Lignin depolymerisation produces a large variety of low molecular weight phenolic compounds that can be upgraded to value-added chemicals. Detailed analysis of these complex depolymerisation mixtures is, however, hampered by the lack of resolving power of traditional analysis techniques. In this study, a novel online comprehensive two-dimensional reversed-phase liquid chromatography (RPLC) × supercritical fluid chromatography (SFC) method with trapping column interface was developed for the separation of phenolic compounds in depolymerised lignin samples. The trapping capacities of different trapping columns were evaluated. The influence of large volume water-containing injection on SFC performance was studied. The relation between peak capacity and first dimension flow rate and gradient was investigated. The optimized method was applied for the analysis of a depolymerised lignin sample. The RPLC × SFC system exhibited high degree of orthogonality. Compared with traditional loop based interface, trapping column interface can significantly shorten the analysis time and offer higher detectability, with the disadvantage of more severe undersampling in the first dimension.

木质素解聚可产生多种低分子量酚化合物，可将其升级为增值化学品。但是，由于缺乏传统分析技术的分辨能力，因此无法对这些复杂的解聚混合物进行详细分析。在这项研究中，开发了一种新型的在线综合二维反相液相色谱法（RPLC）×超临界流体色谱法（SFC），该方法具有捕集柱界面，用于分离解聚木质素样品中的酚类化合物。评价了不同捕集柱的捕集能力。研究了大体积含水注射液对SFC性能的影响。研究了峰容量与一维流速和梯度之间的关系。优化后的方法用于分析解聚的木质素样品。RPLC×SFC系统表现出高度的正交性。与传统的基于环的接口相比，捕集柱接口可以显着缩短分析时间并提供更高的可检测性，其缺点是一维欠采样更加严重。