Preparation method of directional zeolite membrane

Abstract

The invention discloses a preparation method of a directional zeolite membrane. The preparation method of the directional zeolite membrane comprises the following steps: a metal substrate is provided; a zeolite crystal is provided, and the aspect ratio of the zeolite crystal is at least 2; the zeolite crystal is flatly laid on the metal substrate to obtain a first metal substrate; precursor liquid is attached on the surface of the first metal substrate to obtain a second metal substrate, and contains a first structure guide agent and a solvent; and the second metal substrate and a preset quantity of solvent are put in a closed container to be continuously heated at 100-550 DEG C for reaction by at least 15 minutes to generate the directional zeolite membrane. The directional zeolite membrane is uniform in thickness, and is allowed to completely coat the surface of the substrate to form a compact film, so that the effect of corrosion resistance of the directional zeolite membrane is improved.

Description

technical field [0001] The present invention relates to a preparation method of a zeolite membrane, in particular to a preparation method of a directional zeolite membrane. Background technique [0002] In order to protect metal products from corrosion, the conventional method is to treat the metal surface with phosphate and chromate to increase the durability of metal products. However, at present, many countries have enacted RoHS (Restriction of the use of certain hazardous substance in electronics equipment) by legislation to restrict the use of hexavalent chromium, lead and mercury and other chemicals in electrical appliances and household products. Coating on the metal surface to slow down its corrosion rate has become an emerging metal surface treatment technology. [0003] The preparation method of the existing zeolite membrane is a wet hydrothermal membrane preparation method, which is to add a tetrapropylammonium hydroxide aqueous solution to tetraethoxysilane, and...

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Problems solved by technology

[0004] Although the existing zeolite membrane can block external water vapor and oxygen to achieve the effect of protecting the metal substrate and slowing down the rust rate, however, in the existing zeolite membrane obtained by the preparation method of the existing zeolite membrane, Due to the random stacking of zeolite crystals, the effect of blocking external water vapor and oxygen is not good. If the existing anti-zeolite film with good anti-corrosion effect is to be synthesized, the thickness must also be increased, and it is impossible to prepare a film with good anti-corrosion effect. ; In addition, in the preparation method of this existing zeolite membrane, need to use a large amount of this precursor solution to make this metal substrate submerge in this precursor solution, allow reaction to carry out evenly on each surface of this metal substrate, but The alkaline precursor solution in the reaction process will cause corrosion of the metal substrate, resulting in a decrease in the mechanical strength of the metal substrate. Moreover, the solution before the reaction still contains raw materials such as tetrapropylammonium hydroxide and tetraethoxysilane. , but due to the difficulty of separation, it can only be reduced to useless waste liquid. Invisibly, the amount of waste liquid accumulated in the process of preparing the existing zeolite membrane is obviously contrary to the trend of environmental protection.

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