In this work, rice husks (RH) from 4 agro-ecological zones of Tanzania were characterised for their potential use via supercritical water gasification (SCWG). The physical and chemical characteristics of different varieties of RH were evaluated, and the results were correlated with their geographical factors. The SCWG was conducted at a temperature of 492 °C, feed concentration of 9.5 wt%, residence time of 120 min, and catalyst loading of 15%. The catalyst was prepared by impregnating calcined limestone with 5% iron from the iron (III) ammonium citrate precursor. The RH samples exhibit a moisture content of 6.3–6.9 wt%, volatile matter 56.8–62.8% dry basis (%db), fixed carbon 11.64–19.5%db, ash content 22.2–27.3%db, and carbon content 29.97–3.4%db. The higher heating value ranged between 12.0 and 12.8 MJkg⁻¹, extractives from 10.93 to 18.0%db, cellulose from 34.4 to 38.5%db, lignin from 16.3 to 17.5%db, and hemicellulose from 17.0 to 21.0%db. The results from noncatalytic SCWG showed that the gasification efficiency (GE) varied between 59.3 and 62.7%, gas volume between 278.5 and 305.2 mLg⁻¹ biomass, gravimetric tar between 24.3 and 31.6 mgg⁻¹ biomass, and char yield between 34.6 and 38.6 wt%. Phase characterisation of the fabricated catalyst showed that the main reactive sites are Ca₂Fe₂O₅, CaO and Fe₂O_3, which promote char gasification and gas and tar formation reactions. When 5%Fe/limestone is employed, the GE ranges between 69.3 and 73.6%, gas volume is between 401.8 and 427.3 mLg⁻¹, tar yield ranges between 57.5 and 62.8 mgg⁻¹, and char between 20.1 and 24.9 wt%. The findings show that the fabricated catalyst is suitable for the simultaneous production of gaseous and liquid biofuels from rice husks via the SCWG process.

在这项工作中，来自坦桑尼亚 4 个农业生态区的稻壳 (RH) 通过超临界水气化 (SCWG) 对其潜在用途进行了表征。评价了不同品种RH的理化特性，并将结果与​​其地理因素相关联。SCWG 在 492 °C 的温度、9.5 wt% 的进料浓度、120 分钟的停留时间和 15% 的催化剂负载下进行。该催化剂是通过用来自柠檬酸铁 (III) 铵前体的 5% 铁浸渍煅烧石灰石制备的。RH 样品的水分含量为 6.3–6.9 wt%，挥发物为 56.8–62.8% 干基 (%db)，固定碳为 11.64–19.5%db，灰分含量为 22.2–27.3%db，碳含量为 29.97–3.4% D b。较高的热值介于 12.0 和 12.8 MJkg ^−1之间，提取物从 10.93 到 18.0%db，纤维素从 34.4 到 38.5%db，木质素从 16.3 到 17.5%db，半纤维素从 17.0 到 21.0%db。非催化 SCWG 的结果表明，气化效率 (GE) 在 59.3 和 62.7% 之间变化，气体体积在 278.5 和 305.2 mLg ^-1生物质之间，重量焦油在 24.3 和 31.6 mgg ^-1生物质之间，焦油产量在 34.6 和 38.6 wt 之间。 %。制备的催化剂的相表征表明，主要的反应位点是 Ca ₂ Fe ₂ O ₅、CaO 和 Fe ₂ O _{3 ，}促进焦炭气化以及气体和焦油形成反应。当使用 5%Fe/石灰石时，GE 在 69.3 和 73.6% 之间，气体体积在 401.8 和 427.3 mLg ^-1之间，焦油产率在 57.5 和 62.8 mgg ^-1之间，焦油在 20.1 和 24.9 wt% 之间。研究结果表明，制造的催化剂适用于通过 SCWG 工艺从稻壳中同时生产气态和液态生物燃料。