Characterization of Oil Palm Empty Fruit Bunch and Rice Husk Biochars and Their Potential to Adsorb Arsenic and Cadmium

Abstract

Biochar as a new soil amendment has a potential in controlling the fate of trace elements in the soil system. However, the production of biochar from different feedstocks and pyrolysis conditions resulted in variable biochar properties which have an influence on trace elements availability. The experimental works are focused on physical and chemical properties of biochars produced from Empty Fruit Bunch (EFB) and Rice Husk (RH) as heavy metals adsorbents. The morphology of EFB biochar comprise rigid structure with uniform pores size. The surface area of biochars ranged between 23.22-46.32 m 2 g −1 , dominated with mesopores. The chemical characterization of biochars revealed high carbon content in EFB biochar compared to RH biochar (54.08 and 7.78%). Both biochars are alkaline in nature (>pH 9) and contain substantial amounts of N, P, K, Ca and Mg. Fourier transform infra-red spectra showed the heterogenic functional groups on EFB biochar surface and domination of silica content in RH biochar. The batch experiment was employed to determine the adsorption capacity of these biochars for As and Cd. The adsorption data were fitted well in Langmuir isotherm with high correlation coefficient (R 2 >0.9) for As and Cd. The q max of EFB biochar for As and Cd was higher than RH biochar. The q max of EFB biochar was 0.4240 and 15.1515 mg g −1 for As and Cd, respectively. In contrast, the q max of RH biochar for As and Cd was only 0.3522 and 3.1908 mg g −1 . The results show that EFB biochar and RH biochar have potentials as good sorbent for As and Cd. Therefore, it can be suggested that the application of these biochars may possibly reduce the trace elements availability in the contaminated soil.

The Physico-Chemical and Mineralogical Characterization of Mg-Rich Synthetic Gypsum Produced in a Rare Earth Refining Plant

“…The risk posed by heavy metals could be reduced with the co-application of organic amendments such as rice husk biochar (RH) and/or empty fruit bunch (EFB). Previous studies show that the sorption of such heavy metals (i.e., Cd, Cu, Zn, Fe, As) has the ability to bind to soil particles, hence reducing the bioavailability of the heavy metals in the soil solution [28][29][30][31]. For example, based on Langmuir's adsorption model, the maximum adsorption capacity (q max ) of EFB biochar for As was 0.42 mg g −1 , which was higher than RH biochar (0.35 mg g −1 ) [32].…”

Determining the characteristics and potential of plantbased biochars to reduce copper uptake in maize

“…The lowest pH was observed in RH1, with a reading of 7.87. Biochars from the pyrolysis processes were usually alkaline in nature with pH > 7.00 (Bagreev et al 2001;Sari et al 2014). Adding biochar into deionized water increases the solution pH and biochar produced at higher temperatures exhibit a higher pH.…”

Characterization of Empty Fruit Bunch Biochar Pyrolyzed at Different Temperatures with Respect to Activated Carbon and their Sorption Capacities for Pentachlorophenol

“…The high production rate of EFB makes it cheap and renewable feedstock for biochar production. Several studies have been reported on the application of empty fruit bunch biochar (EFBB) as a low cost adsorbent for the removal of contaminants from the environment [7][8][9][10]. The EFB is a lignocellulosic material which consists of 38.1-59.7 wt% cellulose, 16.8−22.1 wt% hemicellulose and 10.5−18.1 wt% lignin [11].…”