both recycles, the recovered hexane and the paraffin heel, are tear streams\nconverged by propagate (ADR 0060); the semi-batch's, its vent condenser's and the stills' duties\ncome from their models (ADR 0059). The recipe gives the cycle (10.39 h, R-101 the bottleneck,\n762.5 batches a year), sizes R-101, V-201 (12.5 m3 each) and C-301 (1.6 m3) and checks R-101's\njacket (98.4 kW against the model's 73.8 kW peak). Kinetics and heats of reaction are ASSUMED\n(no open data): the phosgene accumulates 2.7 % at the end of its dosing (36.1 % at k/100); the\nMTSR is 279.5 K against an MTT of 333.15 K, the decomposition limit (Boc2O's precursors gave\nvigorous gas at 60-70 C, US 5 151 542 A), and a cooling failure releases at most 24.5 m3/h of\ngas with its vapour against the vent's 50 m3/h (52.9 m3/h at k/100, 1.06 of it: a design\nfinding). No TD24 is known: no class. See DESIGN.md for every assumption.\n",
  "design_basis": {
    "assumptions": [
      "Route: the one-pot phosgene route of EP 0 256 559 A2 (alkoxide carbonated with CO2, then phosgene with DABCO, no tricarbonate isolated), in hexane instead of the example's THF (ASSUMED, within the claimed solvents; D-001).",
      "ASSUMED effective rate laws: CARB k 0.05 m3/(kmol s), PHOS 0.05 and SIDE 0.0038 at 278 K (7 % of the phosgene to the side path); the 2.7 % phosgene accumulation follows from them (D-005, D-011).",
      "Stills: Raoult's law with NIST Antoine constants (an ideal liquid, ASSUMED), Boc2O's vapour pressure ASSUMED from one open point; the degassing (a nitrogen sweep at 30 kPa(a)) at ASSUMED constant volatilities, its CO2 volatility set so that its gas carries the hexane that saturates R-101's vent-condenser gas over the batch (D-006, D-008).",
      "The wash's split and the scrubber's CO2 uptake are specified (ASSUMED, D-007); all flows are year averages of the recipe (D-003); accuracy +/-30 % not demonstrated."
    ],
    "source": "process/design-basis.yaml"
  },
  "engineering": {
    "description": "Di-tert-butyl dicarbonate (Boc2O) by semi-batch carbonation and phosgenation of potassium tert-butoxide in hexane with a CO2 vent, hexane strips, a water wash and vacuum distillation from a paraffin heel, a batch plant, concept stage (issue ChemE-as-Code/process-library#160)",
    "name": "Di-tert-butyl dicarbonate",
    "requires": "cheme-as-code>=1.10",
    "stage": "concept",
    "stages": [
      {
        "id": "concept",
        "title": "Concept and feasibility"
      },
      {
        "id": "basic",
        "title": "Basic engineering"
      },
      {
        "id": "detail",
        "title": "Detail engineering"
      }
    ],
    "tool": "plantcode"
  },
  "facets": {
    "feedstock_basis": [
      "fossil",
      "mineral",
      "electricity"
    ],
    "product_classes": [
      "chemicals"
    ],
    "region": "generic",
    "unit_operations": [
      "reaction",
      "distillation",
      "extraction",
      "absorption"
    ]
  },
  "families": [
    "oxygenates"
  ],
  "gap_count": 10,
  "gates": null,
  "id": "di-tert-butyl-dicarbonate-1",
  "issues": {
    "closed_count": 0,
    "list_url": "https://github.com/ChemE-as-Code/process-library/issues?q=is%3Aissue%20label%3A%22process%3Adi-tert-butyl-dicarbonate-1%22",
    "new": {
      "action": "https://github.com/ChemE-as-Code/process-library/issues/new?template=1-action-item.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1",
      "change": "https://github.com/ChemE-as-Code/process-library/issues/new?template=4-design-change.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1",
      "hold": "https://github.com/ChemE-as-Code/process-library/issues/new?template=2-engineering-hold.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1",
      "process": "https://github.com/ChemE-as-Code/process-library/issues/new?template=6-process-development.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1",
      "tq": "https://github.com/ChemE-as-Code/process-library/issues/new?template=3-technical-query.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1",
      "tracker": "https://github.com/ChemE-as-Code/process-library/issues/new?template=7-process-tracker.yml&labels=process%3Adi-tert-butyl-dicarbonate-1&process=di-tert-butyl-dicarbonate-1"
    },
    "open": [],
    "open_by_gate": {},
    "open_count": 0,
    "private": false,
    "repository": "ChemE-as-Code/process-library"
  },
  "keywords": [
    "di-tert-butyl dicarbonate",
    "Boc anhydride",
    "Boc2O",
    "potassium tert-butoxide",
    "potassium tert-butyl carbonate",
    "carbon dioxide",
    "phosgene",
    "DABCO",
    "phosgenation",
    "carbonation",
    "semi-batch",
    "batch",
    "gas dosing",
    "CO2 vent",
    "hexane",
    "batch still",
    "vacuum distillation",
    "liquid paraffin",
    "caustic scrubber",
    "fine chemicals",
    "protecting group reagent"
  ],
  "lca": {
    "allocation": null,
    "backend": "factors",
    "boundary": "cradle-to-gate",
    "categories": [
      {
        "id": "climate-change",
        "method": "GWP100",
        "title": "Climate change",
        "unit": "kg CO2-eq"
      }
    ],
    "contributions": [],
    "data_sources": [],
    "factors_status": "none",
    "functional_unit": {
      "amount": 1,
      "chemical": "di-tert-butyl-dicarbonate",
      "grade": null,
      "label": "1 kg di-tert-butyl dicarbonate",
      "product": "BOC",
      "product_name": "Di-tert-butyl dicarbonate",
      "product_title": "Boc2O melt to heated storage",
      "unit": "kg"
    },
    "goal": "Preliminary gate-to-gate life cycle inventory of di-tert-butyl dicarbonate (Boc2O) made by the one-pot phosgene route: potassium tert-butoxide carbonated with CO2 and phosgenated with a DABCO catalyst in hexane (one semi-batch), the hexane stripped and recycled, the melt washed with water and distilled under vacuum from a liquid-paraffin heel, the vents scrubbed with caustic, at the concept stage: which raw materials, utilities and wastes the batch plant exchanges per kg of distilled Boc2O, as the foreground for a later cradle-to-gate study. No impact results: most backgrounds are not mapped yet (D-012).",
    "inventory": [
      {
        "direction": "input",
        "key": "feed:KOTBU",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.15048,
        "title": "Potassium tert-butoxide (merchant solid)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:HEXMU",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.113247,
        "title": "n-Hexane make-up (merchant)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:DABCO",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0138012,
        "title": "DABCO catalyst (merchant)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:CO2",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.586571,
        "title": "Carbon dioxide gas (merchant)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:PHOS",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.496929,
        "title": "Liquid phosgene (phosgene-1)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:PARAF",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.0303043,
        "title": "Liquid paraffin make-up (merchant white oil)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:PW",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 4.17606,
        "title": "Process water (wash, scrubber make-up)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:NAOH",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.164003,
        "title": "Caustic soda 50 wt% (chlor-alkali-1)",
        "unit": "kg"
      },
      {
        "direction": "input",
        "key": "feed:POWER",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.423725,
        "title": "Electric power",
        "unit": "kWh"
      },
      {
        "direction": "input",
        "key": "feed:LPS",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 1.2086,
        "title": "LP steam 350 kPa(a) (the tempered and hot-water circuits)",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:BOC",
        "kind": "material",
        "phase": "operation",
        "provenance": "calculated",
        "quantity": 1.0,
        "title": "Boc2O melt to heated storage",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:AQ",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 4.35214,
        "title": "Wash brine (KCl) to wastewater treatment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:WSOLV",
        "kind": "material",
        "phase": "operation",
        "provenance": "calculated",
        "quantity": 0.0538211,
        "title": "Forerun (hexane, water, tert-butanol) to solvent incineration",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:RES",
        "kind": "material",
        "phase": "operation",
        "provenance": "calculated",
        "quantity": 0.0387498,
        "title": "Paraffin heel purge to incineration",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:WS",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.835633,
        "title": "Spent scrubber liquor to wastewater treatment",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:VENT",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.451027,
        "title": "Scrubbed vent (CO2, isobutene, hexane) to the thermal oxidiser",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "product:CW",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.123395,
        "title": "Cooling water return",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:BRINE",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.524317,
        "title": "Chilled brine return (263 K)",
        "unit": "kWh"
      },
      {
        "direction": "output",
        "key": "product:CHW",
        "kind": "energy",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.924846,
        "title": "Chilled water return (283 K)",
        "unit": "kWh"
      },
      {
        "direction": "input",
        "key": "consumable:nitrogen",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.240198,
        "title": "Nitrogen for inerting R-101, sweeping the degassing, purging the phosgene line, breaking the vacuums and blanketing the tanks",
        "unit": "kg"
      },
      {
        "direction": "output",
        "key": "disposal:consumable.nitrogen",
        "kind": "material",
        "phase": "operation",
        "provenance": "assumed",
        "quantity": 0.240198,
        "title": "Disposal: Nitrogen for inerting R-101, sweeping the degassing, purging the phosgene line, breaking the vacuums and blanketing the tanks (through the vent header, the scrubber and the site's thermal oxidiser to air, unchanged (D-012))",
        "unit": "kg"
      }
    ],
    "no_total": {
      "baseline": {
        "climate-change": {
          "gaps": 20,
          "reason": "every-contribution-a-gap"
        }
      }
    },
    "not_computed": [
      "climate-change"
    ],
    "pcf": [],
    "publishable": true,
    "result": {
      "classification": "partial",
      "gaps": 20,
      "label": "partial screening carbon footprint",
      "publication": "public"
    },
    "sources": [
      "lca/README.md",
      "lca/dataset.yaml",
      "lca/factors.yaml",
      "lca/gaps.csv",
      "lca/inventory.csv",
      "lca/lca.yaml",
      "lca/mappings.yaml",
      "lca/results.csv",
      "lca/results.md"
    ],
    "totals": {
      "baseline": {}
    },
    "withheld_reason": null
  },
  "lci_gaps": [
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "feed:HEXMU",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "feed:DABCO",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "feed:CO2",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "feed:PARAF",
      "link": "technosphere",
      "type": "input"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "product:WSOLV",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "product:RES",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "product:VENT",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "product:BRINE",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "product:CHW",
      "link": "technosphere",
      "type": "output"
    },
    {
      "dataset": "di-tert-butyl-dicarbonate-by-semi-batch-carbonation-and-phosgenation-of-potassium-tert-butoxide-in-hexane",
      "key": "disposal:consumable.nitrogen",
      "link": "technosphere",
      "type": "output"
    }
  ],
  "maintainers": [
    {
      "name": "Artur Schweidtmann"
    }
  ],
  "maturity": "concept",
  "preliminary": true,
  "provenance": {
    "library_commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174",
    "previews": {
      "sheets": [
        "BFD",
        "PFD"
      ],
      "source_commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174",
      "tool": "cheme 1.6.0 (pyDEXPI 2.1.0)"
    },
    "previews_stale": false,
    "source_commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174"
  },
  "publication": {
    "license": "CC-BY-4.0",
    "status": "public"
  },
  "references": [
    {
      "title": "Mitsubishi Kasei (1986/1988) EP0256559A2: Process for the preparation of di-tert-butyl dicarbonate (alkali tert-butyl carbonate from the alkoxide and CO2, phosgene with a tertiary amine in an ether or hydrocarbon; washing out the alkali chloride, solvent removal under reduced pressure, distillation with a liquid paraffin; Example 1: 1.5 mol KOtBu, 3 mol CO2 over 3 h and 2.25 mol phosgene over 4 h at 5 C in THF with DABCO, 149 g; application refused)",
      "url": "https://patents.google.com/patent/EP0256559A2/en"
    },
    {
      "title": "Sumitomo Seika (1991/1992) US5151542A: Process for preparing di-tert-butyl dicarbonate (potassium tert-butoxide and CO2 in hexane, methanesulfonyl chloride; water washes, solvent removal at no more than 50 C under reduced pressure; 87 % and 99.7 % in Example 1; vigorous gas and 11 % at 60-70 C in Comparative Example 1)",
      "url": "https://patents.google.com/patent/US5151542A/en"
    },
    {
      "title": "Wikipedia, Di-tert-butyl dicarbonate (density 0.95 g/cm3, mp 22-24 C, bp 56-57 C at 0.5 mmHg; decomposition to tert-butanol, isobutene and CO2; production routes)",
      "url": "https://en.wikipedia.org/wiki/Di-tert-butyl_dicarbonate"
    },
    {
      "title": "PubChem CID 90495, Di-tert-butyl dicarbonate (identity: C10H18O5, InChIKey DYHSDKLCOJIUFX-UHFFFAOYSA-N)",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/90495"
    },
    {
      "doi": "10.1002/9783527621606",
      "title": "Stoessel, F. (2008) Thermal Safety of Chemical Processes, Wiley-VCH (accumulation, MTSR and the criticality classes of a semi-batch; method reference, not data)"
    }
  ],
  "repository": {
    "access": "public",
    "path": "processes/di-tert-butyl-dicarbonate-1",
    "url": "https://github.com/ChemE-as-Code/process-library"
  },
  "representations": [
    {
      "bytes": 56763,
      "id": "BFD",
      "kind": "bfd",
      "preview": "artifacts/di-tert-butyl-dicarbonate-1/BFD.svg",
      "source": "process/BFD.xml",
      "status": "preview",
      "title": "Block flow diagram"
    },
    {
      "bytes": 248138,
      "id": "PFD",
      "kind": "pfd",
      "preview": "artifacts/di-tert-butyl-dicarbonate-1/PFD.svg",
      "source": "process/PFD.xml",
      "status": "preview",
      "title": "Process flow diagram"
    },
    {
      "id": "process-model",
      "kind": "process-model",
      "source": "process/flowsheet.yaml",
      "status": "viewer",
      "title": "Flowsheet and stream table"
    },
    {
      "id": "equipment-list",
      "kind": "equipment-list",
      "source": "equipment/equipment-list.yaml",
      "status": "viewer",
      "title": "Equipment list"
    },
    {
      "id": "lca",
      "kind": "lca",
      "source": "lca/lca.yaml",
      "status": "viewer",
      "title": "Life cycle assessment"
    }
  ],
  "summary": "A batch plant: potassium tert-butoxide in recovered hexane takes up CO2 and then phosgene in one semi-batch at 278 K (CO2 vented to a caustic scrubber); the hexane is stripped and recycled, the Boc2O melt washed and distilled under vacuum from a paraffin heel. Concept stage, 655.71 kg per batch every 10.39 h, preliminary gate-to-gate LCI.",
  "title": "Di-tert-butyl dicarbonate by semi-batch carbonation and phosgenation of potassium tert-butoxide (500 t/a)",
  "validation": {
    "notes": "Concept batch PFD with closed mass, component and element balances (cheme validate: 5 blocks, 18 steps). The streams are calculated by cheme process propagate from the feeds: the semi-batch R101 from its ASSUMED rate laws with the CO2 and isobutene vented and both gas doses partly or wholly taken up with their ASSUMED heats of solution (core ADRs 0054, 0063), its vent saturated with the slurry's hexane and phosgene and passing R-101's vent condenser at 263 K (core ADR 0062), the degassing DG101 (a nitrogen sweep at 30 kPa(a)) at ASSUMED constant volatilities, its gas carrying the hexane that saturates the sweep past the vent condenser (core's vent and still carry no sweep gas), the strips ST101, ST102 and the vacuum still ST301 on Raoult's law with NIST Antoine constants and an ASSUMED line for Boc2O (core ADR 0055), ST101 with its charge's heat-up (ADR 0063), the scrubber S101 a conversion step; the recovered hexane S30 and the paraffin heel S22 are tears converged by propagate (core ADR 0060). The wash DC201 and the vent split X401 are specified splits from scripts/balance.py (no liquid-liquid or gas-liquid separator in core's propagate), outside any recycle, as are the duties the models leave out (the stills' sensible rise and vessel steel, condensers, the evaporator, the scrubber). The feeds are sized for 500 t/a (scaled to the product). The recipe takes the dosing, post-reaction, degassing, strip and distillation times from the models and the cool-down from the jacket, and sizes R-101, V-201 and C-301 (cheme process recipe, no cheme.recipe-basis finding). Thermal screening (cheme process reactor-hazards): R101 dT_ad 40.5 K (with the doses' heats of solution), accumulation 10.1 % (the deliberate CO2 excess; the phosgene's 2.7 % at the end of its dosing), MTSR 279.5 K against an MTT of 333.15 K (hazard.mtt, Boc2O's decomposition limit); the largest cooling-failure gas over the batch 24.5 m3/h with its vapour against an ASSUMED vent capacity of 50 m3/h; no criticality class without a TD24 (never estimated). The kinetics are assumed: at k/10 the MTSR is 282.5 K and the gas 26.6 m3/h, at k/100 292.0 K and 52.9 m3/h, 1.06 times the vent, with 36.1 % of the phosgene accumulated and stripped into that gas at up to 5.5 kg/h (y = x p*(T)/P over the cooling profile; 0.11 kg/h at the design rate) (a design finding: dosing interlocks, the scrubber's caustic inventory, relief from calorimetry, DESIGN.md D-014). Preliminary gate-to-gate LCI with nitrogen as a per-batch consumable; potassium tert-butoxide, phosgene, caustic soda and nitrogen linked to potassium-tert-butoxide-1, phosgene-1, chlor-alkali-1 and asu-1, hexane, DABCO, CO2 and the paraffin gaps. Not reviewed. Needs cheme-as-code 1.10.0 (DESIGN.md D-015).",
    "status": "unreviewed"
  },
  "viewer": {
    "commit": "a3c52e472f42fbc8cdacfeacf5ef28703c004174",
    "dirty": false,
    "sheets": [
      "process/BFD.xml",
      "process/PFD.xml"
    ],
    "skipped": [],
    "snapshot": "snapshots/di-tert-butyl-dicarbonate-1/",
    "stale": false,
    "tool": "cheme-as-code 1.6.0",
    "views": [
      "checks"
    ]
  }
}