Porous adsorption material for removing neon from helium and preparation method thereof

A preparation method of a porous adsorption material for removing neon from helium, comprising:

• (1) crushing a lignin raw material to obtain powder;
• mixing 20-30 parts of the powder with 40-50 parts of deionized water in parts by weight to obtain a fermentation material, adding mixed microorganisms to the fermentation material for aerobic fermentation, followed by filtering, drying, crushing, and sieving to obtain a fermented lignin raw material;
• wherein the mixed microorganisms comprise Bacillus licheniformis, Bacillus subtilis, and Rhizopus oryzae;
• and the lignin raw material comprises coconut shells, olive shells, and bamboo in a weight ratio of 1:(1.3-1.5):(0.5-0.7);
• (2) mixing 1 part by weight of the fermented lignin raw material with 10-12 parts by weight of hydrochloric acid (HCl) solution to obtain a first mixture, ultrasonically dispersing the first mixture for 40-50 minutes to obtain a dispersed mixture, stirring the dispersed mixture at 80-85 Celsius degrees (° C.) for 25-30 hours (h) to obtain a first stirred mixture, washing the first stirred mixture with deionized water until the first stirred mixture is neutral to obtain a neutral mixture, and performing vacuum drying on the neutral mixture to obtain a carbon precursor;
• (3) stirring and impregnating the carbon precursor in a mixed solution containing a metal salt and a surfactant to obtain a metal salt-impregnated carbon precursor;
• wherein the metal salt is one or more selected from the group consisting of a sodium salt, a potassium salt, a magnesium salt, and a zinc salt;
• the surfactant comprises sodium dodecylbenzenesulfonate, octadeyl dimethyl betaine, and a zwitterionic surfactant in a weight ratio of 1:(1.2-1.4):(0.3-0.5);
• conditions for the stirring and the impregnating comprise an impregnation time of 20-24 h, a temperature of 60-80° C., and a stirring speed of 200-300 revolutions per minute (rpm);
• and an impregnation solid-to-liquid ratio of the carbon precursor to the mixed solution is in a range from 1:15 to 1:20 gram per milliliter (g/mL);
• wherein a preparation method of the zwitterionic surfactant comprises the following steps:
• S1, heating a HCl aqueous solution to 40-45° C. to obtain a heated HCl aqueous solution, adding N,N-dimethylhexadecylamine dropwise to the heated HCl aqueous solution, maintaining a temperature of the heated HCl aqueous solution added with the N,N-dimethylhexadecylamine for reaction for 1-1.5 h to obtain a first reacted solution, adding an ethanol solution of epoxidized soybean oil dropwise to the first reacted solution, controlling a temperature of the first reacted solution added with the ethanol solution of epoxidized soybean oil at 50-55° C. to react for 6-8 h to obtain a second reacted solution, and removing ethanol and water from the second reacted solution by distillation under reduced pressure to obtain an intermediate 1;
• wherein a molar ratio of the N,N-dimethylhexadecylamine:HCl:
• the epoxidized soybean oil is 3:3:(0.8-1);
• and S2, dissolving 10 parts by weight of the intermediate 1 in an ethanol aqueous solution, and adding 0.5-0.7 parts by weight of sodium hydroxide (NaOH) in the ethanol aqueous solution to obtain a second mixture;
• stirring the second mixture under reflux for reaction for 4-6 h to obtain a second stirred mixture, stopping the reaction, filtering the second stirred mixture to obtain a filter residue, washing the filter residue with absolute ethanol to obtain a washed filter residue, and drying the washed filter residue under vacuum to obtain the zwitterionic surfactant;
• (4) washing the metal salt-impregnated carbon precursor to remove a metal salt deposited in excess, followed by drying to obtain a washed carbon precursor;
• and
• (5) activating the washed carbon precursor with carbon dioxide to effect pore formation, thereby obtaining the porous adsorption material for removing neon from helium;
• wherein the activating the washed carbon precursor with carbon dioxide to effect pore formation comprises heating the washed carbon precursor to obtain a heated carbon precursor, and activating the heated carbon precursor with the carbon dioxide to effect pore formation, wherein a heating rate is in a range of 5-10 Celsius degrees per minute (C/min), an activation temperature is in a range of 800-1000° C., an activation duration is in a range of 80-100 minutes, and a concentration of the carbon dioxide is in a range of 80-100%.