Table 4. Comparison of the Efficiency of Synthesized Adsorbent with Previously Reported Adsorbents.
| adsorbent | adsorbent dose (g/L) | fluoride concentration range (mg/L) | adsorbent capacity (mg/g) | pH | ref |
|---|---|---|---|---|---|
| regenerated spent bleaching earth | 10 | 2.5–8 | 0.6 | 7 | (56) |
| quick lime | 5 | 10–100 | 9.7 | (53) | |
| synthetic nano HAp | 4 | 3–80 | 4.575 | 5–6 | (57) |
| HAp | 20 | 3–80 | 1.432 | 5 | (58) |
| nanosized HAp | 0.2 | 50 | 3.44 | 5 | (59) |
| cellulose@hydroxyapatite nanocomposites | 4 | 10 | 4.2 | 6.5 | (60) |
| Al-modified hydroxyapatite (Al-HAP) | 0.5 | 5–50 | 32.57 | 7 | (61) |
| nHAp derived from PG | 1 | 10–50 | 19.74–40.81 | 2–11 | (62) |
| egg shell | 24 | 5 | 1.09 | 6 | (63) |
| commercial HAp | 8 | 2–15 | 1.76 | 6 | (64) |
| hydroxyapatite | 3 | 10 | 22.3 | 6 | the present study |