For a shorter period of time [1]

> The lifetime in the air of CO2, the most significant man-made greenhouse gas, is probably the most difficult to determine, because there are several processes that remove carbon dioxide from the atmosphere. Between 65% and 80% of CO2 released into the air dissolves into the ocean over a period of 20–200 years. The rest is removed by slower processes that take up to several hundreds of thousands of years, including chemical weathering and rock formation. This means that once in the atmosphere, carbon dioxide can continue to affect climate for thousands of years.

> Methane, by contrast, is mostly removed from the atmosphere by chemical reaction, persisting for about 12 years. Thus although methane is a potent greenhouse gas, its effect is relatively short-lived.

[1] https://www.theguardian.com/environment/2012/jan/16/greenhou...

You can also pump CO2 into deep coal seams, displacing CH4 which is then burned in a closed capture system. The CO2 released from burning the CH4 is also sequestered resulting in a net gain since CO2 preferentially adsorbs to coal at a roughly 3:1 ratio to CH4. Economically viable coal seams are widespread globally, and exist within 50 km of most coal burning power plants in the United States.

If you bury it deep, millions of years easily.