This work reports a study on the reactivity of polymeric carbon nitride (PCN) and PCN-H₂O₂ adduct samples for sunlight photocatalytic selective oxidation reactions. The characterization of these materials was reported in a previous paper where the reactivity towards the partial oxidation of 5-hydroxymethylfurfural (HMF) was studied by using two different laboratory scale photoreactors; one irradiated by UV lamps and the other one by natural sunlight. In the present study it has been confirmed the effectiveness of these C₃N₄ based materials for the selective partial oxidation of HMF to FDC (2,5-furandicarboxaldehyde) in aqueous medium in a pilot plant photoreactor irradiated by natural sunlight. The reactivity results and, in particular, the selectivity to FDC formation have been very encouraging, mostly by considering that the reaction was carried out in water. Moreover, they are comparable with those obtained in the laboratory scale photoreactors irradiated by both UV lamps and natural sunlight. Interestingly, the pristine PCN sample has shown a higher HMF conversion with respect to that of the PCN-H₂O₂ adduct, but the last one is more selective to the FDC formation. A kinetic study indicates that the pseudo-first-order rate constant of HMF oxidation is higher in the case of pristine photocatalyst and that the equilibrium adsorption constants of HMF is higher in the case of PCN-H₂O₂ adduct catalyst. Finally, the partial oxidation of two aromatic alcohols, i.e. benzyl alcohol (BA) and 4-methoxy benzyl alcohol (4-MBA) to benzaldehyde (BAL) and 4-methoxy benzaldehyde (4-MBAL), respectively, has also been studied.

这项工作报告了对聚合碳氮化物（PCN）和PCN-H ₂ O ₂加合物样品对日光光催化选择性氧化反应的反应性的研究。在先前的一篇论文中报道了这些材料的特性，该论文通过使用两种不同的实验室规模的光反应器研究了对5-羟甲基糠醛（HMF）部分氧化的反应性。一种是用紫外线灯照射，另一种是用自然阳光照射。在本研究中，已经证实了这些C ₃ N ₄的有效性基材料，用于在自然光照射下的中试植物光反应器中，在水性介质中将HMF选择性部分氧化为FDC（2,5-呋喃二甲醛）。反应性的结果，尤其是对FDC形成的选择性非常令人鼓舞，主要是考虑到该反应是在水中进行的。而且，它们与在实验室规模的光反应器中通过紫外线灯和自然日光照射获得的光可比。有趣的是，原始PCN样品相对于PCN-H ₂ O ₂表现出更高的HMF转化率加合物，但最后一个对FDC的形成更具选择性。动力学研究表明，在原始光催化剂的情况下，HMF氧化的拟一级反应速率常数较高，在PCN-H ₂ O ₂加合物的情况下，HMF的平衡吸附常数较高。最后，两种芳族醇（即）的部分氧化。还研究了苯甲醇（BA）和4-甲氧基苯甲醇（4-MBA）分别形成苯甲醛（BAL）和4-甲氧基苯甲醛（4-MBAL）。