In this study, we describe the development of a hybrid bioreactor with integrated chlorinated polyethylene (CPE) fixed-bed and zeolite as a microorganism nutrition carrier (MNC), aiming at enhancing and sustaining biohydrogen production during the anaerobic digestion (AD) process. In the batch test, the hybrid bioreactor achieved a maximum biohydrogen production of 646.3 mL/L. Accordingly, the hybrid bioreactor significantly enhanced biohydrogen production and maintained a stable performance for 50 days of semi-continuous operation. This result should be attributed to the CPE providing roughness surface and high porosity for microorganism immobilization, resulting in the enhancement of microbial quantity, confirmed by our scanning electron microscope and immobilized biomass analyses. Moreover, the element ratio significantly decreased, indicating that zeolite could provide metal cations for stimulating microbial bioactivity and growth, as well as contributing to superior biohydrogen productivity during the 50-day operation. In order to further enhance and sustain long-term biohydrogen production, raw zeolite was modified with iron. The hybrid-Fe bioreactor (CPE with Fe-modified zeolite) operated mainly following the acetate pathway and exhibited higher sustainability in improving biohydrogen production with a peak value of 1893.0 mL/L during a 72-day-lasting operation. The synergistic mechanism of the Fe-modified zeolite and CPE fixed-bed revealed that it could effectively induce favorable pathways and contribute to the synthesis of essential enzymes, micronutrient supplementation, electoral conductivity, and microbial immobilization for biohydrogen production. Therefore, a hybrid-Fe bioreactor could provide a unique alternative for the enhancement of hydrogen production for practical applications.

在这项研究中，我们描述了一种混合生物反应器的开发，该反应器具有集成的氯化聚乙烯（CPE）固定床和沸石作为微生物营养载体（MNC），旨在增强和维持厌氧消化（AD）过程中生物氢的产生。在分批测试中，混合生物反应器的最大生物氢产量为646.3 mL / L。因此，该杂化生物反应器显着提高了生物氢的产生并在半连续操作的50天中保持了稳定的性能。该结果应归因于CPE为微生物固定化提供了粗糙的表面和高孔隙率，从而导致微生物数量的增加，这由我们的扫描电子显微镜和固定化的生物量分析证实。而且，元素比例显着下降，这表明沸石可以提供金属阳离子以刺激微生物的生物活性和生长，并在50天的操作过程中有助于提高生物氢生产率。为了进一步提高和维持长期的生物氢生产，用铁对粗沸石进行了改性。杂化铁生物反应器（含铁改性沸石的CPE）主要遵循乙酸盐途径运行，在持续72天的操作过程中，在提高生物氢产量方面表现出更高的可持续性，峰值为1893.0 mL / L。铁修饰的沸石和CPE固定床的协同作用机理表明，它可以有效地诱导有利的途径，并有助于合成必需的酶，补充微量营养素，提高电导率和固定化微生物以生产生物氢。因此，