Bin Mobarak Mashrafi, Pinky Nigar Sultana, Mustafi Sonjida, Chowdhury Fariha, Nahar Aynun, Akhtar Umme Sarmeen, Quddus Md Saiful, Yasmin Sabina, Alam Md Ashraful
Institute of Glass and Ceramic Research and Testing (IGCRT), Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka-1205 Bangladesh
Biomedical and Toxicological Research Institute (BTRI), Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka-1205 Bangladesh.
RSC Adv. 2024 Sep 19;14(41):29848-29859. doi: 10.1039/d4ra05562d. eCollection 2024 Sep 18.
Utilization of agricultural waste to produce biochar has already proven to be an efficient method for transforming waste into valuable resources. In this study, rubber seed shell (RSS) was utilized to prepare two biochar samples an in-house built reactor (RSSBC-1) and a pyrolysis reactor (RSSBC-2) under identical conditions (600 °C for 3 h at a heating rate of 10 °C per min). A comprehensive characterization of the prepared biochar samples was carried out to reveal the reactor effect on the biochar properties. For this, proximate and ultimate analyses were carried out which estimated the carbon stability, polarity, and aromaticity of the biochar samples. For RSSBC-1, C and N content were higher, whereas H and O content were higher for RSSBC-2, as found from elemental, EDX, and XPS analyses. Point of zero charge (PZC) values of 7.65 and 6.14 for RSSBC-1 and RSSBC-2, respectively, emphasized the importance of pH in the removal of ionic contaminants. Furthermore, the superiority of RSSBC-1 in terms of specific surface area of 336.02 m g compared to 299.09 m g of RSSBC-2 was articulated by BET analysis. XPS and FESEM analyses revealed the chemical state of surface elements and surface morphology, respectively of the biochar samples. XRD patterns assured the amorphous nature of biochar samples, and functional groups were well depicted by FTIR analysis. DLS showed a larger average hydrodynamic diameter for RSSBC-2 (248.68 nm) with a zeta potential of -14.91 mV compared to RSSBC-1 (115.23 nm) with a heterogeneous charge distribution (-16.72 mV and +37.61 mV). TGA analysis revealed the thermal stability of both biochar samples. Overall, the results explicitly depict a distinction in the properties of biochar samples prepared in two different reactors, where RSSBC-1, with its superior properties suggests the in-house built reactor as a promising alternative to expensive pyrolytic reactors for waste valorization.
利用农业废弃物生产生物炭已被证明是一种将废弃物转化为有价值资源的有效方法。在本研究中，橡胶籽壳（RSS）被用于在相同条件下（600℃，以每分钟10℃的加热速率加热3小时）制备两种生物炭样品——一个自制反应器制备的（RSSBC - 1）和一个热解反应器制备的（RSSBC - 2）。对制备的生物炭样品进行了全面表征，以揭示反应器对生物炭性质的影响。为此，进行了近似分析和元素分析，以评估生物炭样品的碳稳定性、极性和芳香性。通过元素分析、能谱分析（EDX）和X射线光电子能谱分析（XPS）发现，对于RSSBC - 1，碳（C）和氮（N）含量较高，而对于RSSBC - 2，氢（H）和氧（O）含量较高。RSSBC - 1和RSSBC - 2的零电荷点（PZC）值分别为7.65和6.14，这突出了pH值在去除离子污染物方面的重要性。此外，通过比表面积分析（BET）表明，RSSBC - 1的比表面积为336.02 m²/g，优于RSSBC - 2的299.09 m²/g。XPS和场发射扫描电子显微镜分析（FESEM）分别揭示了生物炭样品表面元素的化学状态和表面形态。X射线衍射图谱（XRD）证实了生物炭样品的无定形性质，傅里叶变换红外光谱分析（FTIR）很好地描绘了官能团。动态光散射（DLS）显示，与具有异质电荷分布（-16.72 mV和+37.61 mV）的RSSBC - 1（115.23 nm）相比，RSSBC - 2的平均流体动力学直径更大（248.68 nm），zeta电位为-14.91 mV。热重分析（TGA）揭示了两种生物炭样品的热稳定性。总体而言，结果明确显示了在两种不同反应器中制备的生物炭样品在性质上的差异，其中具有优异性能的RSSBC - 1表明自制反应器是一种有前途的替代昂贵热解反应器用于废弃物增值利用的选择。
