Department of Applied Chemistry, Government College University, Faisalabad, 38000, Pakistan.
Department of Biochemistry, University of Agriculture, Faisalabad, Pakistan.
Environ Sci Pollut Res Int. 2022 Jan;29(1):564-572. doi: 10.1007/s11356-021-15669-6. Epub 2021 Jul 31.
The worldwide resurgence of natural dyes in all fields is due to the carcinogenic effects of effluent loads shed by synthetic industries. Coconut coir (Cocos nucifera) containing tannin as a source of natural colorants has been selected for coloration of bio-mordanted silk under the influence of ultrasonic radiations at various dyeing conditions. For extraction of tannin dye from cocos powder, different media were employed, and dyeing variables such as dyeing time, dye bath pH, dyeing bath temperature, and the effect of salts on dyeing were optimized. For achieving new shades with excellent color characteristics, bio-mordants in comparison with chemical mordants were employed. It has been found that acid-solubilized extract after ultrasonic treatment for 45 min has yielded high color strength, when coconut coir extract of 4 pH from 6g of cocos powder, containing 5g/100mL salt solution as exhaust agent, was used to dye silk at 75°C for 65 min. Among bio-mordants turmeric (K/S=13.828) and among chemical mordants iron has shown excellent results (K/S=2.0856). Physiochemical analysis of fabric before and after US treatment shows that there is no change in the chemical structure of the fabric. It is found that ultrasonic waves have excellent potential to isolate the colorant followed by dyeing and environmental friendly mordanting at optimal conditions, but also the usage of herbal-based plant anchors, i.e., bio-mordants, has made the natural dyeing process more sustainable and clean.
由于合成工业排放的废水负荷具有致癌作用，天然染料在各个领域的全球复兴已经出现。椰子纤维（Cocos nucifera）中含有单宁，是天然着色剂的来源，在各种染色条件下，它在超声波辐射的影响下被选择用于生物媒染丝的着色。为了从椰子粉末中提取单宁染料，使用了不同的介质，并优化了染色变量，如染色时间、染浴 pH 值、染浴温度以及盐对染色的影响。为了实现具有优异颜色特性的新色调，与化学媒染剂相比，使用了生物媒染剂。研究发现，经过 45 分钟超声处理的酸溶性提取物具有较高的色强度，当使用 4pH 的椰子纤维提取物（来自 6g 椰子粉，含有 5g/100mL 盐溶液作为排出剂），在 75°C 下对丝绸进行 65 分钟染色时，会产生这种效果。在生物媒染剂中，姜黄（K/S=13.828）和化学媒染剂铁（K/S=2.0856）都显示出了优异的效果。超声处理前后织物的物理化学分析表明，织物的化学结构没有变化。研究发现，超声波具有出色的潜力，可以在最佳条件下分离出着色剂，然后进行染色和环保的媒染，但草药植物锚固剂（即生物媒染剂）的使用也使天然染色过程更加可持续和清洁。
