生物质洗脱过程中矿物质和分子结构的变化

Study on the Change of Minerals and Molecular Structure during Biomass Washing Process

实验选用鄱阳湖典型水生植物芦苇为研究对象,通过水洗和酸洗制取相应的生物质样,低温灰化并采用XRF进行灰成分分析,结合傅立叶红外光谱法分析了生物质在洗脱过程中分子结构的变化。研究发现芦苇的灰分中无机盐占99.8%,其中含水溶性盐占矿物质12.47%,难溶或不溶于水的矿物质占87.33%,有机矿物质只有0.2%。芦苇中矿物质的主要成分为Si,其次是S、K、Al、Ca、P、Mn和Fe,水洗对含S、K、Ca等矿物质的影响较为明显。芦苇的分子结构红外谱图在特征峰区和指纹区都有缔合吸收峰,且含有较多的直链和单键支链,存在较多的含氧基团,主要包括羰基、羧基、酸酐基团等。酸洗主要脱除了游离的N-H基团和Si-O基团,对有机硫基团的影响较小。

The typical aquatic plant in Poyang Lake, Reed, was uesd as the object in this experiment, and the samples were prepared by washing with water and acid. Low-temperature ashing and X-ray fluorescence （XRF） were used to analyze the ash compositions, and molecular structure was ana- lyzed by Fourier infrared spectrum （RI＇IR）. The resuhs show that inorganic minerals in Reed almost is 99.8%, in which the water-soluble salt is 12.74%, water-indissolvable or water-insoluble salts 87.06%, and organic minerals is 0.2%. The main minerals are Si in Reed, followed by S, K, A1, Ca, P, Mn and Fe. It is obviously that most of S, K and Ca are removed by water-washed. There are association absorption peaks in the characteristic peak area and the fingerprint area of the infrared spectrum of Reed, and there are more linear chain and single-bond branched chain. There are more oxygen-containing groups, mainly including carbonyl groups carboxyl groups, and anhydride groups, etc. N-H groups and Si-O groups are washed out during Acid washing, but acid washing is little ef- fective to organic sulfur groups.