Method for adsorbing ethylene gas using amorphous granular starch

A method for adsorbing ethylene gas using amorphous granular starch, comprising the following steps:

• (1) preparation of an amorphous granular starch comprising:
• (a) pulping with an ethanol aqueous solution to obtain a starch slurry with a dry basis mass fraction of 10% to 15%;
• (b) keeping the starch slurry obtained in step (a) in a water bath with constant temperature of 25-40° C., adding a NaOH solution dropwise, and stirring to react for 20-60 min;
• (c) centrifuging the starch slurry obtained in step (b) to obtain a first solid and a first liquid, washing the first solid with ethanol solution, neutralizing the first solid with an ethanol hydrochloride solution, centrifuging to obtain a second solid and a second liquid, and washing the second solid with ethanol solution to obtain a treated starch;
• and
• (d) drying and sieving the treated starch obtained in step (c) to obtain the amorphous granular starch;
• and
• (2) adsorption of ethylene by the amorphous granular starch comprising:
• (a) placing the amorphous granular starch in a high-pressure reactor, wherein the amount of the amorphous granular starch is 20%-30% of the reactor's volume;
• (b) vacuumizing the reactor and then flushing the reactor with the ethylene gas under the condition of 0.8-1.5 Mpa and 20-30° C. to react for 15-25 h;
• and
• (c) after a reaction between the amorphous granular starch and the ethylene gas is completed, opening a gas outlet valve and removing unadsorbed ethylene to obtain a starch powder product which has adsorbed the ethylene.