Pistachio Shell Ash in Agro-Waste Cement Composites: A Pathway to Low-Carbon Binders

Mahmut Durmaz () and Murat Doğruyol
Additional contact information
Mahmut Durmaz: Department of Civil Engineering, Faculty of Engineering, Siirt University, Siirt 56000, Türkiye
Murat Doğruyol: Department of Civil Engineering, Faculty of Engineering, Siirt University, Siirt 56000, Türkiye

Sustainability, 2025, vol. 17, issue 9, 1-16

Abstract: This study evaluates pistachio shell ash (PSA) as a sustainable cement substitute and investigates its effect on setting time, strength and microstructure. In this study, pistachio shell ash (PSA) obtained from the kiln flue gas filter of pistachio shells burnt at 300–350 °C in an industrial kiln was used. PSA was substituted for ordinary Portland cement (OPC) at 5, 10, 15, 20, 25 and 30%. PSA increased the SO 3 value in the cement mortars, so 5% PSA substitution delayed the cement setting time by up to 174%. However, it increased the water requirement of the cement mortar by about 2%. While it increased the early strength (22% on day 1, 15% on day 2, and 5% on day 7), the 28-day strength decreased slightly (about 4.5%) due to low pozzolanic activity. Microstructural analyses such as SEM-EDX and XRD showed that the calcite and gypsum phases of PSA provided early strength gains, but there were long-term losses. With a 5% replacement rate, PSA provides significant environmental benefits by reducing CO 2 emissions while maintaining optimum mechanical performance and supports the circular economy through the efficient use of agricultural waste.

Keywords: pistachio shell ash; setting time; compressive strength; biomass; cement (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/17/9/4003/pdf (application/pdf)
https://www.mdpi.com/2071-1050/17/9/4003/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:17:y:2025:i:9:p:4003-:d:1645618

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().