植物单宁是环境友好的鞣剂。然而,它们通常赋予鞣制的皮革深色,并高度增加废水中的有机负荷。在这项研究中,我们分别对栗子单宁(CT)和硫酸化砂单宁(QT)采用纯化方案,以获得纯化的馏分(PCT和PQT)。这些样品通过GPC表征,1HNMR,13CNMR,FT-IR,和HPLC-DAD技术,并应用于鞣制试验。经由过程净化,非单宁成分和较小的分子如没食子酸,吡喃葡萄糖,从CT和QT中有效去除儿茶素,从而导致水分含量降低,pH值,和较浅的颜色纯化的馏分。用PCT和PQT处理的外壳皮革显示出理想的浅色阴影。此外,PCT和PQT制革废水中的有机负荷分别降低了13.5%和19.1%,分别,与传统CT和QT制革废水相比。此外,PCT和PQT处理的外壳皮革的物理和机械特性与CT和QT处理的外壳皮革相当。因此,植物单宁的纯化可以作为生产浅色植物鞣制皮革的可行策略,同时在植物鞣制过程中最大程度地减少有机污染物的排放。
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■在线版本包含补充材料,可在10.1186/s42825-024-00171-9获得。
Vegetable tannins are environmentally friendly tanning agents. However, they generally impart a dark colour to the tanned leather and highly contribute to the organic load in wastewaters. In this study, we employed a
purification protocol separately on chestnut tannin (CT) and sulfited quebracho tannin (QT) to obtain the purified fractions (PCT and PQT). These samples were characterised by GPC, 1H NMR, 13C NMR, FT-IR, and HPLC-DAD techniques and applied for tanning tests. Through the
purification process, non-tannin components and smaller molecules such as gallic acid, glucopyranose, and catechin were effectively removed from CT and QT, which consequently led to the reduced moisture content, pH value, and lighter colour of purified fractions. The crust leathers processed with PCT and PQT showed desirable light shades. Moreover, the organic loads in PCT and PQT tanning wastewater were reduced by 13.5% and 19.1%, respectively, when compared to those in traditional CT and QT tanning wastewater. Additionally, the physical and mechanical characteristics of crust leathers processed with PCT and PQT were comparable to those processed with CT and QT. Thus,
purification of vegetable tannins may serve as a feasible strategy for producing light-colored vegetable-tanned leather while minimizing organic pollutant discharge during the vegetable tanning process.
UNASSIGNED: UNASSIGNED: The online version contains supplementary material available at 10.1186/s42825-024-00171-9.