# SAT-HM-001 - Homemade SAT Process Rehearsal

Status: Approved plan, not yet performed  
Date issued: 2026-08-13  
Owner and approval authority: Tristan  
Purpose: Rehearse neutralization, filtration, concentration, and crystallization using household-grade materials.

This batch is exploratory and nonqualified. Material recovered from it must not
be used as the pure-SAT control or in the formal nucleator matrix.

## Formula and bounds

Reaction:

`Na2CO3 + 2 CH3COOH -> 2 CH3COONa + CO2 + H2O`

| Item | Nominal quantity |
|---|---:|
| Windsor House 10% v/v cleaning vinegar | 100.0 mL |
| Anhydrous sodium-carbonate equivalent | 9.26 g |
| Sodium-carbonate monohydrate equivalent | 10.83 g |
| Theoretical anhydrous sodium acetate | 14.33 g |
| Theoretical SAT at ideal hydration | 23.77 g |

The carbonate mass is guidance, not the endpoint. Washing-soda assay, moisture,
and hydration are unknown. The operational endpoint is approximately pH 8-9
after carbon-dioxide evolution has subsided. Never exceed 10.85 g carbonate.

## Required equipment

- clean 500 mL or larger borosilicate beaker for neutralization and later water bath;
- clean 250 mL borosilicate beaker for filtrate and concentration;
- graduated cylinder suitable for measuring 100.0 mL;
- scale resolving 0.01 g;
- clean PTFE-coated magnetic stir bar and glass stirring rod;
- SH-2 magnetic stirrer/heater;
- DMM thermocouple in the documented PTFE U-tube sheath;
- universal pH paper, clean transfer rod, coffee filter, and funnel;
- distilled or deionized water and a watch glass;
- clamps, secondary containment, eye protection, and gloves.

Do not begin until Rochelle-salt material has been removed and both beakers,
the stir bar, watch glass, glass rod, graduated cylinder, and filtration
equipment have been washed, distilled-water rinsed, dried, and inspected.

## Preflight

1. Record the dry mass of the 250 mL beaker plus stir bar to 0.01 g.
2. Form the PTFE tube into a broad U without flame. Place the thermocouple bead
   at the bend and keep both open ends above any liquid.
3. Leak-test the sheath. Perform ice-water and hot-water sanity checks and
   record the readings and 90% response time.
4. Using plain water, test whether the SH-2 couples to the stir bar through the
   proposed two-beaker water bath. If it decouples, plan on manual glass-rod
   stirring during concentration.
5. Confirm that the vinegar is reported to contain only water and acetic acid.
   Stop if fragrance, surfactant, persistent foam, oil, or unexpected colour is
   observed.

## Neutralization

1. Measure 100.0 mL vinegar and transfer it to the open 500 mL beaker.
2. Work unheated with ventilation and secondary containment. Start gentle
   stirring.
3. Add 7.50 g sodium carbonate in 0.50 g portions. Wait for foaming to subside
   after every portion.
4. Continue to 8.50 g total using 0.25 g portions.
5. Stir for five minutes, then wait for residual gas evolution to settle.
6. Transfer one drop with the clean glass rod to universal pH paper. Never dip
   the paper into the batch.
7. If below pH 8, add 0.10 g portions. Allow complete reaction and repeat the
   five-minute stir/settle step before every pH test.
8. Stop at approximately pH 8-9. Stop additions immediately above pH 9.
9. If pH remains below 8 at 10.85 g total carbonate, stop and classify the run
   as an endpoint failure. Do not add more unknown-grade carbonate.

## Filtration

1. Rinse the coffee filter with distilled water and discard the rinse.
2. Gravity-filter into the pre-weighed 250 mL beaker containing its stir bar.
3. Do not squeeze the filter and do not rinse the retained solids into the batch.
4. Record filtrate appearance and the initial net filtrate mass.
5. Stop and quarantine on persistent foam, fragrance, oily film, strong colour,
   or unexpected insoluble material.

## Concentration

1. Clean the 500 mL beaker and use it as the outer water bath.
2. Place and clamp the 250 mL beaker inside it. Prevent glass-to-glass contact
   and keep bath water near the product-liquid level without risk of ingress.
3. Immerse the PTFE U-bend near product mid-depth, clear of the beaker, bottom,
   and stir bar. Keep both tube openings above the liquid.
4. Heat at low power and maintain approximately 80-85 C indicated. Wait at
   least the measured probe response time before adjusting heater power.
5. Do not allow vigorous boiling, bath boil-dry, or unattended operation.
6. If magnetic coupling fails, disable magnetic stirring and stir manually at
   least every two minutes and before trusting a temperature reading.
7. For each weighing: switch off heat, remove the inner beaker, wipe its outside
   completely dry, cool it below 40 C, and weigh it. Never place hot glass on
   the scale.

## Staged crystallization endpoint

1. Stop first at `25.0 +/- 0.1 g` net batch mass.
2. Loosely cover with the watch glass and cool undisturbed at room temperature
   for 24 hours.
3. If no crystals appear, reheat and repeat at 24.5 g, 24.0 g, and finally
   `23.8 +/- 0.1 g`.
4. Record the time and temperature of the first visible crystallization.
5. Do not introduce salt, graphite, nucleators, or foreign seed material.
6. Do not intentionally concentrate below 23.7 g. After a minor overshoot, cool
   and restore the batch to 23.8 g using distilled water dropwise; record the
   added mass.
7. Stop and quarantine after scorching, cracked glass, contamination,
   uncontrolled boiling, or net batch mass below 23.0 g.

## Outcome classification

- **Process pass with crystals:** all controlled steps succeeded and identifiable crystals formed.
- **Process pass without crystals:** equipment and mass control succeeded, but crystallization did not occur.
- **Endpoint failure:** acceptable pH was not reached within 10.85 g, or pH overshot above 9.
- **Contamination/equipment failure:** unexpected additives, residue, unsafe heating, loss of control, or probe failure occurred.

Label every recovered container:

`SAT-HM-001 - exploratory, nonqualified - DO NOT USE AS CONTROL`

## Batch record

### Materials

| Field | Record |
|---|---|
| Vinegar product and lot | |
| Vinegar label claim | 10% acetic acid by volume |
| Washing-soda product and lot | |
| Washing-soda label claim | Sodium carbonate, washing grade |
| Source-image directory | `Chemistry/Images/SAT-HM-001/` |

### Equipment preflight

| Field | Record |
|---|---|
| 250 mL beaker + stir-bar tare | g |
| Ice-water indication | C |
| Hot-water indication and test condition | C |
| Sheathed-probe 90% response time | s |
| Magnetic coupling through bath | Pass / Fail |
| Manual stirring required | Yes / No |

### Reaction and filtration

| Field | Record |
|---|---|
| Actual vinegar volume | mL |
| pH after 8.50 g carbonate | |
| Final carbonate mass | g |
| Final pH after settling | |
| Filtrate net mass | g |
| Filtrate colour/clarity/residue | |

### Concentration and cooling

| Stage | Net mass | Peak indicated temperature | Start time | Crystals after 24 h | Notes |
|---|---:|---:|---|---|---|
| 1 | 25.0 g target | C | | Yes / No | |
| 2 | 24.5 g target | C | | Yes / No | |
| 3 | 24.0 g target | C | | Yes / No | |
| 4 | 23.8 g target | C | | Yes / No | |

| Final field | Record |
|---|---|
| First crystallization time and temperature | |
| Crystallization classification | Spontaneous / handling-induced / deliberately seeded / absent |
| Distilled-water correction | g |
| Recovered product mass | g |
| Outcome classification | |
| Photo locations | |
| Deviations and failures | |
| Tristan disposition | Retain / repeat / discard / advance to purification planning |

## References

- Source-material evidence and sheath note: `Chemistry/Images/SAT-HM-001/README.md`
- SAT route programme: `Chemistry/SAT/NanoArc_SAT_Crystallization_Route_Plan_Rev0.md`
- Formal stock-intake gate: `Chemistry/SAT/SAT_STOCK_QUALIFICATION.md`
- Reference retrieval gaps: `Chemistry/References/REFERENCE_GAPS.md`
- SAT phase behaviour: A. Safari et al., *CrystEngComm* 23 (2021), DOI `10.1039/D0CE01454K`.