The present disclosure relates a system of preparing a phthalonitrile-based compound using a continuous process, the preparation system including: a first reaction unit filled with a mixture including a phthalic acid-based compound and a nitrile-based compound; a second reaction unit connected to the first reaction unit; and a discharge unit connected to the second reaction unit, and in the second reaction unit, there is a fluid flow from the first reaction unit direction to the discharge unit direction, wherein the length of the second reaction unit in the fluid flow direction is 10 fold or more the mean square root of the cross-sectional area perpendicular to the fluid flow direction; and a method of preparing a phthalonitrile-based compound using the same.

The present disclosure relates a system of preparing a phthalonitrile-based compound using a continuous process, the preparation system including: a first reaction unit filled with a mixture including a phthalic acid-based compound and a nitrile-based compound; a second reaction unit connected to the first reaction unit; and a discharge unit connected to the second reaction unit, and in the second reaction unit, there is a fluid flow from the first reaction unit direction to the discharge unit direction, wherein the length of the second reaction unit in the fluid flow direction is 10 fold or more the mean square root of the cross-sectional area perpendicular to the fluid flow direction; and a method of preparing a phthalonitrile-based compound using the same.