The invention provides an experimental device. An outlet of a displacement pump is in communication with an inlet of a first sampling device. An outlet of the first sampling device is in communicationwith a first inlet of a control valve. A second inlet of the control valve is in communication with an outlet of a return pressure pump. An outlet of the control valve is in communication with a first opening of an adsorption tank, a second opening of the adsorption tank is in communication with a flowmeter, and a third opening of the adsorption tank is in communication with a collection tank. The first sampling device locates in a high temperature chamber. The adsorption tank locates in a low temperature chamber. A valve is arranged between the outlet of the first sampling device and the first inlet of the control valve. A valve is arranged between the third opening of the adsorption tank and the collection tank, and the collection tank is adapted to be heated. The dissolvability of sulfur element in a sulfur-containing gas, calculated based on a gas flow measured by the device provided by the invention and the quantity of elemental sulfur, is more precise.