Large-airspeed high-activity heavy naphtha desulfurizer and preparation method thereof

Abstract

The invention discloses a high-airspeed high-activity heavy naphtha desulfurizing agent and a preparation method thereof. The high-airspeed high-activity heavy naphtha desulfurizing agent consists of the following components: 30-50% of activated aluminum oxide, 5-20% of a molecular sieve, 20-40% of a first active metal element, 10-30% of a second active metal element and 1-5% of an auxiliary agent, the method comprises the following steps: 1, uniformly mixing an oxide containing active metal elements with a carrier raw material to obtain dry powder; 2, preparing the dried powder into pellets to obtain a desulfurizer A; 3, carrying out equivalent-volume impregnation on the desulfurizer A by using a mixed salt solution containing active metal elements to obtain a desulfurizer B; 4, activating; and 5, carrying out surface oxidation treatment. The carrier, the active substance and the auxiliary agent are designed, so that the adsorption capacity and the sulfur capacity of the desulfurizing agent are improved; by controlling the adding form of the active components step by step and combining activation and surface oxidation treatment, the activation degree is enhanced, the treatment capacity and desulfurization precision of the desulfurizing agent are improved, and the requirements of storage, transportation and production of the desulfurizing agent are met.

Description

technical field [0001] The invention belongs to the field of petrochemical catalytic purification agents, in particular to a high space velocity and high activity heavy naphtha desulfurizer and a preparation method thereof. Background technique [0002] Naphtha is the product of primary or secondary processing of crude oil or other oil products by refining and chemical enterprises. Due to the high latent content of aromatics and low nitrogen and sulfur content in naphtha, it is the product of catalytic reforming or isomerization to produce high octane. It is the most important raw material for gasoline, aromatics and hydrogen. Especially in recent years, the domestic demand for clean gasoline, benzene, toluene, xylene and other chemical raw materials has been strong, which has promoted the larger and larger scale of naphtha processing units. Therefore, the demand for naphtha raw materials has continued to increase. Conflicts are becoming increasingly prominent. In order to...

AI Technical Summary

Problems solved by technology

However, in the preparation process of the desulfurizer, the activated carbon needs to be washed with a large amount of water after being modified with a strong acid, resulting in waste of water resources and environmental pollution.

Activated carbon desulfurization is mainly based on physical adsorption, and the optimum operating temperature should not exceed 50°C. At the same time, oxygen is beneficial to activated carbon desulfurization. Therefore, when using activated carbon desulfurizer, it is required to contain a certain amount of oxygen in the raw material, which limits its scope of use.

When the activated carbon desulfurizer of this patent is used for desulfurization of gasoline and diesel oil, it can reduce the content of 150μg·g -1 The total sulfur removal to 10μg·g -1 Below, the desulfurization accuracy is low, the sulfur capacity is low, and it is not suitable for use at a temperature above 130°C

[0008] At present, most of the solid desulfurizers used in industry use metal oxides as active components. Although metal oxides have a good removal effect on hydrogen sulfide, they have poor removal ability on organic sulfur such as mercaptans and sulfides. Applying it to the heavy naphtha desulfurization process will often cause the total sulfur content in the purified heavy naphtha to exceed the standard, causing subsequent catalyst poisoning and product quality decline, affecting the normal production

[0009] In addition, with the continuous expansion of the demand for heavy naphtha, the annual desulfurization and purification treatment capacity of heavy naphtha is also increasing, and the device is in high-load production. However, when the device processing capacity (liquid space velocity) increases, the oil on the surface of desulfurizer The shorter the residence time, the sulfides cannot quickly react and adsorb with the active substances, which will also cause the sulfur content of the purified heavy naphtha to exceed the standard, which limits the production capacity of the enterprise

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