Scholarlink

<p>Qatar produces approximately 2 million tons of agricultural biomass waste annually. Less than 20% is currently recycled or valorized, mainly through limited composting, landfilling, and, in some cases, open burning. This study presents a systematic production and multi-scale characterization of biochar derived from local mixed green agricultural waste (GAGW) and woody agricultural waste (WAGW), providing a characterization-based foundation to inform their potential integration into the energy-water-food (EWF) nexus of arid regions. Each feedstock was analyzed for moisture content (MC), volatile matter (VM), ash content, fixed carbon (FC), elemental composition (C, H, N, S), molar ratios (H/C, O/C), structural, elemental, morphological, thermal combustion and specific surface area properties. The experimental design follows a double-split arrangement. GAGW and WAGW were considered as the main plots, pyrolysis temperature (300, 400, 500, and 600&#xa0;°C) as the sub-main plots, and residence time (20, 60, 90, and 120&#xa0;min) as the sub-sub plots. Results demonstrate a fundamental divergence in carbonization pathways. WAGW achieved a peak solid yield of 71.28% at 300&#xa0;°C in 20&#xa0;min, significantly outperforming GAGW (60%). As thermal severity increased to 600&#xa0;°C, WAGW underwent superior structural development, reaching a specific surface area of 684 m<sup>2</sup>/g, about 3 times higher than GAGW. Van Krevelen analysis validated the transition to highly recalcitrant aromatic frameworks, with WAGW reaching a superior H/C ratio of 0.30 compared to 0.35 for GAGW. While WAGW produced a carbon-dense matrix (82.6 atom% C), GAGW evolved into a nutrient-active medium, concentrating potassium (88,780&#xa0;mg/kg) and calcium (63,932&#xa0;mg/kg) in stable sylvite and calcite phases, as affirmed via X-ray Diffraction (XRD). Crucially, all produced biochar samples were free from hazardous heavy metals (As, Cd, Cr, Pb, Hg &lt; 0.1&#xa0;mg/kg), confirming their safety profile and suitability for further evaluation in potential soil and water applications.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Productivity evaluation, multi-scale characterisation, and safety assessment of biochar derived from green and woody agricultural biomass in Qatar

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年5月25日

查看全文
  • Rashad Al-Gaashani,
  • Omar Shahid,
  • Ojima Z. Wada,
  • Simjo Simson,
  • Tricia A. Gomez,
  • Mujaheed Pasha,
  • Omar El Hassan,
  • Abdulaziz Suwailem,
  • Kashif Rasool,
  • Gordon McKay,
  • Tareq Al-Ansari,
  • Khaled A. Mahmoud

摘要

Qatar produces approximately 2 million tons of agricultural biomass waste annually. Less than 20% is currently recycled or valorized, mainly through limited composting, landfilling, and, in some cases, open burning. This study presents a systematic production and multi-scale characterization of biochar derived from local mixed green agricultural waste (GAGW) and woody agricultural waste (WAGW), providing a characterization-based foundation to inform their potential integration into the energy-water-food (EWF) nexus of arid regions. Each feedstock was analyzed for moisture content (MC), volatile matter (VM), ash content, fixed carbon (FC), elemental composition (C, H, N, S), molar ratios (H/C, O/C), structural, elemental, morphological, thermal combustion and specific surface area properties. The experimental design follows a double-split arrangement. GAGW and WAGW were considered as the main plots, pyrolysis temperature (300, 400, 500, and 600 °C) as the sub-main plots, and residence time (20, 60, 90, and 120 min) as the sub-sub plots. Results demonstrate a fundamental divergence in carbonization pathways. WAGW achieved a peak solid yield of 71.28% at 300 °C in 20 min, significantly outperforming GAGW (60%). As thermal severity increased to 600 °C, WAGW underwent superior structural development, reaching a specific surface area of 684 m2/g, about 3 times higher than GAGW. Van Krevelen analysis validated the transition to highly recalcitrant aromatic frameworks, with WAGW reaching a superior H/C ratio of 0.30 compared to 0.35 for GAGW. While WAGW produced a carbon-dense matrix (82.6 atom% C), GAGW evolved into a nutrient-active medium, concentrating potassium (88,780 mg/kg) and calcium (63,932 mg/kg) in stable sylvite and calcite phases, as affirmed via X-ray Diffraction (XRD). Crucially, all produced biochar samples were free from hazardous heavy metals (As, Cd, Cr, Pb, Hg < 0.1 mg/kg), confirming their safety profile and suitability for further evaluation in potential soil and water applications.