CI3 Session Not Expiring On Browser Close

Hi guys,

Using Codeigniter 3.1.2.

Below are my config details for session.

PHP Code:

$config['sess_driver'] = 'database';
$config['sess_cookie_name'] = 'ci_session';
$config['sess_expiration'] = 0;
$config['sess_save_path'] = 'ci_sessions';
$config['sess_match_ip'] = FALSE;
$config['sess_time_to_update'] = 7200;
$config['sess_regenerate_destroy'] = FALSE; 


I am told that upon setting the sess_expiration to 0 that it would be destroyed upon browser close.

However, this does not seem to happen.

Any idea?
Any method I can use to utilise this?

Using javascript seems not practical since it gets triggered when used the back button and when going to a different URL.