Mesoporous silicon film and two-step preparation method and application thereof

Abstract

The invention provides a mesoporous silicon film and a two-step preparation method and application thereof. The preparation method comprises the following steps: putting cotton into a sulfuric acid solution, stirring and reacting, taking out the cotton after the reaction, diluting with distilled water, standing for layering; carrying out centrifugal separation on the lower layer of a suspension, washing; carrying out dialysis on the centrifuged suspension, adjusting the pH, carrying out ultrasonic treatment to obtain nanocrystalline cellulose; carrying out ultrasonic treatment on the nanocrystalline cellulose, putting the nanocrystalline cellulose into a round-bottom flask, adding glucose, stirring evenly, adding tetraethl silicate, stirring and drying to obtain a mesoporous silicon film A; calcining the mesoporous silicon film A to obtain a mesoporous silicon film B; putting the mesoporous silicon film B into methylbenzene, introducing nitrogen, dropwise adding triethylamine, introducing nitrogen, dropwise adding Diethylphosphatoethyltriethoxysilane, sealing, and shaking to obtain a mesoporous silicon film C; putting the mesoporous silicon film C into concentrated hydrochloric acid and reacting to obtain a mesoporous silicon film D; and washing the mesoporous silicon film D and drying to obtain the final mesoporous silicon film. According to the invention, biomass cellulose is used as a template, has a wide range of sources and is green and environmentally friendly.

Description

technical field [0001] The invention relates to a mesoporous silicon membrane with high selectivity and high adsorption capacity for lanthanum, which adopts a two-step synthesis preparation method and is applied to the adsorption and recovery of rare earth element lanthanum, belonging to the technical field of material preparation and separation. Background technique [0002] Rare earth metals are widely used in electronics, petrochemical, metallurgy, machinery, energy, light industry, environmental protection, agriculture and other fields. Now it has become an extremely important strategic resource. However, after more than half a century of super-intensive mining, China's rare earth resources reserves and guaranteed years have been declining, and the resources in major mining areas have accelerated their decline, and most of the original mine resources have been exhausted. The mining areas are scattered, there are many mines, and the supervision cost is high and difficult...

AI Technical Summary

Problems solved by technology

For example, the solvent extraction technology uses a large amount of organic solvents, which is prone to secondary pollution; the recrystallization method is time-consuming, has a low yield, and has high requirements for the selection of solvents; as a new distillation method, molecular distillation can achieve certain organic matter. Separation, but its equipment structure is complicated, the technical requirements are strict, the investment is huge and the energy is seriously wasted; the membrane separation technology (Membrane Separation Technique, MST), which emerged in the 1860s, is characterized by its high efficiency, energy saving, convenient operation, molecular level filtration, Environmental friendliness and other advantages have been widely used in the production process of enterprises

However, there are still some factors that limit the development of traditional membrane separation technology. For example, the current commercially available membranes (ultrafiltration, microfiltration and reverse osmosis membranes) can only achieve the separation of a certain type of substance and cannot separate a single substance. For organic compounds with similar structures, traditional membranes cannot perform single and efficient selective separation of certain substances

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