A regenerated denitration catalyst enhanced liquid and preparation method thereof

Abstract

The present invention belongs to the technical field of flue gas denitration, and specifically relates to a regenerated denitration catalyst strengthening liquid and a preparation method thereof. The technical scheme is a regenerated denitration catalyst strengthening liquid, which is composed of isopropyl trioleyl titanate, tetrabutyl titanate, oxalic acid, water, and methanol. The present invention has the advantage of low surface tension, and can quickly enter the interior of the regenerated catalyst to solidify, thereby improving the mechanical strength of the catalyst and achieving the purpose of increasing the service life of the regenerated denitration catalyst; after solidification inside the catalyst, the present invention makes the catalyst have hydrophobic characteristics, and the water vapor in the flue gas and the water generated by denitration during the use of the catalyst are difficult to condense inside the catalyst, thereby reducing the side reaction rate of SO2 oxidation to generate SO3 and extending the service life of the catalyst; the present invention has excellent compatibility with the denitration catalyst carrier anatase titanium dioxide, which can promote the dispersion of the catalyst active component V2O5, improve the denitration activity, and there is no problem of inhibiting catalytic activity.

Description

Technical Field

[0001] The invention belongs to the technical field of flue gas denitration, and particularly relates to a regenerated denitration catalyst strengthening liquid and a preparation method thereof. Background Art

[0002] After 24,000 hours of operation, the denitration catalyst of flue gas in thermal power units and other non-electric industries (steel, coking and cement industries, etc.) will decay or lose its life. Regenerating the denitration catalyst at the end of its life can achieve the purpose of recycling the waste catalyst, and at the same time, regenerating the catalyst can reduce the cost of the denitration catalyst for the enterprise. Therefore, regenerating the denitration catalyst has excellent economic and social benefits. However, the catalyst at the end of its life has problems such as insufficient mechanical strength and irreversible poisoning of some active components.

[0003] At present, the regeneration process of denitrification catalyst at home and abroad only includes dry / wet cleaning and opening process and active component replenishment process, which cannot regenerate and restore the mechanical strength of the catalyst, and replenishing the active component (V 2 O 5 ) improves SO 2 Oxidation to SO 3 The side reaction rate, SO 3 The rapid generation of not only corrodes the tail flue, but more importantly, the generated SO 3 With the denitrification reactant NH 3 The combination produces ammonium bisulfate, which blocks the catalyst micropores and reduces the service life of the regenerated catalyst. The current service life of the regenerated denitrification catalyst is less than 16,000 hours, and the service life of the catalyst with poor regeneration quality is only 8,000 hours. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a regenerated denitration catalyst strengthening liquid and a preparation method thereof.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A regenerated denitration catalyst strengthening liquid comprises the following components in parts by mass:

[0007] 40-60 parts of isopropyl trioleyl titanate, 10-20 parts of tetrabutyl titanate, 0.5-5 parts of oxalic acid, 3-5 parts of water, 30-50 parts of methanol;

[0008] The method for preparing the above-mentioned regenerated denitration catalyst enhanced liquid comprises the following steps:

[0009] The first step is to weigh tetrabutyl titanate and methanol according to a proportion and mix them to form a mixed solution A, and use oxalic acid to adjust the pH of the mixed solution A to 3-5;

[0010] The second step is to drip the water in the above proportion into the stirred mixed solution A at a dripping speed of 3 ml / min to form a mixed solution B;

[0011] In the third step, after ultrasonic treatment of the mixed solution B formed in the second step for 20 minutes, isopropyl trioleate titanate in the above proportion is added and stirred for 2 hours to obtain the regenerated denitration catalyst enhanced solution.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] First, the reinforcing liquid for the regenerated denitration catalyst of the present invention has the advantage of low surface tension. The reinforcing liquid can quickly enter the interior of the regenerated catalyst and solidify, thereby improving the mechanical strength of the catalyst and achieving the purpose of increasing the service life of the regenerated denitration catalyst. Compared with the new denitration catalyst, the regenerated denitration catalyst treated with the reinforcing liquid can achieve 24,000 hours of in-service operation.

[0014] Second, after the regenerated denitration catalyst strengthening liquid of the present invention is solidified inside the catalyst, the catalyst has a hydrophobic characteristic. During the use of the catalyst, the water vapor in the flue gas and the water generated by denitration are difficult to condense inside the catalyst, thereby reducing SO 2 Oxidation to SO 3 Reduce the side reaction rate and extend the service life of the catalyst;

[0015] Third, the regenerated denitration catalyst strengthening liquid of the present invention is mainly a Ti-based system, which has excellent compatibility with the denitration catalyst carrier anatase titanium dioxide, and can promote the catalyst active component V 2 O 5 The dispersion of the catalyst can improve the denitrification activity without inhibiting the catalytic activity. DETAILED DESCRIPTION

[0016] Embodiment 1:

[0017] 13 parts of tetrabutyl titanate and 20 parts of methanol were weighed and mixed to form a mixed solution A. The pH of the mixed solution A was adjusted to 5 with 2 parts of oxalic acid. 5 parts of water were added dropwise to the stirred mixed solution A at a dropping rate of 3 ml / min to form a mixed solution B. After the mixed solution B was ultrasonically treated for 20 minutes, 60 parts of isopropyl trioleyl titanate were added and stirred for 2 hours to obtain the regenerated denitration catalyst enhanced liquid.

[0018] Embodiment 2:

[0019] Weigh 13 parts of tetrabutyl titanate and 30 parts of methanol to form a mixed solution A, use 2 parts of oxalic acid to adjust the pH of the mixed solution A to 5, add 5 parts of water dropwise to the stirred mixed solution A at a dropping rate of 3 ml / min to form a mixed solution B, ultrasonically treat the mixed solution B for 20 minutes, add 50 parts of isopropyl trioleyl titanate and stir for 2 hours to obtain the regenerated denitration catalyst enhanced liquid.

[0020] Embodiment 3:

[0021] Weigh 13 parts of tetrabutyl titanate and 40 parts of methanol to form a mixed solution A, use 2 parts of oxalic acid to adjust the pH of the mixed solution A to 5, add 5 parts of water dropwise to the stirred mixed solution A at a dropping rate of 3 ml / min to form a mixed solution B, ultrasonically treat the mixed solution B for 20 minutes, add 40 parts of isopropyl trioleyl titanate and stir for 2 hours to obtain the regenerated denitration catalyst enhanced liquid.

[0022] Embodiment 4:

[0023] Weigh 20 parts of tetrabutyl titanate and 33 parts of methanol to form a mixed solution A, use 2 parts of oxalic acid to adjust the pH of the mixed solution A to 5, add 5 parts of water dropwise to the stirred mixed solution A at a dropping rate of 3 ml / min to form a mixed solution B, ultrasonically treat the mixed solution B for 20 min, add 40 parts of isopropyl trioleyl titanate, and stir for 2 h to obtain the regenerated denitration catalyst enhanced liquid.

[0024] Embodiment 5:

[0025] Weigh 20 parts of tetrabutyl titanate and 30 parts of methanol to form a mixed solution A, use 5 parts of oxalic acid to adjust the pH of the mixed solution A to 3, add 5 parts of water dropwise to the stirred mixed solution A at a dropping rate of 3 ml / min to form a mixed solution B, ultrasonically treat the mixed solution B for 20 minutes, add 40 parts of isopropyl trioleyl titanate and stir for 2 hours to obtain the regenerated denitration catalyst enhanced liquid.

[0026] The dried regenerated denitration catalyst is immersed in the strengthening liquid prepared in the present invention for 5 minutes, taken out and dried and roasted to obtain a strengthened regenerated denitration catalyst.

[0027] Refer to the denitrification activity, SO 2 / SO 3 The detection methods of conversion rate and attrition, including denitrification activity and SO 2 / SO 3 The test conditions for conversion rate are: flue gas temperature 360℃, catalyst test space velocity 5000h -, catalyst test area velocity 23m / h, test inlet NOx concentration 500mg / Nm 3 , test inlet SO2 concentration 6500mg / Nm 3 .

[0028] The performance indicators of the regenerated denitration catalyst prepared and treated in the above examples and the regenerated denitration catalyst not treated with the enhanced solution of the present invention are as follows:

[0029] project Original regenerated denitrification catalyst Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5 Denitrification activity (m / h) 35.7 36.6 37.2 38.7 39.6 40.7 <![CDATA[SO 2 / SO 3 Conversion rate (%)]]> 0.57 0.21 0.29 0.33 0.39 0.41 Wear (mg / 100U) 149.7 89.46 113.7 120.6 119.9 107.2

Claims

1. A method for preparing a regenerated denitration catalyst strengthening liquid, characterized in that: The raw material components include by mass: 40-60 parts of isopropyl trioleyl titanate, 10-20 parts of tetrabutyl titanate, 0.5-5 parts of oxalic acid, 3-5 parts of water, 30-50 parts of methanol; The method for preparing the regenerated denitration catalyst enhanced liquid comprises the following steps: The first step is to weigh tetrabutyl titanate and methanol according to a proportion and mix them to form a mixed solution A, and use oxalic acid to adjust the pH of the mixed solution A to 3-5; The second step is to drip the water in the above proportion into the stirred mixed solution A at a dripping speed of 3 ml / min to form a mixed solution B; In the third step, after ultrasonic treatment of the mixed solution B formed in the second step for 20 minutes, isopropyl trioleate titanate in the above proportion is added and stirred for 2 hours to obtain the regenerated denitration catalyst enhanced solution.