A method for directly evaluating catalyst life in a hydrogen release process

Abstract

The application discloses a method for directly evaluating catalyst life in a hydrogen release process, and is applied to a continuous dehydrogenation reaction system, which comprises a storage tank, a feed pump, a preheater, a reactor and a hydrogen purifier, and comprises the following steps: 1) preheated hydrogen-rich liquid material enters the reactor to carry out a hydrogen release reaction, when the temperature of the reactor reaches 150 DEG C, timing is started, and data is independently collected in multiple temperature intervals, and the collected data comprises a reaction temperature and a reaction time; 2) the material at the outlet of the reactor is separated into a gas phase and a liquid phase after passing through the hydrogen purifier, real-time detection and recording are carried out on the flow of gaseous hydrogen; 3) the accumulated timing and hydrogen flow data of each temperature interval are simultaneously stored in a data storage; and 4) a hydrogen flow curve graph in different temperature intervals is drawn with time as the horizontal coordinate and hydrogen flow as the vertical coordinate. Through the method, the attenuation of catalyst performance life can be directly and simply reflected by the instantaneous release amount of hydrogen.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst evaluation, and in particular to a method for directly evaluating catalyst life in a hydrogen release process. Background Art

[0002] In current fixed-bed catalytic chemical reactions, there is relatively little technology development that can simultaneously evaluate catalyst performance during the reaction. This is especially true for the relatively simple catalytic reaction based on organic liquid hydrogen storage technology, such as dehydrogenation reactions at the kilogram level or above within the reactor. For this reaction, there is currently no method for simultaneously evaluating the catalyst life performance within the reactor. This situation results in users having insufficient understanding of the actual situation within the reactor and being unable to keep track of the true condition of their core catalyst, leading to anxiety about catalyst performance degradation. If the catalyst performance life within the fixed bed could be monitored and evaluated in real time, it would greatly promote reaction process research and the evaluation of catalyst life indicators, eliminating users' concerns about catalyst life issues. Summary of the Invention

[0003] The object of the present invention is to provide a method for directly evaluating the life of a catalyst during a hydrogen release process, which can intuitively reflect the catalytic reaction performance of a fixed catalyst.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] A method for directly evaluating catalyst life during hydrogen desorption is applied to a continuous dehydrogenation reaction system. The continuous dehydrogenation reaction system includes a storage tank, a feed pump, a preheater, a reactor, and a hydrogen purifier, and includes the following steps:

[0006] 1) The hydrogen-rich liquid material is pumped from the storage tank via a feed pump and fed into a preheater. After being preheated in the preheater, the hydrogen-rich liquid material enters the reactor for a hydrogen release reaction. When the reactor temperature reaches 150°C, the timing starts. The timing is divided into multiple temperature intervals and data is collected independently. The collected data includes reaction temperature and reaction time. The time interval of the sampling data in each temperature interval is the same or different.

[0007] 2) The material at the reactor outlet is separated into gas and liquid phases after passing through a hydrogen purifier and enters their respective pipelines. The liquid hydrogen-poor carrier enters the storage tank, and the hydrogen end is supplied to the user. The flow rate of gaseous hydrogen is detected and recorded in real time, with a recording interval of 10-300 seconds;

[0008] 3) The accumulated timing of each temperature interval in step 1) and the hydrogen flow rate data collected in step 2) are stored in a data memory at the same time, and the timing time points of the temperature interval correspond to the collection time points of the hydrogen flow rate one by one:

[0009] 4) with time as the horizontal coordinate, hydrogen flow as the vertical coordinate, the hydrogen flow curve in different temperature intervals is drawn, and the reaction progress of the catalyst is judged by the change of hydrogen flow.

[0010] As a specific embodiment, in step 1), the temperature interval is divided into three, which are the first timing interval: 150℃≤T≤190℃, the second timing interval 190℃<T≤220℃; the third timing interval: 220℃<T≤250℃.

[0011] As a specific embodiment, a hydrogen mass flow meter is installed at the outlet of the hydrogen purifier for real-time detection of hydrogen flow.

[0012] As a specific embodiment, a temperature sensor, a timer and a detection controller are installed on the reactor, and the detection controller is used to store detection data.

[0013] As a specific embodiment, the set temperature of the preheater is 170℃.

[0014] The method provided by the application can directly and simply reflect the attenuation of the performance life of the catalyst in the reactor through the instantaneous release amount of hydrogen, and the hydrogen release reaction in the organic liquid hydrogen storage technology is a single reversible dehydrogenation reaction, so the gas flow at the outlet of the reactor can represent the instantaneous condition of the reaction without the introduction of other impurity gases, the reaction progress can be judged according to the feed amount, and the performance life of the catalyst can be directly and intuitively evaluated. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 The hydrogen flow curve in different temperature intervals. DETAILED DESCRIPTION

[0016] The technical solutions of the application will be further described below with reference to specific embodiments.

[0017] A method for directly evaluating the life of a catalyst in a hydrogen release process is applied to a continuous dehydrogenation reaction system, which comprises a storage tank, a feed pump, a preheater, a reactor and a hydrogen purifier, and comprises the following steps:

[0018] 1) The hydrogen-rich liquid material is pumped out from the storage tank through the feed pump and sent into the preheater, and the preheater is set to a temperature of 170℃;

[0019] 2) The hydrogen-rich liquid material preheated by the preheater enters the reactor for hydrogen release reaction, and the temperature of the reactor is set in the range of 180°C-220°C; when the temperature of the reactor reaches 150°C, a timer starts timing, and the timer timing is divided into three temperature intervals for independent data collection. The collected data includes reaction temperature and reaction time. The time interval of the sampling data in each temperature interval is the same or different. Specifically, the three temperature intervals are: a first timing interval: 150°C ≤ T ≤ 190°C, a second timing interval: 190°C < T ≤ 220°C; and a third timing interval: 220°C < T ≤ 250°C (this interval is the over-temperature timing interval);

[0020] 3) The material at the reactor outlet is separated into gas and liquid phases after passing through a hydrogen purifier and enters their respective pipelines. The liquid hydrogen-poor carrier enters the storage tank, and the hydrogen end is supplied to the user. A hydrogen mass flow meter is installed on the gaseous hydrogen delivery pipeline to detect and record the flow of gaseous hydrogen in real time, with a recording interval of 10-300 seconds;

[0021] 4) The accumulated timing of each temperature interval in step 2) and the hydrogen flow rate data collected in step 3) are stored in a data memory at the same time, and the timing time points of the temperature interval correspond to the collection time points of the hydrogen flow rate one by one:

[0022] 5) With time as the horizontal axis and hydrogen flow rate as the vertical axis, draw a hydrogen flow rate curve in different temperature ranges, see Figure 1 As shown in the figure, the hydrogen flow rates in three different temperature ranges are divided into three curves in the same figure. As time goes by, the amount of hydrogen generated at the instantaneous time point will decrease, which can intuitively display the catalytic performance of the current catalyst. The reaction progress of the catalyst can be judged from the curve graph by the change in hydrogen flow rate. Because the dehydrogenation reaction is an endothermic reversible single reaction, the most core influencing factor is temperature. Therefore, from the curve graph we can see how the catalyst life changes with time and reaction temperature.

[0023] Here, a temperature sensor, a timer, and a detection controller are installed on the reactor, and the detection controller is used to store detection data.

[0024] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there may be changes in the specific implementation methods and application scopes. The contents of this specification should not be understood as limiting the present invention.

Claims

1. A method for directly evaluating catalyst life during hydrogen release, applied to a continuous dehydrogenation reaction system, wherein the continuous dehydrogenation reaction system comprises a storage tank, a feed pump, a preheater, a reactor, and a hydrogen purifier, characterized in that: The following steps are involved: 1) The hydrogen-rich liquid material is pumped from the storage tank through a feed pump and fed into the preheater. The hydrogen-rich liquid material preheated in the preheater enters the reactor for hydrogen release reaction. When the reactor temperature reaches 150°C, timing begins. The timing is divided into multiple temperature intervals and independently collects data. The collected data includes reaction temperature and reaction time. The time interval of the sampling data in each temperature interval is the same or different. Specifically, the temperature intervals are divided into three, namely, the first timing interval: 150°C ≤ T ≤ 190°C, the second timing interval: 190°C < T ≤ 220°C; and the third timing interval: 220°C < T ≤ 250°C. 2) The material at the reactor outlet is separated into gas and liquid phases after passing through the hydrogen purifier and enters their respective pipelines. The liquid hydrogen-poor carrier enters the storage tank, and the hydrogen end is supplied to the user. The flow rate of gaseous hydrogen is detected and recorded in real time, with a recording interval of 10-300 seconds; 3) The accumulated timing of each temperature interval in step 1) and the hydrogen flow rate data collected in step 2) are stored simultaneously in a data memory, with the timing time points of the temperature interval corresponding to the collection time points of the hydrogen flow rate; 4) Using time as the horizontal axis and hydrogen flow rate as the vertical axis, draw a hydrogen flow rate curve in different temperature ranges, and judge the reaction progress of the catalyst by the change in hydrogen flow rate.

2. The method for directly evaluating catalyst life during hydrogen desorption according to claim 1, characterized in that: A hydrogen mass flow meter is installed at the outlet of the hydrogen purifier for real-time detection of the hydrogen flow rate.

3. The method for directly evaluating catalyst life during hydrogen desorption according to claim 1, wherein: The reactor is equipped with a temperature sensor, a timer and a detection controller, and the detection controller is used to store detection data.

4. The method for directly evaluating catalyst life during hydrogen desorption according to claim 1, wherein: The set temperature of the preheater is 170°C.

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