Ubuntu :: Use A Script To "scramble" A Text File's Content Using A "algorithm" File With Sed?

I want to use a script to "scramble" a text file's content using a "algorithm" file with sed. But I can t figure out how to swap characters instead of words within the file. I want to do this for example:

Code:

Algorithm:

a > b
c > e
t > z

Input:

Cat C A T Cats

Output:

ebz e b z ebzs

I can swap out entire words, but this is not practical for my usage. How can the SED syntax be formatted to do this? The commands will be in a text file called by sed with the -f flag.