diff --git a/interfaces/cython/cantera/ck2cti.py b/interfaces/cython/cantera/ck2cti.py
index b19771c7c..9bf7aa9ea 100644
--- a/interfaces/cython/cantera/ck2cti.py
+++ b/interfaces/cython/cantera/ck2cti.py
@@ -40,7 +40,6 @@ import numpy as np
 import re
 import itertools
 import getopt
-import sys
 
 QUANTITY_UNITS = {'MOL': 'mol',
                   'MOLE': 'mol',