Auteri Nicolò, Scalenghe Riccardo, Saiano Filippo
Dipartimento Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Italy.
Heliyon. 2023 Sep 12;9(9):e19996. doi: 10.1016/j.heliyon.2023.e19996. eCollection 2023 Sep.
In this study, the potential of cactus pear pruning waste (CPPW) as a low-cost adsorbent biomass for phosphorus (P) removal from aqueous solutions was investigated in batch mode. Biomass samples derived from cactus pear were collected and analyzed to investigate their properties when enriched with either calcium (Ca) or iron (Fe). The examination focused on the capacity of these samples to remove P. The P removal capacities were determined to be 2.27 mg g, 1.33 mg g, and 1.87 mg g for Ca-enriched, Fe-loaded, and Fe-loaded biomass respectively. Among the various models studied, the Langmuir isotherm model was identified as the most appropriate for accurately describing the P adsorption the enriched biomass. The kinetics of the adsorption process were analyzed by applying the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The pseudo-second-order model provided the best fit to the experimental data. Furthermore, the desorption and regeneration process was investigated, revealing minimal P desorption (less than 8%) from Ca or Fe-loaded biomass, indicating the strong stability of the biomass-cation-P system. The estimated cost ranged from 8 to 161 euros per tonne, with an additional 230 euros when considering the pruning costs inherent to the crop. These costs fall below the threshold (320 euros per tonne) for the economically viable P reuse at the farm level. Consequently, CPPW, when reduced to powder and loaded with ions, emerges as an affordable adsorbent with good removal performance, offering a promising avenue for direct utilization in agriculture as both soil conditioner and fertiliser.
在本研究中，以批次模式研究了仙人掌修剪废弃物（CPPW）作为一种低成本吸附生物质从水溶液中去除磷（P）的潜力。收集并分析了源自仙人掌的生物质样品，以研究其在富含钙（Ca）或铁（Fe）时的特性。研究重点是这些样品去除P的能力。测定富含Ca、负载Fe和负载Fe的生物质的P去除能力分别为2.27 mg/g、1.33 mg/g和1.87 mg/g。在所研究的各种模型中，朗缪尔等温线模型被确定为最适合准确描述富含生物质对P的吸附。通过应用拟一级、拟二级和颗粒内扩散模型分析吸附过程的动力学。拟二级模型与实验数据拟合最佳。此外，还研究了解吸和再生过程，结果表明，Ca或Fe负载生物质的P解吸量极小（小于8%），表明生物质-阳离子-P系统具有很强的稳定性。估计成本为每吨8至161欧元，若考虑作物固有的修剪成本，则额外增加230欧元。这些成本低于农场层面经济可行的P再利用阈值（每吨320欧元）。因此，CPPW磨成粉末并负载离子后，成为一种价格合理且去除性能良好的吸附剂，为在农业中直接用作土壤改良剂和肥料提供了一条有前景的途径。
