Mixed xylenes (with ethylbenzene)

Activity Benzene, toluene and mixed xylenes by solvent extraction of catalytic reformate, RER: the inventory of 1 kilogram of its reference product, attributional, cut-off.

Calculation maturity: not assessed Design maturity: Concept (research)Not independently reviewedbtx-1:btx-reformate-extraction:product:xylenesPreliminaryReport a problem with this dataset

Research outputAn inventory from a research design at the design maturity its process states, not verified plant data: check its calculation maturity and review status before use. Background activities are referenced by name only; no background data is included. All caveats

What it is

Per 1 t of benzene, toluene and mixed xylenes together, gate-to-gate. Reformate split, sulfolane-type extraction, clay treatment and benzene, toluene and xylene columns. Raffinate and C9+ aromatics are co-products. Feed slate from one typical US reformate, utilities as midpoints of the EU LVOC BREF ranges for BTX extraction units.

Reference product: 1 kilogram of Mixed xylenes (with ethylbenzene)
Chemical: xylenes
CAS: 1330-20-7
Code: btx-1:btx-reformate-extraction:product:xylenes
Dataset: btx-reformate-extraction version 0.1.0 · UUID 2a5d3064-9e1d-514b-93af-bbad46f28a1f
Activity UUID: not available (the library assigns none; use the code)
Database: cheme-as-code-atlas-preview-a3c52e4 (version preview-a3c52e4)
Process: Benzene, toluene and mixed xylenes by solvent extraction of catalytic reformate
Geography: RER · background inputs with a site rule link at the user's site location (default DE)
Time period: 1999 · valid until 2017
Technology: liquid-liquid or extractive-distillation extraction with sulfolane-type solvent, clay treatment, distillation; para-xylene recovery, isomerisation, toluene conversion and pygas feed are not modelled · level current
Boundary: gate-to-gate: reformate splitting (mass balance only), aromatics extraction with solvent recovery, clay treatment, benzene, toluene and xylene fractionation; steam, fuel heat and power from outside
Classification: ISIC Rev.4 1920, 2011 (taxonomy/families.yaml (ISIC Rev.4) of the process's families)
System model: attributional, cut-off (docs/system-model.md, methodology 1.1.0)
Allocation: mass, 25.6 % of the dataset to this product (rule deviation, from dataset)
No sourced prices, so the WBCSD price ratio of the five co-products cannot be computed. Raffinate and C9+ aromatics are gasoline components, but the aromatics have energy content too, so an energy rule is not clearly the physical relationship. Mass is the preliminary choice.
Rights: CC-BY-4.0

Exchanges per 1 kilogram of Mixed xylenes (with ethylbenzene)

As exported: allocated and scaled to the reference product. Provenance: 1 calculated, 1 assumed, 7 given. Pedigree scores (1 best, 5 worst): reliability, completeness, temporal correlation, geographical correlation, further technological correlation.

Preliminary3 exchanges are not yet linked to a background dataset. They count no burden, so the inventory is incomplete: do not read a result from it as complete.

Input	Amount	Unit	Provenance	Pedigree	Linked to
Catalytic reformate (debutanised, C5+) feed:reformate the basis over the recovered aromatics fraction of the reformate (DOE 2000 Table 4-1 with the recoveries); the removal of the C9+ cut is in the boundary by mass only (its splitter energy is a TODO exclude)	1	kilogram	calculated	4 4 5 4 4	Atlas (pinned): Catalytic reforming of naphtha with continuous catalyst regeneration (CCR) (Reformate, C5+ (stabilised), RER) compatible: grade the input names reformate only; reformate (Reformate, C5+ (stabilised)) is taken; unit kilogram; system model cutoff (one database); allocation energy (physical-energy); boundary plant gate (pinned): no distribution or losses; the consumer's dataset counts its delivery
Water to the process (dissolved in the feed and the wet solvent loop) feed:water ASSUMED equal to the water drained (output:wastewater), so that the water balance closes	1.806e-4	kilogram	assumed	4 4 4 4 4	market for water, deionised (water, deionised, RoW) in your background (default ecoinvent-3.11-cutoff)
Electricity feed:electricity EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, Table 4.3, p. 217 (BB2) electricity	0.02498	kilowatt hour	given	3 4 4 3 3	market for electricity, medium voltage (electricity, medium voltage, DE, site location) in your background (default ecoinvent-3.11-cutoff)
Steam, as heat delivered feed:steam EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, Table 4.3, p. 217 (BB2); gross, heat recovery and heat integration with other units not credited	0.3471	kilowatt hour	given	3 4 4 3 3	Atlas: heat from steam, per kWh (Atlas unit proxy) (heat from steam, by energy, GLO)
Fired heat from fuel (reboilers), as heat from natural gas feed:fuel-heat EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, Table 4.3, p. 217 (BB2); the fuel (fuel gas or natural gas, not named) is counted as heat from natural gas, whose background includes the combustion (ASSUMED), so no flue gas is listed here heat, fired reboilers	0.3082	kilowatt hour	given	4 4 4 4 4	Atlas: heat from natural gas, industrial furnace, per kWh (Atlas unit proxy) (heat from natural gas, by energy, GLO)
Clay for the clay treaters (make-up) input:clay EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, Table 4.5, p. 219 (spent clay of BB2, taken as the make-up, ASSUMED); mass outside the element balance	2.27e-4	kilogram	given	3 4 4 3 3	unlinked unlinked, no technosphere mapping: no mapping (chemical 'clay'); add it to lci/mappings.yaml technosphere or to the process's lca/mappings.yaml exchanges
Spent clay, to external disposal or incineration output:spent-clay EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, Table 4.5, p. 219, and 4.3.6.3 (its fate); hydrocarbons held on the clay not counted; mass outside the element balance	2.27e-4	kilogram	given	3 4 4 3 3	unlinked unlinked, no technosphere mapping: no mapping (no chemical slug or factor id); add it to lci/mappings.yaml technosphere or to the process's lca/mappings.yaml exchanges
Solvent-regenerator sludge, to disposal output:solvent-sludge EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, section 4.3.6.4, p. 219 (gums, solvent degradation products, scale, some solvent); mass outside the element balance	1.595e-5	kilogram	given	3 4 4 3 3	unlinked unlinked, no technosphere mapping: no mapping (no chemical slug or factor id); add it to lci/mappings.yaml technosphere or to the process's lca/mappings.yaml exchanges
Water drained to wastewater treatment output:wastewater EU JRC (2017) LVOC BREF, EUR 28882 EN, doi:10.2760/77304, section 4.3.2.2, p. 215; may hold BTX and solvent (not counted)	1.806e-4	kilogram	given	4 4 4 4 4	Atlas (plant): wastewater to treatment, per kg (Atlas unit proxy) (wastewater, by mass, GLO) compatible: grade the input names wastewater only; wastewater (Wastewater treated) is taken; unit kilogram; system model cutoff (one database); allocation mass (single-output); boundary plant gate of a site utility: no utility market yet (docs/markets.md)

Elementary flows

No elementary flows are exported for this activity (pass-through emissions and free inputs are left out, see the caveats).

Where these numbers come from: each exchange names its source above; the dataset is processes/btx-1/lca/datasets/btx-reformate-extraction.yaml in library version a3c52e4.

Used by

No other activity of this database links to it.

How good it is

Review: Not reviewed: no LCI review record yet
Data quality: not available
Mass and carbon closure: Not available: a hand-written dataset: no lca/manifest.json records its balance
Change report: Not available: this build has no change report against an earlier release.

KPI benchmark positions

KPI	Value	Reference range	Position
Electricity per t of benzene, toluene and xylenes extracted	– kWh/t	11 to 72 kWh/t Falcke, H. et al. (2017) Best Available Techniques (BAT) Reference Document for the Production of Large Volume Organic Chemicals. JRC Science for Policy Report EUR 28882 EN, doi:10.2760/77304 (bref)	not evaluated
Electricity, steam and fired heat per t of benzene, toluene and xylenes extracted	– kWh/t	633 to 1,564 kWh/t Falcke, H. et al. (2017) Best Available Techniques (BAT) Reference Document for the Production of Large Volume Organic Chemicals. JRC Science for Policy Report EUR 28882 EN, doi:10.2760/77304 (bref)	not evaluated

How to use it

Downloads

cheme-as-code-atlas-preview-a3c52e4.xlsx · bw2io ExcelImporter workbook (bw2io 0.9 Excel layout) · the whole database
code btx-1:btx-reformate-extraction:product:xylenes
cheme-as-code-atlas-preview-a3c52e4-olca-jsonld.zip · openLCA JSON-LD (olca-schema) (2) · the whole database
process 2a5d3064-9e1d-514b-93af-bbad46f28a1f (processes/2a5d3064-9e1d-514b-93af-bbad46f28a1f.json) · the dataset's unallocated multi-output process; this product's allocation factor is in it
cheme-as-code-atlas-preview-a3c52e4-multifunctional.json · Brightway 2.5 multifunctional database (JSON, for the multifunctional package) (cheme-as-code/lci-multifunctional/v1) · the whole database
code btx-1:btx-reformate-extraction · the dataset unallocated, with all its products; this product is its desired_code
cheme_as_code_lci-0.1.0-py3-none-any.whl · the installer

A file with this activity alone is not available: each file above is the whole database, and the line under it says how to find this activity there.

import bw2data as bd
from cheme_as_code_lci import install

bd.projects.set_current("my-project")   # holds your licensed background + biosphere3
install("cheme-as-code-atlas-preview-a3c52e4.xlsx", background="ecoinvent-3.11-cutoff", location="DE")
activity = bd.get_activity(("cheme-as-code-atlas-preview-a3c52e4", "btx-1:btx-reformate-extraction:product:xylenes"))

While any exchange of the database has no mapping, install() writes nothing and only lists the unlinked exchanges. So the last line finds no activity until the gaps are mapped: the download section gives the ways to use the database now.

How to cite

Mixed xylenes (with ethylbenzene), from Benzene, toluene and mixed xylenes by solvent extraction of catalytic reformate (dataset btx-reformate-extraction 0.1.0), ChemE-as-Code Process Atlas LCI database preview-a3c52e4, activity btx-1:btx-reformate-extraction:product:xylenes. Cite the Process Atlas paper (in preparation, 2026), by Artur M. Schweidtmann and Jana M. Weber, and the ChemE-as-Code Process Atlas LCI database version preview-a3c52e4.

DOI: none yet (the Process Atlas paper is in preparation)

For the data, cite the Process Atlas paper; for the platform that builds and checks it, the ChemE-as-Code paper.

Schweidtmann, A. M. & Weber, J. M. (2026, in preparation). Process Atlas: an open, git-native, reproducible library and life cycle inventory of chemical processes (working title).

BibTeX

@unpublished{schweidtmann_process_atlas,
  author = {Schweidtmann, Artur M. and Weber, Jana M.},
  title = {{Process Atlas: an open, git-native, reproducible library and life cycle inventory of chemical processes (working title)}},
  year = {2026},
  url = {https://atlas.cheme-as-code.org},
  note = {in preparation}
}

Schweidtmann, A. M. (2026). ChemE-as-Code: An Open-Source Platform for Agentic AI in Chemical Engineering. arXiv:2611.07947. https://doi.org/10.48550/arXiv.2611.07947

BibTeX

@misc{schweidtmann_cheme_as_code,
  author = {Schweidtmann, Artur M.},
  title = {{ChemE-as-Code: An Open-Source Platform for Agentic AI in Chemical Engineering}},
  year = {2026},
  eprint = {2611.07947},
  archivePrefix = {arXiv},
  doi = {10.48550/arXiv.2611.07947},
  url = {https://arxiv.org/abs/2611.07947}
}