From
https://www.quora.com/What-is-the-maximum-temperature-a-Bunsen-burner-flame-can-reachAn LPG (propane) flame burns at a maximum of 1980°C.
A natural gas (methane) flame burns at a maximum of 1950 °C.
Both numbers assume that they are being combined with air, which is how most Bunsen burners operate.
If the burner has an oxygen supplied flame the temperature can be much higher. For example, propane with oxygen burns at 2800 °C.