富含碱金属和非结构成分的生物残留物(马铃薯茎)经过热水(353 K)或酸性(0.1 mol/L 盐酸)水清洗。酸性预处理对脱矿质更有效,碱含量减少了 99%(粉末)或 90%(颗粒),相当于有机物溶解量分别约为 35% 或 17%(重量)。热水洗涤的后者数字大致相同(38 和 19 wt%),但碱仅减少了 78 或 64%。热重分析和 SEM-EDX 分析表明,渗滤液特性很大程度上取决于溶剂类型和残留物粒度。洗涤后的生物残留物在一定温度下分解,并且随着预处理变得更加严格(细粒度和酸性水洗涤),分解速度逐渐增加。先前针对未经处理的材料开发的多步骤全局动力学,并经过适当重新审视以纳入洗涤效果,揭示了重要成分变化的趋势。尽管淀粉溶解,但绝对峰值速率区的挥发性产物产量增加了约 40-65%,证明了纤维素含量的增加。果胶化合物几乎被消除,有利于肩部速率区,代表半纤维素分解,挥发性产物产量增加约 22-78%。
"点击查看英文标题和摘要"
Devolatilization characteristics of a bio-residue (potato stems) with high contents of alkali metals and non-structural components – Influences of the washing pretreatment severity
A bio-residue (potato stems), rich in alkali metals and non-structural components, is subjected to hot (353 K) or acidic (0.1 mol/L hydrochloric acid) water washing. The acidic pretreatment is more effective for the demineralization, with alkalis reduced by 99 (powders) or 90 (particles) %, corresponding to organic matter dissolution around 35 or 17 wt%, respectively. The latter figures remain approximately the same for hot water washing (38 and 19 wt%) but alkalis are reduced only by 78 or 64 %. The leachate properties are significantly dependent on the solvent type and the residue granulometry, as indicated by thermogravimetric and SEM-EDX analysis. Washed bio-residues decompose at temperatures and with rates progressively increasing as the pretreatment becomes more severe (fine granulometry and acidic water washing). Multi-step global kinetics, previously developed for the untreated material and properly revisited to incorporate washing effects, reveals trends with important compositional changes. Despite starch dissolution, volatile product yields for the absolute peak rate zone increase by about 40–65 %, testifying augmented cellulose contents. The pectin compounds are almost eliminated, to the advantage of the shoulder rate zone, representing hemicellulose decomposition, with an increase in the volatile product yields around 22–78 %.