| Inhibitor | Concentration (M) | Weight Loss (mg) | Corrosion rate (mg・cm−2・hr−1) | Inhibition efficiency (IE%) |
| - | 0 | 27.52 | 3.44 | - |
| HPZ (1) | 0.63 × 10−4 1.25 × 10−4 2.5 × 10−4 5 × 10−4 | 16.00 14.40 12.80 7.20 | 2.0 1.8 1.6 0.9 | 42 48 53 74 |
| ACPHPZ (2) | 0.63 × 10−4 1.25 × 10−4 2.5 × 10−4 5 × 10−4 | 16.80 11.20 6.40 2.40 | 2.1 1.4 0.8 0.3 | 40 59 76 91 |
| ACTHPZ (3) | 0.63 × 10−4 1.25 × 10−4 2.5 × 10−4 5 × 10−4 | 10.40 8.80 5.60 2.00 | 1.3 1.1 0.7 0.25 | 62 68 80 93 |
| MFHPZ (4) | 0.63 × 10−4 1.25 × 10−4 2.5 × 10−4 5 × 10−4 | 18.40 15.20 12.80 8.00 | 2.3 1.9 1.6 1.0 | 33 45 53 71 |