Hydrogen Gas Generator vs. Hydrogen Gas Cylinders

[mattmullaney]

Good Morning,

I'm considering going through the process of making a capital acquisition of a hydrogen generator. I feel that there's not much doubt that these generators are far safer, easier to deal with and less expensive in the long term than using hydrogen gas cylinders. In my own experience, I used one that I purchased for a bit more than four years (to deliver FID fuel and carrier gas) without any issues--I did perform routine maintenance as required on that unit.

My question is this...others have told me that their recent experiences were less-than-desirable with the hydrogen generators they purchased, and they uniformly chose to return to using hydrogen gas cylinders. Please, could you folks let me know of your experience(s) with hydrogen generators with an eye toward longevity and lend your opinion to whether or not you would purchase one (again) if you found yourself without one in your lab?

My thanks to you all, in advance!

[gstaepels]

I am using hydrogen generators for the last 12 years, and my experience is in all positive. You haven't mention the reason why other turn back to cylinders. I wonder why changing. Nowadays GC are equipped with sensors, hydrogen generators have safety features, such as switching off when a leak is detected etc...
So, at this moment, I am very pleased with the decision to use generators.
Take care.
Gilbert

[mattmullaney]

Hi Gilbert--my thanks to you. The most common complaint I've heard is relatively early (three years or less) failure of the cell. Others I'm not as inclined to list.

Please, are there any other comments--and again, my thanks to you (all), in advance.

[Peter Apps]

Going back several years I had a cell failure, and a new cell was about the same cost as a new generator, and wiped out all the savings on cylinder gas. The electrolyte needs topping up with HPLC grade water, or flushing and replacing quite frequently if you use lower grade water. This was no problem because we had a water purifier in the HPLC lab, but it is an extra expense if you do not have a purifier already.

If you have a UPS system for the GCs then you need to put the H2 generator on it as well.

Peter

[mattmullaney]

Hey Peter,

Agreed on the cost of a new cell (if not covered by extended warranty, I suppose, if those are offered?), and the idea that all of the savings you experienced were wiped out is a sobering one, and not lost on me. On the plus side, we have in-house water purification to ASTM Type 1 grade already in place, as well as the UPS.

Always there are the pros-and-cons in life.

My thanks, sir, for your response.

Please, are there others willing to weigh in?

Regards to All.

[Chenosuke]

Hi,

Peter is 100% correct about the cell failure wiping out savings. Also, I had a generator's power supply fail on me in a very short window when the UPS was out for servicing. So I agree, that unit MUST be on a UPS at all times. The balance is safety and convenience though. A couple hydrogen cylinders are very dangerous to have in the lab. In fact, most safety regulations dictate that they be stored outside in a controlled area. If you haven't already got the infrastructure in place, then you have to set up a route for the gas tubing running from the outside to your instruments in the lab. That also means more possibility for leaks, more points to check for said leaks, and also you have to ensure that your setup is prepared to deal with any condensation in the line along the way.

It is more convenient to have a generator on (or under) the bench inside with a short line to your instruments. Proper maintenance of the unit is key, and hopefully you don't get a bad cell. If you do, hopefully, it fails while under warranty. In my opinion, it is worth the risk to invest in one.

Chen.

[Yama001]

I work in a lab where maintenance is totally neglected until the techs cannot get anything out of the instruments. In this environment, cylinders are easier to work with.

[Consumer Products Guy]

We've used a hydrogen generator for 6 years to produce FID fuel gas for several GCs and H2 carrier gas for one GC. We have a Parker 500 ml capacity unit, and have pure water here, haven't had any breakdowns or service. We manually fill/top off ours with water once per week.

[mattmullaney]

First and Foremost, My Thanks and Appreciation to Everyone That Responded.

@ Consumer Products Guy...my idea is to purchase a unit that delivers a hydrogen gas capacity similar to that you speak of above...to initially provide carrier and fuel to one GC-FID, and eventually two. It's overkill on the delivery capacity, but this is what I'd planned out.

@ Yama001...Wow, and I do see your point. Where I'm at, the onus of the maintenance is on me, but there may be a time when this would not be the case...and that would not be pretty. I'll do well to keep this in mind.

@ Chenosuke and Peter...I've heard that a hydrogen generator purchased by another division of my firm physically near mine failed after three years (my own experience with the one I bought was better...I observed more than four problem-free years before moving on), so what you both say is also not lost on me. Heard similar observations from other sources...don't know if the three-year figure is coincidental or not, but it's a number I'm hearing a lot. Naturally, I'd much prefer an experience such as Gilbert's above or Consumer Product Guy's below. As you well note...there's risk.

Agreed also with regard to the safety aspect--we've done very well on that score, we've a proper ventilated gas cabinet with a minimal tubing run to the gas purifier train and then to the GC. To be fair, that was plumbed in before I met up with my current organization. And, UPS would be in place...and a necessity in my mind.

Overall, I think I'll go ahead and write a justification for the purchase (more reason than only the acquisition of a hydrogen generator to do this, it's good practice for another time later on when I'm trying to do a capital purchase with the firm I'm working for)...and I'll come back here and let everyone know what pans out.

[Jake]

I'm in a relatively high throughput lab, where processing 1000+ samples per day on five GCs is not uncommon. I can't imagine doing this without hydrogen generators. Since uptime/throughput is a primary concern, we have service contracts on everything. We have three Parker hydrogen generators and are completely hydrogen-tank-free. We've had an H2-500 for 6 years. The cell has failed twice. But under service contract Parker's been great to deal with. Both times they've cross-shipped a temp. unit while ours was being repaired. We've had an H2-800 for almost 4 years - not a single problem. It's been a great unit. And we just recently acquired an H2-1300 (6 months; not a problem). Operation/maintenance for all is simple. Use good quality water (we just us Milli-Q), and change the di-ionizing bags every 6 months. That's it. While there are safeguards to prevent issues, an engineer strongly suggested not running them out of water. That's easy enough to do. We just fill them all every night before we go, and they make it through the weekend.

Hope this helps.

[mariareese]

@Peter: I also had the water purifier in HPLC lab, it work properly! In my knowledge HPLC is high performance liquid chromatography. It uses advanced technique that can separate a mixture of compounds. This technique is used in biochemistry chemistry to identify, and purify the individual components of the mixture, particularly in the separation of amino acids.

___________________
video colposcope

[itspip]

I'm in a similar situation. Our H generator failed and some in the company want to look into switching back to cylinders. Any points that the community could give me to help the decision to repair or return to cylinders?

[GOM]

A former manager of mine asked if we could replace Helium cylinders with a generator !!

I pointed him to the Sun

Sometimes you just can't shake your head enough

Regards

Ralph

[Jake]

Thought I'd update this - our H2-500 failed again, for the third time (3 failures in a about 7 years). There was still a month on its service contract, so it was repaired again for free. Since we barely use it now, we didn't renew the service contract. We'll just let it die with the next issue. Clearly a major design and/or quality issue with the cell of the H2-500. Both our H2-800 and H2-1300 remain in near 24/7 high use without a single issue. Very happy with both those units, and wouldn't hesitate to buy another.

[James_Ball]

We have been using the H2 generators for about 6 years now. The first Parker unit lasted about 4 years it was the H2-800 unit. I think a small leak caused it to work too hard, and killed it. We replaced it with two Proton on Site 600ml/min units and for a year we were barely keeping pressure on the line. I found a leaking valve and replaced it and now we only refill the water once a week. These supply the entire building with carrier for about 10 GCs and fuel for 6 FIDs. Since we also have the tank farm outside we keep a cylinder of Hydrogen online but have the pressure regulator set 20psi below the line pressure with a check valve on the line, so that if the generator fails the line pressure will only drop from 70psi down to 50psi and the cylinder will take over as backup. This also helps if we need to do maintenance on the units, to supply gas while they are offline.

I think we paid for both of the new units in one year with the savings over what the cylinders cost, so even if they go out after three years we have made money on them. The new units use a molecular sieve moisture trap instead of the palladium membrane, which means a little more maintenance but less expense of the units. The only gas we have to keep in cylinders now is Helium for the GC/MS units, if I can ever make them tune with Hydrogen I will switch them over too.