Processes for converting C8 aromatic hydrocarbons. In some embodiments, a process for converting a hydrocarbon feed that can include C8 aromatic hydrocarbons can include feeding the hydrocarbon feed into a conversion zone and contacting the hydrocarbon feed at least partly in a liquid phase with an isomerization catalyst composition in the conversion zone under conversion conditions to effect isomerization of at least a portion of the C8 aromatic hydrocarbons to produce a conversion product rich in para-xylene. In some embodiments, the isomerization catalyst composition can include a zeolite (preferably a ZSM-5 zeolite) that can have a silica (SiO2) to alumina (AI2O3) molar ratio of 10 to 100, a total surface area of 200 m2/g to 700 m2/g, a micropore surface area of 50 m2/g to 600 m2/g, and an external surface area of 55 m2/g to 550 m2/g.