Can I switch my account type e.g. from Personal to Business or Academic etc.?
It is not possible to edit your profile and switch your account type.
For example, if you have a Personal account and want a Business account, you would have to create a separate account. You would have to go to www.quandl.com, click "Sign Up" at the top right corner, choose "Business" as your purpose, and use a different email address from the one in your Personal account.
It is free to create new accounts and you are allowed to have multiple accounts for different purposes.