Device for generating ultra pure 1-methylcyclopropene

A 1-methylcyclopropene (1-MCP) generating device wherein the flow rate of the carrier gas does not deviate more than 20% from the desired flow rate, comprising:

• a first vessel comprising an inlet, an outlet, and a fluoride ion-containing compound of formula (II)
• wherein Ra, Rb, Rc, Rd are each independently selected from C1-20alkyl, phenyl and naphthyl;
• a second vessel comprising an inlet, an outlet, and a 1-MCP precursor of formula (I)
• wherein X is halogen, or C1-6alkylS(O)2O—;
• R1, R2, R3 are each independently selected from hydrogen, C1-6alkyl, phenyl, C1-6alkyloxy, and halogen;
• a third vessel comprising an inlet, an outlet, and a washing solution;
• a pump to supply a carrier gas that is introduced into the first vessel to transfer the fluoride ion-containing compound of formula (II) to the second vessel where said fluoride ion-containing compound of formula (II) reacts with the 1-MCP precursor of formula (I) and the resulting 1-MCP is transferred with the carrier gas to the third vessel where it bubbles through the washing solution before the carrier gas with the 1-MCP is released to the outside;
• characterized in that the flow rate of the carrier gas is regulated by a mass flow sensor that provides a flow rate signal to a flow control circuit that provides the pump with a modulation signal to regulate the flow rate of the carrier gas and that a flow restrictor is present between the pump and the mass flow sensor.