I don't have a 2i2 or iPad but it looks like you should be able to do it, though you may need an adaptor cable and a powered hub. I found these instructions on the Focusrite website:
https://support.focusrite.com/hc/en-gb/articles/115005430409-Can-I-use-my-bus-powered-Scarlett-with-an-iPad-Lightning-port-
There's video on that page showing how to connect a bus-powered Scarlett to an iPad via a powered hub, which I think would apply to the 2i2.
Note: On that same page it says "If you have a Scarlett 3rd Gen interface, please make sure you update the firmware on your Scarlett first, before connecting it to an iPad". The link takes you to:
https://support.focusrite.com/hc/en-gb/articles/360021869499-Updating-the-Firmware-of-Focusrite-Interface-using-Focusrite-Control
Here are some other related support pages..
https://support.focusrite.com/hc/en-gb/articles/206849159-How-do-I-connect-my-mains-powered-Scarlett-Clarett-or-Clarett-USB-interface-to-an-iPad-Lightning-port-
https://support.focusrite.com/hc/en-gb/articles/360001504965-Focusrite-iOS-12-compatibility-information
https://support.focusrite.com/hc/en-gb/articles/212028389-Focusrite-iOS-Control-Basic-setup
https://focusrite.com/en/news/focusrite-sound-now-ipad-pro
