Batches with free acid < 0.5 (from structured records):

| Batch | Free acid | Step-1 time |
|---|---|---|
| 48 (LBN 48 / S 9076 #48) | 0.24 | 5 hrs (58–75 °C) |
| 48 Q (LBN 48 Q) | 0.24 | 5 hrs |
| 24 C | 0.3 | 0.5 + 4.5 h |
| 24 CR | 0.3 | 0.5 + 4.5 h |
| 24 CR2 | 0.25 | 0.5 + 4.5 h |
| 25 A (Lab Batch 25 A) | 0.42 | step-1 4.5 h (55–60 °C) |
| 25 I | 0.29 | 4.5 h (55–60 °C) |
| 50 (50 A / 50 B) | 0.1 | step-2 0.2 h @ 80 °C |

Not below 0.5: 30 (0.66), 49 (1.096), 51 (0.837).

Caveats on "after how long": these free-acid values are step-1/step-2 end-of-step readings in each record, not a free-acid-vs-time curve. No record tracks free acid crossing 0.5 as a function of reaction time, so the elapsed time shown is the step duration at which the value was measured, not a "time to drop below 0.5." (For reference, an earlier notebook entry — "9076 Exp 48-60_1" p11 — shows free Acid 0.75 at ~5 hrs for an analogous step-1, but that record is not linked to a confirmed batch.)