Bachelor's Thesis

The use of biochar as supplementary cementitious material for production of eco-friendly mortars

Final Thesis 1.46 MB

Author of thesis: Bc. Matěj Macháček

Acad. year: 2025/2026

Supervisor: doc. Ing. Nikol Žižková, Ph.D.

Reviewer: Ing. Lubomír Sokola, Ph.D.

Abstract:

This bachelor's thesis deals with the use of biochar as an innovative cement substitute for the production of eco-friendly mortars with a reduced carbon footprint.
Biochar, a fine-grained carbonaceous product obtained by pyrolysis of biomass, functions as an effective storage of stable carbon, which is safely fixed in the cement matrix for tens to hundreds of years.
The main objective of the thesis is the development and assessment of the real potential of eco-friendly mortars, where cement is replaced by a percentage of biochar by weight. The key physical properties of three selected types of biochar were determined and their suitability for the production of mortars or cement composites was verified. Furthermore, physical-mechanical tests of the mortars were performed, monitoring their behavior in the fresh state and subsequently the strength characteristics of the hardened mortar. A microstructure study was performed for selected mortars.
The outputs of the thesis provide a comprehensive assessment of the influence of biochar on the properties of the produced mortars.

Keywords:

construction industry; biochar; biomass; pyrolysis; mortar; cementitious composite

Date of defence

15.06.2026

Result of the defence

Defended (thesis was successfully defended)

znamkaAznamka

Grading

A

Process of defence

Student představil komisi formou prezentace svoji bakalářskou práci a reagoval na připomínky a dotazy od oponenta vyjádřené v oponentském posudku i na otázky členů komise. Během obhajoby položili členové komise následující otázky: Ing. Aleš Jakubík, Ph.D. – Zkoumal jste jak je výroba biocharu ekonomicky náročná? Ing. Pavla Matulová, Ph.D. – Kde jste přišel na tento materiál, jak vás napadlo ho použít? prof. Ing. Rostislav Drochytka, CSc., MBA, dr.h.c. – Sledoval jste chemické složení biocharu? Má to vliv na jeho použití? prof. Ing. Jiří Zach, Ph.D. – Proč máte měrný povrch v cm2/g? Nejsou ty hodnoty nízské k měrné hmotnosti a nasákavosti? Student výborně reagoval a zaujímal svoje stanovisko ke všem připomínkám k předložené BP od oponenta i členů komise.

Language of thesis

Czech

Faculty

Fakulta stavební

Department

Institute of Technology of Building Materials and Components

Study programme

Civil Engineering (BPC-SI)

Specialization

Building Materials and Technologies (M)

Composition of Committee

Ing. Aleš Jakubík, Ph.D. (předseda)
Ing. Pavla Matulová, Ph.D. (místopředseda)
prof. Ing. Rostislav Drochytka, CSc., MBA, dr. h. c. (člen)
prof. Ing. Rudolf Hela, CSc. (člen)
prof. Ing. Jiří Zach, Ph.D. (člen)
prof. Ing. Karel Dvořák, Ph.D. (člen)
doc. Ing. Radomír Sokolář, Ph.D. (člen)

Supervisor’s report
doc. Ing. Nikol Žižková, Ph.D.

Grade proposed by supervisor: A

File inserted by supervisor Size
Hodnoceni_vedouciho_M. Macháček [.pdf] 117,90 kB

Reviewer’s report
Ing. Lubomír Sokola, Ph.D.

Grade proposed by reviewer: A

File inserted by the reviewer Size
Posudek oponenta [.pdf] 124,40 kB

Responsibility: Mgr. et Mgr. Hana Odstrčilová