A method for modifying molecular sieves used in methanol-to-gasoline reaction

Abstract

The invention discloses a modification treatment method of a molecular sieve for methanol to gasoline reaction. The method comprises the following steps: mixing and stirring the molecular sieve for methanol to gasoline reaction with an aqueous alkali to obtain a mixture, wherein the aqueous alkali is selected from one or more of Li2CO3, Na2CO3 and K2CO3; transferring the obtained mixture into a high pressure kettle with a polytetrafluoroethylene lining, adding organic amine, sealing, heating and stirring, and then cooling to room temperature, vacuum-filtering, washing to neutral through deionized water, drying at 110 DEG C, passing the night to obtain solid powder; mixing and stirring the obtained solid powder and an acid solution, placing in the high pressure kettle with the polytetrafluoroethylene lining, heating and stirring, and then cooling to room temperature, vacuum-filtering, washing to neutral through the deionized water, drying at 110 DEG C, passing the night, placing in a muffle furnace, calcining at high temperature of 400 DEG C to obtain the modified molecular sieve. Through the adoption of the method disclosed by the invention, the activity, the selectivity and the thermal stability of the molecular sieve are improved.

Description

technical field [0001] The invention belongs to the technical field of methanol-to-gasoline catalysts, in particular to a method for modifying molecular sieves used in methanol-to-gasoline reactions. Background technique [0002] my country is short of oil resources, and the proven oil reserves only account for 1.4% of the world's reserves. However, in recent years, the rapid development of the national economy has increased the demand for energy, and the dependence on oil imports has also increased year by year. my country's energy structure is "rich in coal, low in oil, and short of gas". The reserve, output and consumption of coal resources have reached 12.6%, 35.3% and 34.4% of the world's total. Therefore, vigorously developing the clean transformation and utilization of coal resources has become The current research hotspot and the way out to solve the future energy crisis. [0003] Coal gasification to methanol process is a relatively mature process in the coal chemic...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent CN102513142B "A Preparation Method of Methanol-to-Gasoline Catalyst" adopts acid treatment and hydrothermal treatment to remove the aluminum on the molecular sieve skeleton and increase the silicon-aluminum ratio, which can improve the selectivity of gasoline, but because ZSM-5 itself is a silicon For molecular sieves with higher content and less aluminum content, a large number of aluminum atoms on the skeleton will be removed to destroy the pore structure of the molecular sieve, which will inevitably affect the long-term activity of the molecular sieve

[0005] Chinese patent CN103506150A "Catalyst for methanol to gasoline through water vapor modification and its preparation method and application" mentioned that the use of hydrothermal treatment to remove the amorphous aluminum on the molecular sieve can dredge the pores and The effect of increasing the specific surface area, but the effect is limited compared with the new alkaline treatment