You’ve done the right thing to power it off immediately and removing the SIM card. Rather than using rice, I’d suggest using a synthetic desiccant like silica gel, as this will absorb more moisture, plus you don’t up with gooey rice around your phone. You may already have some silic gel as they often come with packaging and some cat litters are actually silica gel. If you don’t have any, it is pretty cheap to buy online. Put the iphone in box or bag you can make airtight (you don’t want to be absorbing moisture from the room, just the iPhone), cover in silica gel, seal the box/bag and leave for at least 2 days.