If you would like to contact us please send an email to Alternatively please use the form below.

Cquestrate Limited is a private limited company registered in England & Wales. Company no. 06626549. The company’s registered address is Cquestrate Limited, 73 Southern Road, Thame, Oxon, UK, OX9 2ED.


23 people have left a comment

Alberto says: July 22nd, 2009

Please let me give you some Thermodynamics topics concerning your idea, how you talk about it.

1-You mine CaCO3 (let’s say 1 tonn) … spending energy…
2-You heat CaCO3 to extract CaO (you’ll need to heat to over 900°C… a lot of energy, at least 6 MegaJoules per 100g)
3-Once heat, CaCO3 will absorb 176 KJoules/100g (about 1760 Megajoule for 1 tonn) to decompose to CaO and CO2… producing CO2
4-…now you propose to use this CaO to trap some new CO2 on water… some CO2 that will be less than you’ve already spent!!!

First problem: what you have been doing is get free one CO2 molecule to absorb another CO2 molecule… not so smart…
Second problem: In order to decompose CaCO3 you’ll have to spend 1760 MJ or energy per 1 tonn of CaCO3, the equivalent you might produce burning 53 kg of carbon and producing 196 kg of CO2… all of that to trap 440 kg of CO2… and I didn’t count the energy needed for heating and all other operations!!!

Short: you are proposing to take a substance, spend a lot of energy (and produce a lot of CO2) to extract its CO2 and send it into the atmosphere so that you’ll be able to re-trap some of the CO2 you have just been producing… on thermodynamics, it doesn’t make sense…


Ps: as you wanted numbers…
1-Energy needed to calcinate CaCO3: 176 Kjoule/100g CaCO3, equivalent to producing AT LEAST 19,6 g of CO2; heating CaCO3 to 900°C: 6 MJoule/100g CaCO3 theoric (based zero loss efficiency)
2-CO2 generated during the production of lime: 44g CO2 from 100g CaCO3 decomposition, 19.6 g CO2 due to you need to give energy to decompose 100g CaCO3… at least 180g CO2 for heating of 100g CaCO3 based on Carbon rich fuel
3-CaCO3 calcination is a process that is thermodynamically possible only at very high temperature (900°C or more); no way of proceeding without heating.

Jem Cooper says: February 9th, 2010

The plan only makes sense if you capture and sequester the carbon dioxide produced in the calcination step.

Adam Pelling-Deeves says: April 21st, 2010


I’m a freelance video editor and producer based in Oxford and I thought it would be a good idea to introduce myself in case my help in video work is something that would be of any use to you in the future.

Working predominantly in the world of corporate video, I’ve created videos for training, conferencing, marketing and web content for a wide variety of clients since 1997.

I’m currently located just a couple of hundred meters from Oxford station and have my own Final Cut Studio suite. For more information or to have a look at some of my work you can visit


Jeremy says: July 11th, 2010

Re: calcium oxide to precipitate calcium carbonate to sequester carbon dioxide

Dear Dr. Kruger,

I was wondering if I could ask you about a project I am designing for carbon sequestration. I am currently a rising junior in high school in Pennsylvania, USA. This summer I am participating in an environmental science program at the University of Pennsylvania for high school students. Seven students are in the program, and as part of the program we are given the opportunity to design our own laboratory research project. We have three weeks to perform this experiment, but can continue working on it during the year if we would like.

I have been reading about carbon sequestration, and have been particularly interested in the difficulty in getting rid of the sequestered carbon. It occurred to me that if factory exhaust fumes can be percolated through water, it may be possible to precipitate out the CO2 as calcium carbonate (similar to what shellfish slowly do to create limestone). This calcium carbonate could then be used commercially for cement, paper, etc. As a result, CO2 would be sequestered and then “disposed of” as a useful material.

I was very excited to read about your approach to use calcium carbonate precipitation to reduce ocean acidification. Upon reading your methods from the web, it wasn’t clear to me how easy it would be to use the calcium oxide to react with the CO2 in water to precipitate out the calcium carbonate. I was therefore wondering if you could be so kind to give me a better understanding of this process, and if it might be something I could do in a laboratory.

As I only have a short time to do this experiment, and I am just a high school student, I was wondering if I could propose to you my experimental design to see if you think if it makes sense. If not, I surely would appreciate any insights you might have for a better experiment.

At present, my experimental design would be as follows: My CO2 source would be dry ice. I would place the dry ice in a container of water (the pH, salinity, etc. would be as per your recommendations). I would then add commercially available calcium oxide (again, as per your recommendations). I have read about the heat and fumes generated from this process, and would be able to work in a hood. I would then quantitate the amount of calcium carbonate generated from the amount of calcium oxide and CO2 used. I understand from your article that although CO2 and energy would also be needed to create the calcium oxide that I commercially buy (or create as per your process), the net CO2 sequestration would still be positive.

I’m sure you are very busy, so I can certainly understand if you don’t have time to help me. However, if you could be so kind to guide me as to the potential of my idea, and the feasibility of my experimental design, I would be greatly appreciative. In addition, if you have any other ideas as to how a high school student like myself could perform a useful experiment to explore this important topic I would be very thankful.

Thank you for your help,

Jeremy says: July 11th, 2010

I made a typo when giving my email address. Attached is the correct email addresss.
Thank you,

Player Profiles says: October 30th, 2010

You you could change the page title Cquestrate : Contact to more generic for your content you make. I loved the the writing yet.

R.Mani says: August 24th, 2011

We are in the process of setting up a foundry and as a part of backward integration to install a power plant and cement industry with a capacity of 1 Milllion tons.
Since our project site is near harbor, we thgouht of importing good quality limestone to compete in the market both with quality and cost.
Could you please direct a suitable source with cost to reach Chennai port (South India) where we are going to haev our site.
Emperor group

Tubabillist says: August 19th, 2013

時計 セイコー seiko メンズ シチズン 腕時計 レディース時計 ソーラー 電波 gps セイコー 男 腕時計 ブランド 時計 ブランド 人気 腕時計 激安腕時計 ソーラー レディース 時計 ブランド レディース 時計 レディース 通販 セイコー 時計 レディース腕時計 高校生 人気 レデイース 時計ソーラー 腕時計 おすすめ 腕時計 検索 セイコーメンズ時計 腕時計 最新高校生 腕時計 人気 レディース 腕時計casio 時計 レディース gshock 電波 ソーラー モデル 腕時計 レディース 腕時計 ソーラー レディス 時計 ブランド 価格 時計 ランキング dee and ricky g shock 腕時計 ブランド 比較

フルラ 時計 says: November 28th, 2013


kids ugg boots cheap says: November 28th, 2013

For a large amount of information regarding on ugg slippers canada sale look for it in

Canada Goose Herrejakke says: November 28th, 2013

Here is farther more about nike roshe run mens blue by using

herren jacken woolrich says: December 31st, 2013

I’ve been browsing on-line more than three hours today, but I by no means found any fascinating article like yours. It’s lovely price enough for me. In my opinion, if all site owners and bloggers made excellent content as you did, the net can be much more helpful than ever before. “Nothing will come of nothing.” by William Shakespeare.

バッグ各種 says: March 23rd, 2014


louboutin replica flats for sale says: March 24th, 2014

basketball jerseys at wholesale wholesale sportswear cheap hockey jerseys cheap authentic nfl football jerseys with discount price cheap jerseys cheap nfl jerseys nike cheap nfl jerseys cheap jerseys – buy wholesale authentic nfl & nba jerseys online nba jerseys cheap buy cheap jerseys online from china, wholesale price & free shipping wholesale jerseys cheap nfl jerseys online hot sale, wholesale price & free shipping best wholesale nfl jerseys online, welcome shop now cheap mesh football jerseys cheap mlb jerseys on sale from china cheap authentic jerseys wholesale football jerseys wholesale jerseys china wholesale jerseys china cheap football jerseys wholesale
louboutin replica flats for sale

tiffany charm says: March 29th, 2014

The developer keeps the complete asset ownership. Resale is often hard. In contrast to Fractional Possession there’s no capital growth only capital cost..
tiffany charm

how to tell if its a real tiffany lamp says: March 29th, 2014

Hermes birkins are created by the huge-stop leather-based items and entirely prepared to don producer Hermes. These bags are so exclusive and unique that their quantity can initiate from $7500 and can reach up to six digit costs. So, these Hermes birkins could be taken because the thing of luxurious that can enable in producing you appear numerous from other folks..
how to tell if its a real tiffany lamp

Dominic says: July 30th, 2014

On another call how much ibuprofen is in advil Accurately records and enters all required

James Cameron says: October 7th, 2014

Want more clients and customers? We will help them find you by you on the 1st page of Google. Email us back to get a full proposal.

domain says: October 13th, 2014

Very great post. I just stumbled upon your blog and wanted to mention that I have really enjoyed surfing around your blog posts.
In any case I will be subscribing to your feed and I
am hoping you write again very soon!

kb says: May 29th, 2017

Hi every one,
We are going to southern Turkey in the region of Bodrum for 4 monthes
My son- 15-, is willing to create something with “chaux”, which locally is very cheap and mass produced nearby.
We would like to be in contact with somebody of your organisation, in order to have additionnal info,

thanks in advance

Lucy says: September 14th, 2017

Want more clients and customer from google

We can put your website on 1st page of Google to drive relevant traffic to your site. Let us know if you would be interested in getting detailed proposal. We can also schedule a call & will be pleased to explain our services in detail. We look forward to hearing from you soon. Thanks!

Alecia Reiter says: July 22nd, 2019


You Need Leads, Sales, Conversions, Traffic for ? Will Findet…


Don’t believe me? Since you’re reading this message then you’re living proof that contact form advertising works!
We can send your ad to people via their Website Contact Form.



Beaconher says: November 30th, 2021

then only a few have reached us

Leave a comment below