Is it possible to power an AC light bulb with DC voltage, if not then why?
Figure 1. A typical arrangement for a cheap capacitive dropper power-supply LED bulb. Image source: Dimmers for LEDs.
You have two likely problems:

The lamp will contain multiple series-connect LEDs which each have a forward voltage of several volts. Your batteries haven't enough voltage to get them to turn on.
Many of these lamps use a capacitor (C1 in Figure 1) to drop the AC voltage without generating a load of heat. (R1 is a very high-value resistor just to discharge the capacitor when the power is turned off.) As the capacitor symbol suggests, it is a pair of plates with a gap between them so, while it conducts AC to an extent which increases with frequency, it blocks DC completely.


The bulb consumed ~60 mV (voltage dropped to ~1.80V) in several seconds and did nothing.

No, the battery lost that voltage due to it's internal resistance. There was only 1.8 V left to be applied across your lamp. That suggests that either something in the lamp is drawing some significant current or that the lamp is drawing a small current but that your batteries are flat. Without knowing the innards of that lamp it is not possible to be more specific.