<p>The implementation of the nonradical (¹O₂) pathway in conventional Fenton reactions is a promising approach for degrading organic pollutants in water. In this study, a one-step co-pyrolysis method of red mud (RM) and spent coffee grounds (SCG) was employed to prepare an iron-rich catalyst (RMSCG70) for activating H₂O₂ in a photo-Fenton system to degrade tetracycline hydrochloride (TCH). RMSCG70 exhibited excellent TCH degradation performance under visible-light irradiation. At a catalyst dosage of 0.1 g/L, H₂O₂ concentration of 3 mmol/L, and TCH concentration of 20 mg/L, the TCH removal rate reached 99.3% within 60 min. Quenching experiments conducted under the light and dark conditions, together with Electron Paramagnetic Resonance (EPR) analyses, indicated that ¹O₂ is the main reactive oxygen species (ROS). The O<Stack> ₂ ^•− </Stack> generated by O₂ reduction reacted with the ^•OH_ads on the catalyst surface to form ¹O₂, and the FeAl₂O₄ component in RMSCG70 in the photo-Fenton system promoted the generation of O<Stack> ₂ ^•− </Stack> and ^•OH_ads. Cyclic experiments showed that the TCH degradation efficiency remained around 90% after five cycles. Further investigation of its application potential in a continuous-flow reactor revealed that when the hydraulic retention time (<i>t</i>_hr) was 30 min, the TCH removal rate reached approximately 80%. This study revealed the mechanism of organic pollutants under visible-light irradiation using RM and SCG as photocatalysts, while enabling the resource utilization of solid waste.</p>