| Vendor | Spec | Unit | Price | Currency | Date |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 689.11 | USD | 20250922 |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 688.9 | USD | 20250919 |
| Qingdao Chengxin Hongfeng Chemical Co., Ltd. | China national standards | MT | 689.32 | USD | 20250918 |