褐煤黄腐酸解离纯化及分子结构识别的基础研究

Extraction of coal based fulvic acid is a new way to realize the efficient conversion and utilization of the low grade lignite. Green extraction and purity requirements of fulvic acid from lignite need the innovation of fulvic acid extraction technology and mechanism breakthrough..Through theoretical analysis, experimental research, mathematical modeling，and with the help of mineral processing and chemical disciplines, the project developed an innovation of "Microwave-Solvent Method" . Using low grade lignite as the test sample, firstly, the lignite was weathered and pre-treated by H2O2. Efficient weathering conditions, oxidation conditions and theoretical basis were studied. Then, oxidized lignite was extracted selectively by microwave, and fulvic acid crude products were obtained. Mechanisms and conditions of microwave extraction of fulvic acid were established with the help of software design, multi scale product analysis, and mathematical modeling. On this basis, using sulfuric acid convert fulvic acid salt to fulvic acid, and high purity fulvic acid was prepared by acetone extraction. Micro mesoscopic morphology, chemical composition, and molecular features of fulvic acid cluster were charactered. Kinetics and optimal conditions were revealed in the process of conversion and extraction separation. Tthe basic theory and technical system of of high purity fulvic acid efficient extraction were comprehensively constructed in the project. This project provides the reference for the research on the theory and technology of fulvic acid, and promotes the innovation and development of related disciplines.

煤基黄腐酸提取是实现低品位褐煤高效转化利用的新兴途径，实现褐煤黄腐酸环保提取和纯度要求，需要创新黄腐酸提取技术方法及机理研究的科学突破。.本项目通过理论分析、试验研究与数学建模相结合的手段，利用矿物加工与化工等学科知识交叉融合创新构建“微波-溶剂法”展开研究。项目以低品位褐煤为试验样本，首先对褐煤风化及H2O2氧解预处理，研究高效风化氧解条件参数与理论基础。再用微波选择性抽提氧解后褐煤，得黄腐酸粗制品；借助软件设计、多尺度产物检测表征、数学建模等，建立微波抽提黄腐酸作用机理与条件参数。在此基础上，硫酸转化粗产品中黄腐酸盐为黄腐酸，通过丙酮萃取分离制得高纯黄腐酸，测试表征分析黄腐酸团簇微介观形貌及化学、分子构成特征，揭示转化与萃取分离过程中的动力学规律及优化条件。最后综合构建微波-溶剂法高效抽提高纯黄腐酸的基础理论与技术体系，为黄腐酸理论与技术研究提供参考，促进相关学科创新发展。

黄腐酸在现代农业、生态恢复、水处理及生命科学等领域有重要功效和广泛应用，然而，黄腐酸环保、高效的提取技术及其分子结构的科学识别研究薄弱。本项目针对传统煤基黄腐酸提取方法产率低、药剂污染大的问题，以低品位褐煤为试验样本，创新构建“微波-溶剂法”提取褐煤黄腐酸，经纯化后获得高纯黄腐酸；研究通过煤化学、有机化学、物理化学、化工及分子结构理论等多学科理论技术知识创新交叉协同，借助元素分析、红外、紫外、氢核磁、碳核磁、GC/MS等先进手段分析表征，获得黄腐酸团簇微介观形貌及化学、分子构成特征，结合软件模拟及量子化学构建了黄腐酸分子结构模型，并进行验证分析与理论研究。项目取得的重要结果和关键数据有：（1）氧解提取过程创新引进环保高效微波技术可促进过氧化氢提取褐煤黄腐酸；（2）微波-过氧化氢体系中加入冰醋酸或甲酸，可显著提高黄腐酸提取率；通过选择适宜煤种，采用微波-过氧化氢-冰醋酸提取褐煤黄腐酸，提取率可达60%；（3）通过控制反应条件可明显增加黄腐酸的氧含量和羧基含量，所得黄腐酸水溶性好；（4）建立“微波-溶剂法”提取黄腐酸动力学模型的反应速率方程；（5）构建了黄腐酸分子结构建立的过程技术、3D模型与相关基础理论；（6）揭示黄腐酸分子结构中苯环是中心组成部分，各分子支链及官能团与苯环结构通过醚氧桥键相互连接；含氧官能团分布较多，其中羧基、酚羟基及羰基占据大部分，其中羧基含量最高；羧基主要存在于脂肪结构末端，分子结构中羧基及酚羟基的存在使其具有良好水溶性和生化活性。综上，本项目成功构建了“微波-溶剂法”环保高效提取褐煤黄腐酸的新途径，揭示了转化分离过程中的动力学规律及黄腐酸微观分子化学结构，为黄腐酸理论与技术研究提供参考，也为黄腐酸在生命科学、化学医药及水处理等众多领域应用奠定了科学基础。