An Innovative Process for the Recovery of Consumed Acid in Rare-Earth Elements Leaching from Phosphogypsum
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Many technologies relied upon by modern society, such as portable electronics and renewable energy systems, require the use of rare-earth elements (REEs). The global demand for REEs is increasing rapidly, and new developments for their recovery from secondary sources have been sparked. Phosphogypsum (PG), the byproduct of phosphoric acid production, is considered a secondary source for REEs. This research builds upon previous studies investigating the hydrometallurgical recovery of REEs from PG via acid leaching. The current study put the emphasis on developing processes to recover consumed acid in the leaching process. Here we propose an innovative process that relies upon the addition of calcium sulfate anhydrite seeds to the leached solution. Anhydrite seeding results in the rejection of calcium sulfate from the leached solution and reduced calcium concentration. Because the REE leaching efficiency is controlled by the solubility limit of PG, which is correlated to the calcium concentration, the drop increases the potential of the solution to leach more REEs. Thus, the solution can be recycled and reused as the leachant in subsequent leaching steps. This novel process is a promising technique to recycle consumed acid, lowering the operating costs and improving the efficiency.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it