Journal of Environmental Treatment Techniques
2020, Volume 8, Issue 3, Pages: 967-970
J. Environ. Treat. Tech.
Journal web link: http://www.jett.dormaj.com
Study of Eco-Processed Pozzolan Characterization as
Partial Replacement of Cement
Raihana Farahiyah Abd Rahman , Hidayati Asrah , Ahmad Nurfaidhi Rizalman , Abdul K.
Mirasa , M A A Rajak
Faculty of Engineering, Universiti Malaysia Sabah, 88400 Jalan UMS, Kota Kinabalu, Sabah, Malaysia
Preparatory Centre for Science & Technology, Universiti Malaysia Sabah, 88400 Jalan UMS, Kota Kinabalu, Sabah, Malaysia
Eco-processed pozzolan (EPP) is a sustainable product recycled from spent bleaching earth (SBE). It is recently used as a blended cement.
The pretreatment method of palm oil generates SBE as waste material in the refinery plant. Despite sending the SBE to the landfill, which
can lead to environmental pollution, it is extracted to produce sustainable products. The physical, chemical, mineralogical, and microstructural
characteristics of EPP were analysed. Furthermore, the conventional cement was substituted with 20% of EPP by cement mass in mortar.
The compressive strength of mortar containing EPP was determined for the assessment of strength activity index (SAI) of EPP. EPP consists
mainly of silica (SiO
2 2 2 3 2 3
), and the value of SiO , aluminium oxide (Al O ), and iron oxide (Fe O )combination was 68.98% which is more than
0%. According to the ASTM C618 standard, EPP could be categorised in the Class C pozzolan. The major crystalline phase of EPP was α-
quartz. Based on the micrograph image, EPP possesses some relatively spherical, irregular shaped, and agglomeration of its particles. At an
early curing age, the compressive strength of the mortar was increased with the inclusion of 20% of EPP. A high value of SAI can be reached
by mortar specimen with 20% of EPP.
Keywords: Eco-processed pozzolan, Pozzolan, Strength activity index
Palm oil fuel ash (POFA) , milled waste glass powder ,
clay brick powder , sugarcane bagasse ash , and fly ash 
have been investigated to be used to substitute conventional
cement in mortar and concrete. Because of its high percentage of
Crude palm oil refinery plant generates spent bleaching earth
(SBE) for approximately more than 2 million tonnes per year
globally . Malaysia is known to produce a huge number of
palm oil fruits. In the pretreatment process which is in the
degumming and bleaching of crude palm oil stage, bleaching
earth is added to produce refined palm oil. SBE is one of the
products of crude palm oil refining process. In Malaysia, the SBE
from a refinery plant is often sent to the landfills . The SBE
disposal at landfills can affect the greenhouse gas (GHG)
emission due to the natural anaerobic degradation. Recently,
EcoOils’ company provides a solution to recycle SBE to produce
sustainable products. Eco-processed pozzolan (EPP) is one of the
extracted products from SBE. The sustainable products extracted
from SBE are shown in Figure 1.
Recently, EPP has been used as blended cement. From the
previous studies, research on EPP as a pozzolanic material is
limited. Waste products with pozzolanic characteristics are
utilised in concrete to substitute cement, thus minimising the use
of cement . The use of pozzolanic material to replace cement
concrete . The reaction of SiO
), POFA has a high potential to substitute cement in
in pozzolanic material with the
calcium hydroxide produces more CSH gel. The CSH gel will
make the hardened paste denser and enhance its strength and
durability . In this study, the properties and the strength
activity index (SAI) of EPP were investigated. At 7 and 28 days
of curing, ordinary Portland cement was substituted with 20% of
EPP by cement mass in mortar to assess the SAI of EPP.
Materials and methods
In this study, the EPP was collected from EcoOils, Lahad
Datu. The EPP is as shown in Figure 2. The particle size of EPP
was measured by using laser diffraction particle size analyser.
The chemical oxides, mineralogical, and microstructural
characteristics of EPP were investigated by using X-ray
fluorescence (XRF), X-ray diffraction (XRD), and scanning
electron microscope (SEM), respectively. The ordinary Portland
cement was substituted with 20% of EPP by cement mass in
could minimise the release of carbon dioxide (CO ) from the
cement industry because the production of cement contributes to
%–7% of global CO emissions .
Corresponding author: Raihana Farahiyah Abd Rahman, Faculty of Engineering, Universiti Malaysia Sabah, 88400 Jalan UMS, Kota
Kinabalu, Sabah, Malaysia. Email: email@example.com.