A pressure tunable (PT) coupled column ensemble has been implemented for the second dimension (²D) separation in comprehensive two dimensional gas chromatography (GC×PTGC). This process requires two columns to be connected by a pressure junction, as a replacement for a single narrow bore, short column in ²D. Various ²D₁ and ²D₂ columns may be selected to provide complementary selectivity (polarity) compared to the ¹D column. The tunable residence time arising from differential pressure drop in each ²D column results in a tunable fractional contribution of each column in the ²D separation. A sample mixture comprising different chemical classes, including alkanes and alcohols, is used to identify the feasibility and extent of selectivity tuning possible in GC×PTGC. The column length is also varied due to the imposed challenge of wraparound in the PT coupled column system as pressures are adjusted in the ²D separation. Different experimental parameters, stationary phase materials and column lengths have been applied to investigate and understand the separation behaviour of the ²D PT coupled column GC×GC system. Results are discussed considering analyte retention time, peak width, linear velocity and the contribution of each ²D column. A specific and unexpected example of GC×GC separation was demonstrated where the peak positions of polar and apolar compounds could almost swap their ²D retention position by application of PT. Kerosene was analysed as an example of complex sample analysis by GC×PTGC system. This process is shown to be a practical approach for altering different stationary phase selectivities in a single ²D arrangement in GC×GC.

已在综合二维气相色谱（GC×PTGC）中对第二维（² D）分离实施了压力可调（PT）耦合柱集成。这个过程需要两列将被通过压力连接点处连接，作为用于单个窄孔中的替代品，短柱² D.各种² d ₁和² d ₂相比，可以选择列，以提供互补的选择性（极性）¹ D列。从差动压力下降中的每个所产生的可调谐的停留时间² d柱导致在每列中的可调谐的分数贡献²D分离。使用包含不同化学类别（包括烷烃和醇）的样品混合物来确定在GC×PTGC中可能进行选择性调整的可行性和程度。如压力在调整列长度也因改变，以回绕的在PT耦合塔系统所施加的挑战² d的分离。不同的实验参数，固定相材料和列长度已应用于调查了解的分离行为² d PT耦合柱的GC×GC系统。讨论结果时要考虑到分析物的保留时间，峰宽，线速度和每种²的贡献D列。GC×GC分离的具体的和意想不到的例子证明，其中极性和非极性化合物的峰的位置几乎可以交换它们的²由PT的应用d保持位置。通过GC×PTGC系统分析煤油作为复杂样品分析的实例。该过程被示出为用于在单个改变不同固定相的选择性的实用方法²在GC×GC d布置。