Disable standard email notifications for the Approval Process

As an admin, you can't disable the standard approval request email from being sent.

You can update the user's record to prevent the user from getting the emails by setting the 'Receive Approval Request Emails' field to 'Never'.  With the field set to 'Never', you would create a workflow rule to generate emails.

Classic:
1. Go to Setup | Manage Users | Users

2. Select any user, then click Edit button

3. Under 'Receive Approval Request Emails' field, select "Never"

4. Save


Lightning
1. Click the Gear icon then go to Setup | Administration | Users

2. Select any user, then click Edit button

3. Under 'Receive Approval Request Emails' field, select "Never"

4. Save