How to make a javascript object from a string? [closed]

I have a string value e.g.:

var keyword_custType = '[Private customer|PRIVATE, Corporate customer|COMPANY, Sole trader|SOLETRADER, Corporate Group|CORPGROUP]';

I would like to create a javascript object from it (array). I tried:

var obj = JSON.parse(keyword_custType);

But then I get an error: Uncaught SyntaxError: Unexpected token P in JSON at position 1 at JSON.parse ().

What should I do to create a js array from the string?