The generator matrix

 1  0  1  1  1  0  1  1  0  1  1  0  1  1  1  1  1  1  0  X  1  1  0  X
 0  1  1  0  1  1  0 X+1  1  1  0  1 X+1 X+1 X+1  1  0  X  1  1  0  X  1  1
 0  0  X  0  0  0  0  0  0  X  X  X  0  0  X  X  0  X  0  X  X  X  X  X
 0  0  0  X  0  0  0  X  0  X  X  0  0  X  X  0  X  0  X  X  X  0  0  0
 0  0  0  0  X  0  0  0  X  X  0  X  X  X  0  0  X  X  0  0  X  X  X  X
 0  0  0  0  0  X  0  X  X  X  0  0  0  X  0  X  X  X  0  X  0  0  0  X
 0  0  0  0  0  0  X  X  0  X  0  X  X  X  X  X  0  X  X  0  0  0  0  0

generates a code of length 24 over Z2[X]/(X^2) who´s minimum homogenous weight is 20.

Homogenous weight enumerator: w(x)=1x^0+144x^20+236x^24+120x^28+3x^32+8x^36

The gray image is a linear code over GF(2) with n=48, k=9 and d=20.
As d=20 is an upper bound for linear (48,9,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 9.
This code was found by Heurico 1.16 in 0.0198 seconds.