低浓度酸对糖类物质的碳化现象研究

能源是经济与社会发展的基本动力，随着全球经济发展以及世界人口的增长，能源与环境的危机也日渐凸显。所以开发可再生能源成为减碳和实现社会可持续发展的必然选择。目前，生物质因具有CO₂零排放不会造成温室效应的特点，被公认是一种优质的燃料。但是生物质同时具有含氧量高和含碳量少的特点，而碳含量对于生物质燃烧在释放能量方面具有积极的作用，氧含量则起到负面作用。所以生物质也存在不抗烧，热值低等缺点。本实验的目的是找到一种可以提高生物质碳含量和降低氧含量的方法。糖类物质是生物质的重要组成部分，本工作采用了不同浓度的盐酸、硫酸和高氯酸分别与糖类物质在常温常压条件下进行碳化反应。并通过X射线光电子能谱(XPS)、元素分析和显微红外分析等方法对碳化残余物质进行表征，结果发现样品的碳含量都有了明显的增加并且伴随着氧含量的下降。同时，通过滴定的方法发现各种酸都有少量的消耗，可以用于循环利用，减少酸污染。值得提出的是，本实验所有的反应都是在常温常压零能耗的条件下进行的，这大大减少了其他能源的消耗，减少环境危机。所以本研究为可能改善生物质燃料燃烧的特性，降低能源利用带来的环境污染和产生更高能量密度能源物质提供了新的机会。

Studies on Carbonization of Saccharides by Using Aqueous Solution of Various Acids

The authors tried to establish an approach to use acids to convert biomass into a fuel with higher carbon content and lower oxygen content in a zero-energy-consumption fashion. Considering that biomass is composed of monosaccharide, we used aqueous solutions of variation acids including hydrochloric acid, sulfuric acid and perchloric acid to treat 2-deoxy-ribose and fructose at ambient temperature and pressure. Black substances were produced after a period of time when 2-deoxy-ribose and fructose were mixed with aqueous solutions containing 8 mol·L-1 acids. The black substance was collected and characterized by using elemental analysis, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Elemental analysis results indicate that the contents of carbon increases significantly in the black substances in comparison with 2-deoxy-ribose and fructose. Moreover, XPS results indicate that the content of oxygen in the black substance undergoes a significant decrease comparedwith pure 2-deoxy-ribose and fructose. In the XPS spectra, the 1s peaks of 2-deoxy-ribose, strong sub peak at 286.05 eV, which is assigned to carbon linked to oxygen directly, dominate in the C 1s peak envelop. After treatment by HClO₄, the peak decreased dramatically. This result also supports the conclusion that the content of oxygen in mono-saccharide is significantly reduced after treatment by acids. In the FTIR spectra of the black substances, strong peaks can be observed around 1 600 cm-1, indicating that CC bond is formed in the product. The above results suggest that treatments with acids may be developed as a new zero-energy-consumption approach to convert biomass in a new fuel with improved energy output efficiency.