A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
August 17th, 2016
The study of methods to generate on-demand hydrogen for fuel cells continues to grow in importance. However, systems to measure hydrogen evolution from the reaction of chemicals with water can be complicated and expensive. This article details a simple, low-cost, and robust method to measure the evolution of hydrogen gas.
The overall goal of this method is to provide a simple, easy setup for measuring the evolution of hydrogen gas from a chemical reaction. This method can help researchers in the field of hydrogen generation to measure the efficiency of specific catalysts of materials in generating hydrogen from reactions with aqueous solutions. The main advantages of this technique are that it is simple, low-cost, and robust.
Before beginning the procedure, add water to a glass bowl until it is approximately 3/4 full. Then, place the bowl on a temperature-controlled stirrer hotplate set to 50 degrees Celsius. When the water reaches 50 degrees Celsius, place a 50-milliliter round-bottom flask containing five milliliters of de-ionized water into the bowl such that the level of the water in the bowl is well above the level of the water in the flask.
Set a thermometer into the neck of the flask to monitor the temperature. After equilibration, the temperature of the water in the flask is usually approximately five degrees Celsius lower than the set point on the hotplate. When the temperature of the water in the flask remains constant over a 10-minute period, fill a beaker with de-ionized water and place an empty beaker onto a data-logging balance.
Next, use a plastic sheet to construct a bridge for transferring water from the spout of the water beaker to the empty beaker on the data-logging balance, taking care that the plastic bridge is not in physical contact with the beaker on the data-logging balance. When the bridge is in place, fill a 500-milliliter measuring cylinder with de-ionized water and cover the opening of the cylinder with a gloved hand. Invert the cylinder and place it into the beaker of water, such that the opening of the measuring cylinder is just below the surface of the water.
Then, clamp the cylinder to a retort stand fitted with two bosses to hold the cylinder in place. Adjust the position of the beaker such that the spout is in contact with the plastic bridge. Then, carefully raise the measuring cylinder to allow a release of water and in ingress of air to keep the level of the air in the measuring cylinder consistent at the beginning of each experiment.
Insert the non-ground glass joint end of a modified adapter into a length of tubing and carefully wrap parafilm around the connection between the joint and the tubing. Insert the end of the tubing into the measuring cylinder and add water to the beaker to make sure that the excess water runs off onto the balance. Confirm that the data-logging balance does not read zero.
Then, use a separate balance to weight out the appropriate amount of silicon into a small glass vial. Now, place a 50-milliliter round-bottom flask containing 5 milliliters of sodium hydroxide solution into the water bath, such that the level of the water in the bath is well above the level of sodium hydroxide in the flask. Place a thermometer into the neck of the flask and allow the solution to equilibrate for 10 minutes.
During the equilibration, open a new spreadsheet in the appropriate spreadsheet software package and open the data collection software. Load the appropriate data-logging software file. Then, just before the end of the 10 minutes, select Activate and click on Normal Mode to begin logging the data in the spreadsheet software package.
At the end of the 10-minute equilibration period, rapidly invert the glass vial and deposit the silicon directly into the sodium hydroxide solution. Quickly place the ground-glass joint of the adapter into the neck of the round-bottom flask and zero the balance. After 10 minutes, press the backspace key to stop the data logging and select Quit.
Save the file in the spreadsheet software package. Remove the adapter from the round-bottom flask and add water to quench the reaction. The solid residue in the flask can then be isolated for further analysis.
To investigate the reproducability of the experimental setup, varying masses of silicon are reacted with aqueous sodium hydroxide solutions to generate hydrogen. In these representative experiments, there was very little deviation in the total hydrogen yields, and the hydrogen generation rates between the reactions, with a greater level of deviation observed within the periods of induction. In this representative sub-optimal experiment, the low flow of hydrogen between 200 and 800 seconds resulted in a buildup of drips due to the surface tension of the water at approximately 400 and 710 seconds.
Though drips do not affect the calculation of the maximum hydrogen generation rate, they could have an effect on the total hydrogen yield if, for example, the the measurement was stopped before the drips fell. Once mastered, a hydrogen measurement can be conducted in 30 minutes if the technique is performed properly and the material are catalysts to sufficiently reactive. While attempting this procedure, it's important to remember that it will not work for very rapid or very slow flows of gas.
For our next procedure, the residual material can be isolated, and other methods, like X-Ray Diffraction, infrared spectroscopy, and X-Ray photoelectron spectroscopy, can be performed to investigate the mechanism of hydrogen generation from the materials used. After watching this video, you should have a good understanding of how to measure the hydrogen evolution from the reactions of materials with aqueous solutions using a data-logging balance. Don't forget that working with hydrogen can be hazardous, and that precautions, such as always performing the procedure in a fume hood, should be taken.
Overview
This article presents a simple and cost-effective method for measuring hydrogen gas evolution from chemical reactions. The technique is designed to assist researchers in evaluating the efficiency of catalysts in hydrogen generation.
Key Study Components
Area of Science
- Hydrogen generation
- Catalysis
- Chemical reactions
Background
- Hydrogen is a promising fuel source for fuel cells.
- Measuring hydrogen evolution can be complex and costly.
- Simple methods can enhance research efficiency.
- This study aims to simplify the measurement process.
Purpose of Study
- To provide a straightforward method for measuring hydrogen evolution.
- To facilitate research on catalyst efficiency.
- To reduce costs associated with hydrogen measurement techniques.
Methods Used
- Setup includes a water bath and data-logging balance.
- Equilibration of solutions is performed before measurements.
- Silicon is reacted with sodium hydroxide to generate hydrogen.
- Data is logged for analysis of hydrogen production rates.
Main Results
- The method allows for reproducible measurements of hydrogen yields.
- Minimal deviation in hydrogen generation rates was observed.
- Surface tension effects were noted during hydrogen flow.
- Results indicate the method's reliability for catalyst evaluation.
Conclusions
- This method is effective for measuring hydrogen evolution.
- It can be performed in approximately 30 minutes with proper technique.
- Safety precautions are essential when working with hydrogen.
Frequently Asked Questions
Executive Industry Relevance
Accurate quantification of hydrogen evolution is critical for evaluating catalyst performance in on-demand hydrogen generation systems for fuel cell applications. This low-cost, robust method enables reproducible measurement of hydrogen yield, generation rate, and induction period, supporting early-stage catalyst screening and mechanistic de-risking. By providing quantitative, time-resolved data, it enhances predictive confidence in material selection for hydrogen production workflows.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of catalytic materials for hydrogen generation efficiency, supporting target validation in energy-related bioprocesses.
- Operational Value: Uses accessible equipment (water bath, balance, tubing) to standardize hydrogen measurement across laboratories.
Screening & Assay Development
- Scientific Value: Generates quantitative dependent variable measurements (hydrogen yield, flow rate) for comparing catalytic activity across material libraries.
- Operational Value: Adaptable measuring cylinder size and balance resolution allow scalability for high-throughput screening of catalysts.
Translational & Preclinical Research
- Scientific Value: Supports mechanistic de-risking by correlating material properties with hydrogen evolution profiles, informing translational biomarker alignment in biohybrid systems.
- Operational Value: Enables reproducible, low-variance measurements that improve confidence in preclinical advancement decisions for hydrogen-producing biologics or hybrids.
Pipeline & Workflow Integration
This method fits within the discovery continuum from early catalyst screening to lead identification, providing quantitative gas evolution data that informs go/no-go decisions before preclinical investment.
- Discovery Biology: Supports hypothesis testing of catalytic mechanisms by measuring hydrogen output as a functional readout of material activity.
- Screening: Delivers assay-ready, reproducible hydrogen evolution data with minimal deviation across replicates, enabling reliable compound or material evaluation.
- Analytics: Provides time-resolved mass change data deducible to hydrogen generation rate, total yield, and induction period for comparative analysis.
- Translational Research: Connects discovery-phase catalyst evaluation to preclinical continuity by establishing reliable hydrogen output benchmarks.
- Enterprise Reuse: Establishes a reusable, low-cost platform for hydrogen measurement that can be shared across teams working on PEM fuel cell integration or biohydrogen systems.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in catalyst selection through quantitative, reproducible hydrogen evolution metrics.
- Operational Value: Ensures standardization and reproducibility via simple setup and data-logging balance integration.
- Strategic Value: Improves capital efficiency by reducing reliance on expensive gas chromatography or mass spectrometry for initial screening.
- Portfolio Impact: Enables risk-adjusted prioritization of catalysts based on hydrogen yield and rate data, reducing late-stage failure in hydrogen-dependent bioprocesses.
Implementation Considerations
- Requires basic laboratory expertise in solution preparation, temperature control, and balance operation.
- Needs temperature-controlled water bath, data-logging balance, glassware, tubing, and spreadsheet software for data collection.
- Demands cross-team standardization of measurement duration, equilibration time, and drip correction protocols for consistent results.
- Involves adaptation considerations for different hydrogen volumes and flow rates via cylinder size and balance resolution adjustments.
- Includes practical limitations: unsuitable for very rapid or very slow gas flows where measurement accuracy may be compromised by surface tension effects or timing constraints.
