Date Palm (Phoenix Dactylifera L.) Seed Characterization for Biochar Preparation

Abstract

Biochar has been increasingly used as a soil amendment, clean energy source and waste\nmanagement tool. It is also promoted as a climate change mitigation tool through carbon\nsequestration in soil. Recently, there is an increasing interest in biochar utilization as a low\ncost adsorbent for organic and non-organic pollutant removal. Biochar can be prepared from\na wide range of organic biomass. Date seed biomass (Phoenix dactylifera L.) is abundantly\navailable but usually discarded as agricultural waste in many countries such as Iraq. The aim\nof this work was to evaluate date seed characteristics by using proximate and ultimate\nelementary analyses for biochar preparation. Results of this study showed that date seed\nbiomass had high volatile content, high bulk density and low ash content suggesting that the\nbiomass can be used as a suitable precursor for biochar preparation. The results revealed that\nthe moisture content of biomass was 8.95% with a bulk density of 0.5 g/ml. The proximate\nanalysis indicated that the biomass had 1.14% ash content, 65% volatile matter and 24.8%\nfixed carbon content on a dry–weight basis. The date seed biomass showed an acidity nature\nof pH of 4.8. The ultimate elementary analysis indicated that the biomass had a carbon\ncontent of 28.3% and nitrogen content of 0.7%. The effects of pyrolysis temperature on mass\nyield, porosity and pH of the biochar were also studied. The biochar was prepared by using\na slow pyrolysis process under different temperatures (350, 450, 550 and 650 oC) for 2 h.\nThe results of the analysis indicated that the biochar properties were strongly affected by the\npyrolysis temperature. The biochar mass yield was inversely proportional to the pyrolysis\ntemperature. The mass yields were 43.3%, 33%, 27% and 22% at temperatures (350, 450,\n550 and 650 oC), respectively. The pH and porosity of the biochar increased with the\npyrolysis temperature. Therefore, the biochar prepared from date seed had a highly porous\nstructure and thus it is expected to a suitable adsorbent for heavy metal ion removal in\nwastewater systems.