Activation method of nickel-aluminum alloy catalyst and application thereof

Abstract

The application provides a kind of activation method of nickel-aluminum alloy catalyst and its application, using lye to activate nickel-aluminum alloy catalyst filled in fixed bed reactor;Temperature inductor and flowmeter are arranged at the lye inlet of fixed bed reactor;Several temperature inductors are arranged on the catalyst bed in fixed bed reactor;In activation, total amount of dissolved aluminum M of nickel-aluminum alloy catalyst meets activation time t and temperature rise △T in fixed bed reactor, temperature rise △T meets lye flow F1 at lye inlet, when total amount of dissolved aluminum M is 0wt% < M ≤ 12wt%, then, if 8 ℃ ≤ △T ≤ 10 ℃, flow F1 is 2-4 t / h;If △T < 8 ℃ or △T > 10 ℃, increase / decrease lye flow at the rate of v1, so that 8 ℃ ≤ △T ≤ 10 ℃.The application also provides that the above method is used for preparing 1,4-butanediol by catalytic hydrogenation of 1,4-butynediol, and the method of the application realizes automatic activation of activation process and precise control of activation endpoint.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst activation, specifically to an activation method for precisely controlling the rate and total amount of aluminum dissolution during the activation process of a nickel-aluminum alloy catalyst. Background Technology

[0002] Nickel-aluminum alloy catalysts do not exhibit activity before activation because the nickel is encapsulated by aluminum. The activation process involves reacting aluminum with an alkaline solution to remove the surface aluminum, forming a framework and exposing the nickel, thus revealing its activity. Different nickel-aluminum alloy catalysts have specific requirements for the rate and total amount of aluminum dissolution to meet activity demands. Taking the hydrogenation of 1,4-butynediol to 1,4-butanediol as an example, the aluminum dissolution rate must be controlled between 3 and 3.5 wt% / h. If the dissolution rate is below 3 wt% / h, the amount of alkaline solution is manually increased; if the rate is above 3.5 wt% / h, the amount of alkaline solution is manually decreased. This process involves numerous steps, exhibits lag, and makes it difficult to accurately control the target endpoint, thus negatively impacting catalyst activity.

[0003] To achieve the catalyst activation target, personnel need to continuously sample and analyze the changes in inlet and outlet NaOH concentrations to calculate the aluminum dissolution rate and total amount dissolved. Since aluminum and alkali solution produce hydrogen gas, this operation carries certain operational risks. Summary of the Invention

[0004] In view of the problems in the prior art, the present invention provides an activation method for nickel-aluminum alloy catalysts. The temperature rise ΔT during the activation process is calculated by the reactor temperature and the amount of activation tail gas released. The aluminum dissolution rate at this time is calculated based on ΔT. The rate and total amount of aluminum dissolution are monitored in real time, ensuring accurate control of the activation target. No sampling and analysis by personnel is required, which essentially reduces the operational risk.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The present invention provides a method for activating a nickel-aluminum alloy catalyst in a first aspect, wherein an alkaline solution is used to activate the nickel-aluminum alloy catalyst packed in a fixed-bed reactor; a temperature sensor and a flow meter are installed at the inlet of the alkaline solution in the fixed-bed reactor to measure the inlet temperature T7 of the alkaline solution and control the alkaline solution to enter the fixed-bed reactor at a flow rate F1; a plurality of temperature sensors are installed on the catalyst bed in the fixed-bed reactor to measure the temperature T at various points.

[0007] During the activation process, the total dissolved aluminum M of the nickel-aluminum alloy catalyst satisfies the following relationship with the activation time t and the temperature rise ΔT in the fixed-bed reactor:

[0008]

[0009] Wherein, the temperature rise ΔT = T in the fixed-bed reactor max -T7,T max This is the highest temperature among the catalyst beds in the fixed-bed reactor.

[0010] The temperature rise ΔT in the fixed-bed reactor and the alkaline flow rate F1 at the alkaline inlet satisfy the following relationship:

[0011] When the total dissolved aluminum M is between 0 wt% and 12 wt%, then

[0012] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 2~4t / h;

[0013] If ΔT < 8℃, increase the alkali flow rate at a rate of v1 so that 8℃ ≤ ΔT ≤ 10℃;

[0014] If ΔT > 10℃, decrease the alkali flow rate at a rate of v1 to make 8℃ ≤ ΔT ≤ 10℃;

[0015] When the total dissolved aluminum M is between 12wt% and 21wt%, then

[0016] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 4~8t / h;

[0017] If ΔT < 8℃, increase the alkali flow rate at a rate of v2 to make 8℃ ≤ ΔT ≤ 10℃;

[0018] If ΔT > 10℃, decrease the alkali flow rate at a rate of v2 to make 8℃ ≤ ΔT ≤ 10℃;

[0019] When the total dissolved aluminum M is between 21 wt% and 26 wt%, then

[0020] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0021] If ΔT < 8℃, increase the alkali flow rate at a rate of v3 so that 8℃ ≤ ΔT ≤ 10℃;

[0022] If ΔT > 10℃, decrease the alkali flow rate at a rate of v3 to make 8℃ ≤ ΔT ≤ 10℃;

[0023] When the total dissolved aluminum M > 26 wt%, stop the alkaline solution from entering the fixed-bed reactor; where v1 < v2 < v3.

[0024] In some specific embodiments, an activation tail gas flow meter is installed in the fixed-bed reactor to measure the activation tail gas flow rate F2 of the nickel-aluminum alloy catalyst during the activation process; based on the activation tail gas flow rate F2, the temperature rise ΔT in the fixed-bed reactor is corrected to [0.05×F2 / (T)]. max-T7)]+(T max -T7).

[0025] In some specific embodiments, the nickel content in the nickel-aluminum alloy catalyst involved in the present invention is 40-70 wt%; for example, the nickel-aluminum ratio in the nickel-aluminum alloy catalyst is 58:42.

[0026] In some specific embodiments, the alkaline solution is selected from lithium hydroxide aqueous solution, sodium hydroxide aqueous solution or potassium hydroxide aqueous solution; specifically, the concentration of the alkaline solution is 5 to 50 wt%, for example, 10 wt%, 15 wt%, 40 wt%, 45 wt%, preferably 20 to 35 wt%, for example, 25 wt%, 30 wt%.

[0027] In some specific implementations, v1 is taken from 0.2 to 0.5 t / h, v2 is taken from 0.5 to 1 t / h, and v3 is taken from 1 to 4 t / h.

[0028] In some specific embodiments, before activating the catalyst, the nickel-aluminum alloy catalyst in the fixed-bed reactor is washed with water for 2 to 4 hours to remove impurities from the surface of the nickel-aluminum alloy catalyst.

[0029] In some specific implementations, once the total amount of dissolved aluminum reaches the required level, the flow of alkaline solution is stopped and the catalyst is washed with deionized water for 4–8 hours.

[0030] In a second aspect, the present invention also provides a method for the catalytic hydrogenation of 1,4-butynediol to prepare 1,4-butanediol, wherein the hydrogenation catalyst is activated by the above-mentioned activation method before the hydrogenation reaction.

[0031] In some specific embodiments, the conversion of 1,4-butynediol is greater than 99.8%, and the selectivity of 1,4-butanediol is greater than 99.2%.

[0032] The above technical solution achieves the following technical effects:

[0033] The activation method provided by this invention calculates the temperature rise ΔT during the activation process through a temperature rise module, and then establishes a series control relationship between ΔT and the alkaline solution flow rate F1, thereby achieving precise control of the aluminum dissolution rate and activation endpoint during the activation process. Detailed Implementation

[0034] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0035] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0036] This invention provides a method for activating a nickel-aluminum alloy catalyst, which uses an alkaline solution to activate the nickel-aluminum alloy catalyst packed in a fixed-bed reactor. A temperature sensor and a flow meter are installed at the inlet of the alkaline solution in the fixed-bed reactor to measure the inlet temperature T7 of the alkaline solution and control the flow rate F1 of the alkaline solution into the fixed-bed reactor. Several temperature sensors are installed on the catalyst bed in the fixed-bed reactor to measure the temperature T at various points.

[0037] During the activation process, the total dissolved aluminum M of the nickel-aluminum alloy catalyst satisfies the following relationship with the activation time t and the temperature rise ΔT in the fixed-bed reactor:

[0038]

[0039] Wherein, the temperature rise ΔT = T in the fixed-bed reactor max -T7,T max This is the highest temperature among the catalyst beds in the fixed-bed reactor.

[0040] The aluminum dissolution rate v and the reactor temperature rise ΔT satisfy the following relationship: v = 0.25 × ΔT + 1; the activation rate v can be controlled by the reactor temperature rise ΔT to meet the aluminum dissolution rate requirements before catalyst use; for example, if the activation rate is required to be controlled at 3-3.5 wt% / h during catalyst activation, this can be achieved by controlling the reactor temperature rise ΔT at 8-10℃.

[0041] Taking the 1,4-butynediol hydrogenation catalyst as an example, the aluminum dissolution rate during activation is controlled at 3-3.5 wt% / h. The temperature rise ΔT in the fixed-bed reactor and the alkaline flow rate F1 at the alkaline inlet satisfy the following relationship:

[0042] When the total dissolved aluminum M is between 0 wt% and 12 wt% (i.e., in the initial stage of catalyst activation), then

[0043] If 8℃≤△T≤10℃, control the flow rate F1 of the alkali solution to 2~4t / h, for example, 2.5t / h, 3t / h;

[0044] If ΔT < 8℃, increase the alkali flow rate at a rate of v1 so that 8℃ ≤ ΔT ≤ 10℃;

[0045] If ΔT > 10℃, decrease the alkali flow rate at a rate of v1 to make 8℃ ≤ ΔT ≤ 10℃;

[0046] When the total dissolved aluminum M is between 12wt% and 21wt% (i.e., the mid-stage of catalyst activation), then

[0047] If 8℃≤△T≤10℃, control the flow rate F1 of the alkali solution to 4~8t / h, for example, 5t / h, 6t / h, 7t / h;

[0048] If ΔT < 8℃, increase the alkali flow rate at a rate of v2 to make 8℃ ≤ ΔT ≤ 10℃;

[0049] If ΔT > 10℃, decrease the alkali flow rate at a rate of v2 to make 8℃ ≤ ΔT ≤ 10℃;

[0050] When the total dissolved aluminum M is between 21 wt% and 26 wt% (i.e., the later stage of catalyst activation), then

[0051] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0052] If ΔT < 8℃, increase the alkali flow rate at a rate of v3 so that 8℃ ≤ ΔT ≤ 10℃; if ΔT > 10℃, decrease the alkali flow rate at a rate of v3 so that 8℃ ≤ ΔT ≤ 10℃.

[0053] When the total dissolved aluminum M > 26 wt%, stop the alkaline solution from entering the fixed-bed reactor; where v1 < v2 < v3.

[0054] In some specific implementations, v1 is taken from 0.2 to 0.5 t / h (inclusive of 0.5 t / h), v2 is taken from 0.5 to 1 t / h (exclusive of 0.5 t / h but inclusive of 1 t / h), and v3 is taken from 1 to 4 t / h (exclusive of 1 t / h but inclusive of 4 t / h).

[0055] In some embodiments, the reaction of aluminum with the alkali solution during activation releases heat, causing the reactor bed temperature to rise. The activation method of this invention establishes a series control relationship between the maximum temperature rise ΔT between the bed layers and the alkali solution flow rate F1, thereby controlling the activation temperature rise through alkali solution flow rate, and thus precisely controlling the aluminum dissolution rate. In some specific embodiments, T... max The temperature of each bed in the reactor can be compared and screened. For example, an online temperature rise module can be added to compare and obtain the highest temperature in each catalyst bed in the reactor.

[0056] To reduce the impact of ambient temperature on the temperature rise ΔT within the reactor, the activation method of the present invention further includes calibrating ΔT using activation exhaust gas from the fixed-bed reactor; in some specific embodiments, an activation tail gas flow meter is installed in the fixed-bed reactor to measure the activation tail gas flow rate F2 of the nickel-aluminum alloy catalyst during the activation process; based on the activation tail gas flow rate F2, the temperature rise ΔT within the fixed-bed reactor is corrected to [0.05×F2 / (T)]. max -T7)]+(T max -T7).

[0057] In some specific embodiments, the nickel content in the nickel-aluminum alloy catalyst involved in the present invention is 40-70 wt%; for example, the nickel-aluminum ratio in the nickel-aluminum alloy catalyst is 58:42.

[0058] In some specific embodiments, the alkaline solution is selected from lithium hydroxide aqueous solution, sodium hydroxide aqueous solution or potassium hydroxide aqueous solution; specifically, the concentration of the alkaline solution is 5 to 50 wt%, for example, 10 wt%, 15 wt%, 40 wt%, 45 wt%, preferably 20 to 35 wt%, for example, 25 wt%, 30 wt%.

[0059] In some specific embodiments, before activating the catalyst, the nickel-aluminum alloy catalyst in the fixed-bed reactor is washed with water for 2 to 4 hours to remove impurities from the surface of the nickel-aluminum alloy catalyst.

[0060] In some specific implementations, once the total amount of dissolved aluminum reaches the required level, the flow of alkaline solution is stopped, and the catalyst is washed with deionized water for 4–8 hours to clean the alkaline solution and residues from the catalyst surface, thus ending the catalyst activation process.

[0061] The present invention also provides a method for the catalytic hydrogenation of 1,4-butynediol to prepare 1,4-butanediol, wherein the hydrogenation catalyst is activated by the above-mentioned activation method before the hydrogenation reaction.

[0062] In some specific embodiments, the conversion of 1,4-butynediol is greater than 99.8%, and the selectivity of 1,4-butanediol is greater than 99.2%.

[0063] The following embodiments use a fixed-bed reactor for the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol as an example to specifically illustrate the activation method of the present invention.

[0064] A certain amount (generally 18t to 20t) of nickel-aluminum alloy catalyst (nickel:aluminum mass ratio of 58:42) is loaded into a fixed-bed reactor. Nitrogen gas is then introduced into the reactor to purge it. After verifying the airtightness, the reactor is washed with water for 2 to 4 hours. Temperature sensors and flow meters are installed at the inlet of the alkali solution in the fixed-bed reactor to measure the inlet temperature T7 and the flow rate F1. Simultaneously, several temperature sensors are installed on the catalyst bed to measure the temperature T at different points within the reactor. The maximum value in each catalyst bed is selected and recorded as T using an online temperature rise module. max .

[0065] Example 1

[0066] 18,616 kg of nickel-aluminum alloy catalyst (nickel-aluminum ratio of 58:42) was loaded into the fixed-bed reactor. Before the catalytic hydrogenation reaction, the nickel-aluminum alloy catalyst was activated with a 28 wt% sodium hydroxide aqueous solution.

[0067] Adding an online temperature rise module to the fixed-bed reactor to screen for T max And calculate △T (△T=T) max -T7, where T7 is the inlet temperature of the alkaline solution), the total dissolved aluminum M of the nickel-aluminum alloy catalyst is related to the activation time t and the temperature rise ΔT in the fixed-bed reactor as follows:

[0068]

[0069] During the activation process, the ΔT calculated by the temperature rise module is used to control the alkaline solution flow rate F1 in series (the alkaline solution initially enters the fixed-bed reactor from the alkaline solution inlet at a flow rate of 2t / h F1); specifically, the following logical relationship is satisfied:

[0070] When the activation process has just begun, and the total amount of aluminum dissolved in the catalyst, M, is between 0 wt% and 12 wt%, then...

[0071] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 2~4t / h;

[0072] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.5t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0073] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.5t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0074] When the total dissolved aluminum M is between 12wt% and 21wt%, then

[0075] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 4~8t / h;

[0076] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.8t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0077] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.8t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0078] When the total dissolved aluminum M is between 21 wt% and 26 wt%, then

[0079] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0080] If ΔT < 8℃, increase the alkali flow rate at a rate of (1.2t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0081] If ΔT > 10℃, reduce the alkali flow rate at a rate of (1.2t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0082] When the total dissolved aluminum M > 26 wt%, the activation endpoint has been reached. Stop the flow of alkaline solution into the fixed-bed reactor, and then wash with demineralized water for 4 hours.

[0083] Example 2

[0084] 18616 kg of nickel-aluminum alloy catalyst (nickel-aluminum ratio of 58:42) was loaded into the fixed-bed reactor. Before the catalytic hydrogenation reaction, the nickel-aluminum alloy catalyst was activated with an alkaline solution (sodium hydroxide aqueous solution) with a concentration of 28 wt%. An activation tail gas flow meter was installed in the fixed-bed reactor to measure the activation tail gas flow rate F2 of the nickel-aluminum alloy catalyst during the activation process.

[0085] Adding an online temperature rise module to the fixed-bed reactor to screen for T max The temperature rise module ΔT is further calibrated using the activated exhaust gas flow rate F2, where ΔT = [0.05 × F2 / (T)]. max -T7)]+(T max The total dissolved aluminum M of the nickel-aluminum alloy catalyst has the following relationship with the activation time t and the temperature rise ΔT in the fixed-bed reactor:

[0086]

[0087] During the activation process, the ΔT calculated by the temperature rise module is used to control the alkaline solution flow rate F1 in series (the alkaline solution initially enters the reactor from the alkaline solution inlet at a flow rate of 2t / h F1); specifically, the following logical relationship is satisfied:

[0088] When the activation process has just begun, and the total amount of aluminum dissolved in the catalyst, M, is between 0 wt% and 12 wt%, then...

[0089] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 2~4t / h;

[0090] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.5t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0091] If ΔT > 10℃, reduce the alkali flow rate at a rate of (0.5t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0092] When the total dissolved aluminum M is between 12wt% and 21wt%, then

[0093] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 4~8t / h;

[0094] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.8t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0095] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.8t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0096] When the total dissolved aluminum M is between 21 wt% and 26 wt%, then

[0097] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0098] If ΔT < 8℃, increase the alkali flow rate at a rate of (1.2t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0099] If ΔT > 10℃, reduce the alkali flow rate at a rate of (1.2t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0100] When the total dissolved aluminum M > 26 wt%, the activation endpoint has been reached. Stop feeding the alkaline solution into the fixed-bed reactor, and then wash with demineralized water for 4 hours.

[0101] Example 3

[0102] 18,616 kg of nickel-aluminum alloy catalyst (nickel-aluminum ratio of 50:50) was loaded into the fixed-bed reactor. Before the catalytic hydrogenation reaction, the nickel-aluminum alloy catalyst was activated with a 28 wt% sodium hydroxide aqueous solution.

[0103] Adding an online temperature rise module to the fixed-bed reactor to screen for T max And calculate △T (△T=T) max -T7, where T7 is the inlet temperature of the alkaline solution), the total dissolved aluminum M of the nickel-aluminum alloy catalyst is related to the activation time t and the temperature rise ΔT in the fixed-bed reactor as follows:

[0104]

[0105] During the activation process, the ΔT calculated by the temperature rise module is used to control the alkaline solution flow rate F1 in series (the alkaline solution initially enters the reactor from the alkaline solution inlet at a flow rate of 2t / h F1); specifically, the following logical relationship is satisfied:

[0106] When the activation process has just begun, and the total amount of aluminum dissolved in the catalyst, M, is between 0 wt% and 12 wt%, then...

[0107] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 2~4t / h;

[0108] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.4t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0109] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.4t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0110] When the total dissolved aluminum M is between 12wt% and 21wt%, then

[0111] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 4~8t / h;

[0112] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.7t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0113] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.7t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0114] When the total dissolved aluminum M is between 21 wt% and 26 wt%, then

[0115] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0116] If ΔT < 8℃, increase the alkali flow rate at a rate of (1.3t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0117] If ΔT > 10℃, reduce the alkali flow rate at a rate of 1.3t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0118] When the total dissolved aluminum M > 26 wt%, the activation endpoint has been reached. Stop the flow of alkaline solution into the fixed-bed reactor, and then wash with demineralized water for 4 hours.

[0119] Example 4

[0120] 18616 kg of nickel-aluminum alloy catalyst (nickel-aluminum ratio of 50:50) was loaded into the fixed-bed reactor. Before the catalytic hydrogenation reaction, the nickel-aluminum alloy catalyst was activated with a 28 wt% sodium hydroxide aqueous solution. An activation tail gas flow meter was installed in the fixed-bed reactor to measure the activation tail gas flow rate F2 of the nickel-aluminum alloy catalyst during the activation process.

[0121] An online temperature rise module was added to the fixed-bed reactor to calculate and screen out T. max The temperature rise module ΔT is further calibrated using the activated exhaust gas flow rate F2, where ΔT = [0.05 × F2 / (T)]. max -T7)]+(T maxThe total dissolved aluminum M of the nickel-aluminum alloy catalyst has the following relationship with the activation time t and the temperature rise ΔT in the fixed-bed reactor:

[0122]

[0123] During the activation process, the ΔT calculated by the temperature rise module is used to control the alkaline solution flow rate F1 in series (the alkaline solution initially enters the reactor from the alkaline solution inlet at a flow rate of 2t / h F1); specifically, the following logical relationship is satisfied:

[0124] When the activation process has just begun, and the total amount of aluminum dissolved in the catalyst, M, is between 0 wt% and 12 wt%, then...

[0125] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 2~4t / h;

[0126] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.4t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0127] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.4t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0128] When the total dissolved aluminum M is between 12wt% and 21wt%, then

[0129] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled to be 4~8t / h;

[0130] If ΔT < 8℃, increase the alkali flow rate at a rate of 0.7t / h to make 8℃ ≤ ΔT ≤ 10℃;

[0131] If ΔT > 10℃, reduce the alkali flow rate at a rate of 0.7t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0132] When the total dissolved aluminum M is between 21 wt% and 26 wt%, then

[0133] If 8℃≤△T≤10℃, the flow rate F1 of the alkali solution should be controlled at 8~12t / h;

[0134] If ΔT < 8℃, increase the alkali flow rate at a rate of (1.3t / h) to make 8℃ ≤ ΔT ≤ 10℃;

[0135] If ΔT > 10℃, reduce the alkali flow rate at a rate of 1.3t / h to ensure that 8℃ ≤ ΔT ≤ 10℃;

[0136] When the total dissolved aluminum M > 26 wt%, the activation endpoint has been reached. Stop feeding the alkaline solution into the fixed-bed reactor, and then wash with demineralized water for 4 hours.

[0137] In the above embodiments, the activation process does not require operator sampling and analysis. After activation, the catalyst is used for the hydrogenation of 1,4-butynediol to prepare 1,4-butanediol. The reaction temperature is 130℃ and the pressure is 30 MPaG. The evaluation results of the catalytic hydrogenation reaction are shown in Table 1 below:

[0138] Table 1

[0139]

[0140]

[0141] Key impurity TBA * The product after the reaction contains impurities such as 2-(4-hydroxybutoxy)-tetrahydrofuran.

[0142] Comparative Example 1

[0143] A certain amount (usually 18t to 20t) of nickel-aluminum alloy catalyst (nickel:aluminum mass ratio of 58:42) is loaded into a fixed-bed reactor. Then, nitrogen gas is introduced into the reactor to purge it. After the airtightness is verified, the reactor is washed with water for 2 to 4 hours.

[0144] A 28 wt% sodium hydroxide aqueous solution was introduced into a fixed-bed reactor to react with the aluminum in the nickel-aluminum alloy catalyst for activation. The operator manually adjusted the flow rate F1 of the alkali solution and took samples for analysis at the reactor outlet every 15 minutes. By analyzing the concentration and flow rate at the alkali inlet and reactor outlet, the rate and total amount of aluminum dissolution were calculated. The rate of aluminum dissolution during activation was controlled at 3 wt% / h to 3.5 wt% / h. When the total amount of dissolved aluminum reached 25 wt%, the introduction of alkali solution into the reactor was stopped, followed by washing with demineralized water for at least 4 hours, at which point activation was complete.

[0145] Comparative Example 2

[0146] A certain amount (generally 18t to 20t) of nickel-aluminum alloy catalyst (nickel:aluminum mass ratio of 50:50) is loaded into a fixed-bed reactor. Then, nitrogen gas is introduced into the reactor to purge it. After the airtightness is verified, the reactor is washed with water for 2 to 4 hours.

[0147] A 28 wt% sodium hydroxide aqueous solution was introduced into a fixed-bed reactor to react and activate the aluminum in the nickel-aluminum alloy catalyst. The operator manually adjusted the flow rate F1 of the alkali solution and took samples at the reactor inlet and outlet every 15 minutes for analysis. By analyzing the concentration and flow rate of the alkali solution at the inlet and outlet, the rate and total amount of aluminum dissolution were calculated. The rate of aluminum dissolution during activation was controlled at 3 wt% / h to 3.5 wt% / h. When the total amount of dissolved aluminum reached 25 wt%, the introduction of alkali solution into the reactor was stopped, followed by washing with demineralized water for at least 4 hours, at which point activation was complete.

[0148] The activated catalyst was used for the hydrogenation of 1,4-butynediol to 1,4-butanediol. The reaction was evaluated at a temperature of 130℃ and a pressure of 30 MPaG. The evaluation results of the catalytic hydrogenation reaction are shown in Table 2 below:

[0149] Table 2

[0150]

[0151] Key impurity TBA * The product after the reaction contains impurities such as 2-(4-hydroxybutoxy)-tetrahydrofuran.

[0152] As can be seen from the data in Tables 1 and 2, the activation method provided by the present invention controls the flow rate of alkaline solution entering the reactor by controlling the temperature rise in series within the reactor, thereby maintaining the activation rate at 3-3.5 wt% / h, realizing the automation of the activation process and accurately controlling the activation endpoint; at the same time, it avoids the problems of low activation efficiency caused by the lag in human operation and the high risk caused by the presence of dangerous hydrogen gas in the sampling process.

Claims

1. A method for activating a nickel-aluminum alloy catalyst, characterized by, The nickel-aluminum alloy catalyst filled in the fixed bed reactor is activated by using alkali liquor; a temperature sensor and a flow meter are arranged at the alkali liquor inlet of the fixed bed reactor to determine the inlet temperature T7 of the alkali liquor and control the flow F1 of the alkali liquor into the fixed bed reactor; The fixed bed reactor is provided with several temperature sensors on the catalyst bed to measure the temperature T of each site, and the maximum value in each catalyst bed is recorded as T max ; During the activation process, the total amount of dissolved aluminum M of the nickel-aluminum alloy catalyst, the activation time t and the temperature rise △T in the fixed bed reactor satisfy the following relationship: M= ； wherein the temperature rise in the fixed bed reactor ΔΤ = T max - T7, T max is the highest temperature in each catalyst bed in the fixed bed reactor; The temperature rise △T in the fixed bed reactor and the flow F1 of the alkali liquor at the alkali liquor inlet satisfy the following relationship: When the total amount of dissolved aluminum M is 0 wt% < M ≤ 12 wt%, then If 8℃ ≤ △T ≤ 10℃, the flow F1 of the alkali liquor is controlled to be 2-4 t / h; If △T < 8℃, the flow of the alkali liquor is increased at a rate of v1 so that 8℃ ≤ △T ≤ 10℃; If △T > 10℃, the flow of the alkali liquor is decreased at a rate of v1 so that 8℃ ≤ △T ≤ 10℃; When the total amount of dissolved aluminum M is 12 wt% < M ≤ 21 wt%, then If 8℃ ≤ △T ≤ 10℃, the flow F1 of the alkali liquor is controlled to be 4-8 t / h; If △T < 8℃, the flow of the alkali liquor is increased at a rate of v2 so that 8℃ ≤ △T ≤ 10℃; If △T > 10℃, the flow of the alkali liquor is decreased at a rate of v2 so that 8℃ ≤ △T ≤ 10℃; When the total amount of dissolved aluminum M is 21 wt% < M ≤ 26 wt%, then If 8℃ ≤ △T ≤ 10℃, the flow F1 of the alkali liquor is controlled to be 8-12 t / h; If △T < 8℃, the flow of the alkali liquor is increased at a rate of v3 so that 8℃ ≤ △T ≤ 10℃; If △T > 10℃, the flow of the alkali liquor is decreased at a rate of v3 so that 8℃ ≤ △T ≤ 10℃; When the total amount of dissolved aluminum M > 26 wt%, the flow of the alkali liquor into the fixed bed reactor is stopped; Wherein, v1 < v2 < v3.

2. The activation method of claim 1, wherein, An activation tail gas flow meter is arranged in the fixed bed reactor to determine the activation tail gas flow F2 of the nickel-aluminum alloy catalyst during the activation process. The temperature rise in the fixed bed reactor ΔT is corrected as [0.05 x F2 / (T max -T7)] + (T max -T7) according to the activated tail gas flow F2.

3. The method of activation of claim 2, wherein, The proportion of nickel in the nickel-aluminum alloy catalyst is 40-70 wt%.

4. The activation method of claim 3, wherein, v1 is taken from 0.2-0.5 t / h, v2 is taken from 0.5-1 t / h, and v3 is taken from 1-4 t / h.

5. The activation method of claim 4, wherein, The alkali liquor is selected from lithium hydroxide aqueous solution, sodium hydroxide aqueous solution or potassium hydroxide aqueous solution.

6. The activation method of claim 5, wherein, The concentration of the alkali liquor is 5-50 wt%.

7. The activation method of claim 6, wherein, The concentration of the alkali liquor is 20-35 wt%.

8. The activation method according to any one of claims 1 to 7, characterized in that, Before activation, the nickel-aluminum alloy catalyst in the fixed bed reactor is washed with water.

9. The activation method of claim 8, wherein, The nickel-aluminum alloy catalyst is washed with water for 2-4 h.

10. The activation method of claim 8, wherein, After stopping the flow of the alkali liquor into the fixed bed reactor, the catalyst bed is washed with desalted water.

11. The activation method of claim 10, wherein, The catalyst bed is washed with desalted water for 4-8 h.

12. A process for the catalytic hydrogenation of 1,4-butynediol to 1,4-butanediol, characterized in that, Before performing the hydrogenation reaction, the hydrogenation catalyst is activated by using the activation method of any one of claims 1-11.

13. The method of claim 12, wherein, The conversion rate of 1,4-butynediol is greater than 99.2%, and the selectivity of 1,4-butanediol is greater than 98.5%.

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