Dear Hasan Altawil ,

I checked the article and I have appreciated you have done lot of practical testing, using very skilled way to work.

But there is a problem, technically speaking, there is no Geopolymer content inside the materials you developed.

Geopolymerization is polymeric process not hydraulic like the one you have so precisely described. You wrote about dissolution of Fly ash C, used as precursor, using from strong alkaline media to more diluted. Yo have understood that water is a key parameter, but maybe not for the right reasons. Using more alkaline medium you have obtained higher results than using lower pH and even here is understandable, but again, the reaction is not so linear as you wrote, because it isn’t the final step of precipitation and drying at room temperature or using heating.

Geopolymerization isn’t a dissolving/precipitation and condensation system, like AlkalI Activated Materials instead are. Precursor is selected because its reactivity or because it’s easy to be depolymerized (in both alkaline or acidic environments). So Fly ash C isn’t good precursor, properly because, following your words, it’s so rich in CaO that can be dissolved by alkaline pH generating precipitation of Ca(OH)2 so hydrate Lime. That lime reacted with the silica fume that you used to densificate your mortar and at the same time it’s pozzolanic. The high or less pH used (NaOH from 10 to 16 Molar) just accelerate and help that pozzolanic reaction enhancing the mechanical strength. Definitely very good work, obtaining more than 20 MPa of pozzolanic mortar. At the same time, all the minerals resulted from this reaction are hydraulic, but not polymers at all.

Geopolymer precursor is so reactive that doesn’t need to be activated by anything. For this reason the liquid part of every Geopolymer binders is technically called reagent or hardener and it’s pH must be precise depending on the application you want to do.

Check at the site www.geopolymer.org and I hope you can be supported by your university (students have discount) to participate at the next GP Camp from 7th to 9th of July 2025. The workshop, the first day , would be the most important for you as student and future worker. You could also check at the book of Professor Davidovits that explains the fundamentals of Geopolymerization with focus on real industrial applications from more than 40 years.

We could meet physically there, every year from 2016 I attend presenting new Geopolymer materials for industrial uses.

Only understanding what mineral polymerization (aka Geopolymerization) is and what is not, your work could become precious for the University‘s community.

With my best regards

Dr. Alex Reggiani

CTO GeoMITS

Dear Hasan Altawil ,

Congratulations on your publication! Your research on optimizing geopolymer mortar properties using the Taguchi method is very interesting and relevant to sustainable construction. I would love to read your full article—would it be possible for you to share a copy?

Looking forward to your response and further discussions on this topic.

Best regards,