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色谱流出峰的拖尾现象普遍存在于制备和大型色谱分离过程中，它直接影响分离的产率和回收率．本文提出采用色谱流出峰形的不对称偏差度来表征色谱流出峰的拖尾程度；并基于液相制备色谱分离过程FAD－SMT模型及吸附速率理论，通过计算机模拟，定量分析了吸附剂性能和操作参数对色谱流出峰形不对称性的影响。结果表明：不仅是吸附剂的热力学和动力学性能（包括吸附相平衡关系、液固两相间的传质阻力）；而且柱的设计和吸附剂的装填状况（包括轴向扩散系数），以及色谱分离的操作条件（进料时间、浓度和流速等）都直接影响色谱流出峰形的不对称性。随着吸附相平衡等温线的非线性程度增大，或者总传质系数的减小，色谱流出峰形的不对称偏差度明显增大；吸附剂吸附容量的减小也将引起色谱流出峰形的不对称偏差度的增加；色谱流出峰形的不对称偏差度与进科体积、浓度和流体线速，以及轴向扩散系数的增大成正比。
Chromatogram peak outflow phenomenon commonly occurs in the preparation and large-scale chromatographic separation process, which directly affects the separation yield and recovery. In this paper, the asymmetry degree of chromatographic outflow peak is used to characterize the tailing of chromatographic outflow peak. Based on FAD-SMT model and adsorption rate theory of liquid chromatographic separation process, the performance of adsorbent and Effect of operating parameters on asymmetry of chromatographic peak effluent. The results show that not only the thermodynamic and kinetic properties of the adsorbent (including the equilibrium of adsorption phase and the mass transfer resistance between liquid and solid phases), but also the design of columns and loading conditions of adsorbents (including axial diffusion coefficient) Separation of the operating conditions (feed time, concentration and flow rate, etc.) have a direct impact on chromatographic peak outflow asymmetry. As the non-linearity of equilibrium phase isotherm increases, or the total mass transfer coefficient decreases, the asymmetry deviation of chromatographic outflow peaks increases obviously. The decrease of adsorbent adsorption capacity will also cause the outflow peak Asymmetry degree of asymmetry increases; asymmetry deviation of chromatographic peak shape is proportional to the volume, concentration and linear velocity of fluid, and the increase of axial diffusion coefficient.