Urine, which is an important waste biomass resource, is the main source of nitrogen in sewage and contains large quantities of emerging contaminants (ECs). In this study, we propose a new method to efficiently remove urine, simultaneously eliminate ECs, and control the generation of toxic chlorate during urine treatment using a photoelectrocatalytic-chlorine (PEC-Cl) system. A type-II heterojunction of WO₃/BiVO₄ was used as a photoanode to generate chlorine radicals (Cl•) by decreasing the oxidation potential of WO₃ valence band for the highly selective conversion of urine to N₂ and the simultaneous degradation of ECs in an efficient manner. The method presented surprising results. It was observed that the amount of toxic chlorate was significantly inhibited by circumventing the over-oxidation of Cl^- by holes or hydroxyl radicals (•OH). Moreover, the removal of urea nitrogen reached 97% within 90 min, while the degradation rate of trimethoprim in urine was above 98.6% within 60 min, which was eight times more than that in the PEC system (12.1%). Compared to the bare WO₃ photoanode, the toxic chlorate and nitrate generated by the WO₃/BiVO₄ heterojunction photoanode decreased by 61% and 44%, respectively. Thus, this study provides a safe, efficient, and environmentally-friendly approach for the disposal of urine.

尿液是重要的废物生物质资源，是污水中氮的主要来源，并含有大量的新兴污染物（EC）。在这项研究中，我们提出了一种新方法，该方法可使用光电催化氯（PEC-Cl）系统有效地去除尿液，同时消除EC，并控制尿液处理过程中有毒氯酸盐的产生。WO ₃ / BiVO ₄的II型异质结被用作光阳极，通过降低WO ₃价带的氧化电势以将尿液高度选择性地转化为N ₂来产生氯自由基（Cl•）。并以有效方式同时降解EC。该方法给出了令人惊讶的结果。据观察，有毒氯酸盐的量显著绕开Cl组成的过氧化抑制^-通过孔或羟基自由基（•OH）。此外，尿素氮的去除率在90分钟内达到97％，而甲氧苄啶在60分钟内的降解率则达到98.6％以上，是PEC系统（12.1％）的八倍。与裸WO ₃光电阳极相比，WO ₃ / BiVO ₄产生的有毒氯酸盐和硝酸盐异质结光阳极分别减少了61％和44％。因此，这项研究为尿液的处理提供了一种安全，有效和环保的方法。