Production of bamboo leaf ash by auto-combustion for pozzolanic and sustainable use in cementitious matrices

Abstract

In the context of world concern with the environment, this study aims to characterize an auto-combustion produced bamboo leaf ash (BLA) by its pozzolanic behaviour, reactivity and its influence in the total porosity, pore size distribution, tortuosity and mechanical behaviour of cementitious matrices. The chemical and physical characterization of the BLA was carried using X-ray fluorescence, determination of amorphous silica content, X-ray diffraction, Fourier Transform Infrared Spectrophotometry (FTIR), laser granulometry and field emission scanning electron microscopy (FESEM). The assessed BLA is a siliceous material (74.23%) with an amorphous nature due to the amorphous silica content, which represents 92.33% of the total silica. The BLA was classified as highly reactive by assessing its pH and conductivity in a saturated calcium hydroxide (CH) medium for different proportions and temperatures. Frattini analysis, the study of CH:BLA pastes (Thermogravimetric analysis and FTIR) and Portland cement (OPC) /pozzolan pastes (Thermogravimetric analysis and FESEM) are in agreement with this classification. The replacement of OPC by BLA improved the mechanical behaviour of the cementitious matrices, as well their durability. All the mortars containing BLA presented very similar compressive strength to a control mortar (100% OPC) after only 3 days of curing and at the following tested curing ages: 7, 28 and 90 days. In the mercury intrusion porosimetry analysis, the pastes with 20 and 30% BLA content presented higher tortuosity or fewer connected pores than the control paste. Thus, the auto-combustion method proved to be successful and BLA is a suitable alternative for sustainable highperformance matrices.

Assessment and Evaluation of Blended Cement Using Bamboo Leaf Ash BLASH Against Corrosion

“…According to Dwivedi et al (2006), 20% bamboo leaf ash content has a compressive strength equivalent to that without ash [29]. Moreover, according to Moraes et al (2019), all mortars with bamboo leaf ash content have the same strength as ordinary Portland cement, even after 90 days of curing [35]. However, compared to this study, 20% bamboo leaf ash had a greater reduction in strength compared to the control specimen (0% BLASH).…”

“…The density of the fabricated composites decreased with the addition of bamboo leaf ash particles, and the hardness and tensile strength improved significantly [34]. Moraes et al (2019) characterized bamboo leaf ash production with auto-combustion based on its pozzolanic behavior. Bamboo leaf ash admixtures are classified as highly conductive and have high pH values [35].…”

“…Moraes et al (2019) characterized bamboo leaf ash production with auto-combustion based on its pozzolanic behavior. Bamboo leaf ash admixtures are classified as highly conductive and have high pH values [35]. Onikeku et al (2019) also examined the use of bamboo leaf ash as a supplementary cementitious material.…”

Bamboo ashes as an eco-friendly alternative to cement - a systematic review

“…Bamboo ashes are produced by calcining the plant culm (ABOLUWARIN et al, 2017;RODIER et al, 2017;DAVID;HASSAN, 2018;MUJEDU et al, 2018;IKEAGWUANI et al, 2019) or its leaves (DWIVEDI et al, 2006;FRÍAS et al, 2012 MORAES et al, 2019;ONIKEKU et al, 2019;RODIER et al, 2019) (Figure 1). The preference for producing ashes from bamboo leaves can be associated with the high amount of silica (SiO2) accumulated in the leaves along the plant life cycle (MOTOMURA;…”

Cenizas De Biomasa: Una Oportunidad Para Incrementar Los Beneficios Medioambientales Y Tecnológicos De Hormigones Con Cemento Portland Y Geopoliméricos

“…Por último, trazas de otros elementos (Mg, P, S) completan la composición química de la CHB. El uso de la CHB como material suplementario cementante para la sustitución de cemento Portland en morteros implica la posibilidad de contribución puzolánica debido a la presencia de sílice amorfa (Moraes et al, 2019). Así, por ejemplo, en morteros normalizados con sustitución de 25% por CHB, se obtienen una resistencia mecánica a 28 días que supone el 115% del motero control.…”