Magnesium oxide/magnesium hydroxide loading body with high specific surface area and preparation method thereof

The invention relates to a method for preparing a magnesium oxide/magnesium hydroxide carrier with a high specific surface area, which comprises the following steps: step 1, preparing an adsorbent substrate material: cleaning and drying straw agricultural wastes, cooling, and measuring the ash content gt of the straw agricultural wastes; when the content is 10%, NaOH is used for preliminarily removing ash; the method comprises the following steps of: crushing by using a crusher, preliminarily screening, storing sieved corn cob residue powder for later use, putting the sieved corn cob residue powder into a high-temperature pyrolysis device with airtight protection, introducing inert gas, and heating to 350-600 DEG C for carbonization. The biomass material which is low in price, easy to obtain and renewable is used as a preparation raw material, the biomass material has the advantages of being rich in reserves, low in cost and environmentally friendly, and high-value utilization of the biomass material and wast