Asking about supply voltage of AD8672
The permissible total supply voltage is given in the absolute maximum ratings at 36V. As always, you should not go right up to the absolute maximum, and 30V nominal might be a reasonable limit since it is specified at +/-15V.
There is no ground pin on this chip, like most op-amps, so the chip has no real way of knowing how the supply is split up, if at all.
However, the input common mode range is only within 2.5 or 3V of each supply, so it may not work properly in circuits designed for “single-supply” op-amps with input common mode range that extends to the negative supply rail.
The output does not swing all that close to either supply rail, so you need to take that into account as well. Single supply op-amps usually swing very close to the negative rail, particularly with a load from the output to the negative rail only (sourcing current only).