Ogresta Lovro, Nekvapil Fran, Tǎmaş Tudor, Barbu-Tudoran Lucian, Suciu Maria, Hirian Rǎzvan, Aluaş Mihaela, Lazar Geza, Levei Erika, Glamuzina Branko, Pinzaru Simona Cintǎ
Ioan Ursu Institute, Babeş-Bolyai University, 1 Kogǎlniceanu, Cluj-Napoca 400084, Romania.
Faculty of Science, University of Zagreb, Rooseveltov trg 6, Zagreb 10000, Croatia.
ACS Omega. 2021 Oct 11;6(42):27773-27780. doi: 10.1021/acsomega.1c03279. eCollection 2021 Oct 26.
Due to their chemical composition, richness in calcium carbonate, chitin, proteins, and pigments, and nanoporous structure, crustacean shell waste shows great potential for a wide variety of applications. Large quantities of waste shells are produced annually, meaning that they can be considered a renewable source of ecofriendly biogenic materials, which can be turned into value-added byproducts. In this paper, an IR-based technique is developed to differentiate various biogenic powders originated from crude or food-processed crustacean shells. The validity of the method is supported by cross-checking with XRD, NMR, and SEM-EDX analyses. Our goal was to determine changes in properties of waste crab shells after the two most common treatments, deproteinization and milling. We discovered that deproteinization with NaOH could be tracked from the IR absorbance intensity ratio of the υ(CH) and υ(CO ) bands while milling time less influenced this ratio but induced changes in powder particle size distribution and morphology. The relative organic/inorganic ratio was different for different colored shells. Unexpectedly, waste shells stored for an average of 6 months or more were found to contain hydrated calcium carbonate (monohydrocalcite), which was absent in equivalent fresh shell composition. Deproteinization caused changes in mechanical properties of shells, making them more brittle, which resulted in a larger fraction of fine particles after powdering.
由于其化学成分、富含碳酸钙、几丁质、蛋白质和色素以及纳米多孔结构，甲壳类动物的壳废料在各种应用中显示出巨大潜力。每年都会产生大量的废弃壳，这意味着它们可被视为一种可再生的生态友好型生物源材料，能够转化为增值副产品。本文开发了一种基于红外的技术，用于区分源自未加工或食品加工过的甲壳类动物壳的各种生物源粉末。通过与X射线衍射（XRD）、核磁共振（NMR）和扫描电子显微镜-能谱分析（SEM-EDX）交叉核对，证实了该方法的有效性。我们的目标是确定废弃蟹壳在两种最常见处理（脱蛋白和研磨）后的性质变化。我们发现，通过υ(CH)和υ(CO)带的红外吸收强度比可以追踪用氢氧化钠进行的脱蛋白过程，而研磨时间对该比例影响较小，但会导致粉末粒度分布和形态发生变化。不同颜色的壳的相对有机/无机比例不同。出乎意料的是，发现平均储存6个月或更长时间的废弃壳含有水合碳酸钙（一水方解石），而在同等新鲜壳成分中不存在这种物质。脱蛋白导致壳的机械性能发生变化，使其更脆，这导致粉末化后细颗粒的比例更大。
