Competition of Sulphation and Carbonation Reactions during Looping Cycles for CO<sub>2</sub> Capture by CaO-Based Sorbents
Bibliographic record
Abstract
Two types of sorbents are investigated here (natural limestone and highly reactive calcium aluminate pellets) to elucidate their reactivity in terms of sulphation and carbonation and determine the resulting effect on looping cycles for CO(2) capture. The sorbents are tested in a thermogravimetric analyzer (TGA) apparatus using typical synthetic flue gas mixtures containing 15% CO(2) and various concentrations of SO(2). The sulphation and carbonation conversions were determined during sulphation/carbonation/calcination cycles. The sorbent morphology and its changes were determined by means of a scanning electron microscope (SEM). The results showed that sulphation, that is, the formation of CaSO(4) at the sorbent surface, is a cumulative process with increasing numbers of reaction cycles, which hinders sorbent ability to capture CO(2). In the case of high sorbent reactivity, as determined by its morphology, the unfavorable effect of sulphation is more pronounced. Unfortunately, any increase in the temperature in the carbonation stage accelerates sulphation more than carbonation as a result of higher activation energy for the sulphation reaction. The SEM analyses showed that although sulphation and carbonation occur during cycles involving calcination, an unreacted core/partially sulphated shell sorbent particle pattern is formed. The main outcomes of this research indicate that special attention should be paid to the sulphation when more reactive and more expensive, synthetic CaO-based sorbents are used for CO(2) capture looping cycles. Desulphurization of flue gas before CO(2) capture appears to be essential because CO(2) looping cycles are so strongly affected by the presence of SO(2).
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.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".