Haloalkane activated molecular sieve with low boiling point and refining process thereof

Abstract

The invention discloses a process for activating A-type or X-type molecular sieve under room temperature by using chloromethane (chloroethane). The activated molecular sieve is used for refining haloalkane with low boiling point such as chloromethane (chloroethane) and methyl bromide, and the refining process comprises the following steps: an exothermic reaction between the crystals in the molecular sieve and the chloromethane (chloroethane) is processed with a chemical equation of H2O+RCL->ROH+HCL+Q, in which the generated alcohol and hydrogen chloride are absorbed by alkali liquor and the unreacted chloromethane (chloroethane) are recycled after being condensed. After being fully purged by high-purity nitrogen, the activated molecular sieve is placed into a molecular sieve tower of the haloalkane refining system and then the haloalkane with low boiling point is refined according to the processes of adding the haloalkane liquid-phase absorbent, gasifying, alkali washing and acid removing, cooling and impurity removing, drying and dewatering, removing the molecular sieve and fully condensing and liquefying so as to refine the finished products with high purity.

Description

technical field [0001] The invention relates to a low-boiling point haloalk activated molecular sieve and a low-boiling point haloalk purification process. Background technique [0002] Commercially available molecular sieves of 3A, 4A, 5A, 10X, 13X and other types commonly used in industry and laboratories must be activated before they can be used. The activation method of molecular sieves is usually: after washing with water (accompanied by heat release), dry in an oven, heat in a muffle furnace at 150°C for 1-1.5 hours, heat up to 350°C for 3-5 hours, and finally heat up to 550°C for 3 hours . After stopping heating, cool to room temperature in a desiccator for later use. The above method can only be used to activate a small amount of molecular sieves in the laboratory, and large-scale special facilities will be required to use activated molecular sieves in large quantities in industry. It can be seen that the activation of molecular sieves has certain requirements for...

AI Technical Summary

Problems solved by technology

It can be seen that the activation of molecular sieves has certain requirements for equipment, and the requirements for temperature control are also quite strict. If the temperature is low, the activation effect will not be good, which will affect the adsorption capacity. If the temperature is high, the crystal structure of the molecular sieve will be destroyed, and the adsorption capacity will be reduced or lost.

Molecular sieves in the form of solid particles have difficulty in heat transfer. When a large amount of heating is activated, it is inevitable that the temperature of the inner and outer layers will be inconsistent, which will lead to uneven activation states and make the molecular sieve unable to achieve the expected use effect.

The biggest disadvantage of this traditional molecular sieve heating and activation method is that the power consumption and energy consumption are very high, which has always been the biggest problem for activating molecular sieves. On the basis of a large number of experiments, the present invention proposes a chemical activation method for molecular sieves at room temperature , the activation of molecular sieves with methyl chloride (b) can solve the problem of inhomogeneous activation of molecular sieves

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