Sustainable Waste Valorization: Chitosan From Shrimp Shells For Eco-friendly Cement Mortars And Global Nexus

Authors

• Dalia A. Ali Associate Prof., The British University in EgyptFollow
• Rahma H. Thabet Dr., Menoufia University
• Norah Alwadai Associate Prof., Princess bint Abdulrahman University
• Fekri Abdulraqeb Ahmed Ali Prof., Imam Mohammad Ibn Saud Islamic University (IMSIU)
• Ahmed S. Al-Fatesh Prof., King Saud University
• Zeinab A. Etman Prof., Menoufia University

Document Type

Article

Publication Date

Summer 6-7-2026

Abstract

This study addresses environmental and economic challenges by investigating the valorization of green shrimp shell biowaste into chitosan for application as an eco-friendly, sustainable, and multifunctional cement mortar additive. Chitosan synthesized from shrimp shells was systematically incorporated into high early-strength hydraulic cement mortar specimens ranging from 0 wt% to 1.5 wt% in the presence of silica sand. The influence of chitosan incorporation on the properties of cement mortars was systematically investigated, including mechanical performance (compressive strength and setting time), the underlying mechanism of chemical interactions, and microstructural development. X-ray diffraction (XRD) analysis was performed on the extracted chitosan to confirm its semi-crystalline nature. Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA) were conducted on cement mortar samples containing 0 wt% to 1.5 wt% to investigate chemical interactions and thermal behavior. Scanning electron microscopy (SEM) was used to examine the microstructural evolution of a cement paste sample with 1 wt% chitosan at curing ages of 2, 7, and 28 days. The novelty of this study lies in the incorporation of a comparative, cradle-to-gate preliminary Life Cycle Assessment (LCA) to evaluate the environmental impact of shrimp shell-derived chitosan production relative to that of a traditional polycarboxylate ether (PCE) superplasticizer. The results showed that chitosan significantly influences cement hydration by enhancing particle dispersion within the mortar matrix, resulting in a considerable improvement in early-age compressive strength. Notably, the 1 wt% chitosan mixture achieved a compressive strength of 29.81 MPa in 2 days representing an increase of more than 200% compared to the control sample. The cradle-to-gate LCA (Functional Unit: 1 kg) revealed that PCE production has a ∼ 40% higher global warming potential and ∼ 25% higher fossil resource scarcity than chitosan. Conversely, chitosan production exhibited higher freshwater eutrophication (contributed ∼ 75% by chemical processing) and human toxicity. Chitosan demonstrated a net environmental credit in water consumption due to the avoided burden of shell waste disposal.

Recommended Citation

Rahma H. Thabet, Dalia A. Ali, Norah Alwadai, Fekri Abdulraqeb Ahmed Ali, Ahmed S. Al-Fatesh, Zeinab A. Etman, Sustainable waste valorization: chitosan from shrimp shells for eco-friendly cement mortars and global Nexus, Chemical Engineering Science, Volume 335, 2026, 124373, ISSN 0009-2509, https://doi.org/10.1016/j.ces.2026.124373. (https://www.sciencedirect.com/science/article/pii/S0009250926010882) Abstract: This study addresses environmental and economic challenges by investigating the valorization of green shrimp shell biowaste into chitosan for application as an eco-friendly, sustainable, and multifunctional cement mortar additive. Chitosan synthesized from shrimp shells was systematically incorporated into high early-strength hydraulic cement mortar specimens ranging from 0 wt% to 1.5 wt% in the presence of silica sand. The influence of chitosan incorporation on the properties of cement mortars was systematically investigated, including mechanical performance (compressive strength and setting time), the underlying mechanism of chemical interactions, and microstructural development. X-ray diffraction (XRD) analysis was performed on the extracted chitosan to confirm its semi-crystalline nature. Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA) were conducted on cement mortar samples containing 0 wt% to 1.5 wt% to investigate chemical interactions and thermal behavior. Scanning electron microscopy (SEM) was used to examine the microstructural evolution of a cement paste sample with 1 wt% chitosan at curing ages of 2, 7, and 28 days. The novelty of this study lies in the incorporation of a comparative, cradle-to-gate preliminary Life Cycle Assessment (LCA) to evaluate the environmental impact of shrimp shell-derived chitosan production relative to that of a traditional polycarboxylate ether (PCE) superplasticizer. The results showed that chitosan significantly influences cement hydration by enhancing particle dispersion within the mortar matrix, resulting in a considerable improvement in early-age compressive strength. Notably, the 1 wt% chitosan mixture achieved a compressive strength of 29.81 MPa in 2 days representing an increase of more than 200% compared to the control sample. The cradle-to-gate LCA (Functional Unit: 1 kg) revealed that PCE production has a ∼ 40% higher global warming potential and ∼ 25% higher fossil resource scarcity than chitosan. Conversely, chitosan production exhibited higher freshwater eutrophication (contributed ∼ 75% by chemical processing) and human toxicity. Chitosan demonstrated a net environmental credit in water consumption due to the avoided burden of shell waste disposal. Keywords: Chitosan; Cement mortar; Life Cycle Assessment (LCA); Waste valorization; Environmental engineering