中国是世界上煤炭资源丰富的国家之一，煤炭是能源构成中的重要组成部分。在当今碳达峰和碳中和大环境下煤炭清洁和精细化使用成为研究的热点。而我国在2018年产生的固体废弃物就已有50亿吨，我国高度重视固废无害化处理及资源化利用等相关工作。因此，需要一种安全、经济、高效、环保的方案来实现将固体废弃物转化为能源的目的。

本实验从废弃资源利用角度着手，探究富含蛋白质的固体废物废旧皮革与煤的共热解反应，以及其产物中含氮化合物的种类及含量的变化，并以组成蛋白质的20种氨基酸作为皮革的更小结构单元，与煤进行共热解实验并研究其产物，最后将煤替换为模型化合物，从更小的分子层面入手，探究共热解反应的具体过程及产物的形成机制。将同位素示踪技术引入热解过程，为煤热解的机理研究提供路径支持。并且将煤和皮革等含氮物共热解，不仅可对热解焦油的组成定向调控从而对煤焦油的高值化利用提供帮助，还可对皮革类固体废弃资源的利用提供了方向。

主要工作如下：

(1) 探讨了煤与废旧皮革单独热解和共热解的产物特性及差异

使用红柳林低阶煤和废旧牛皮革分别进行单独热解和共热解实验，通过GC-MS等对其产物进行鉴定分析，发现煤单独的主要热解产物有长链的脂肪烃、芳香烃、含氧化合物及苯酚等，皮革单独热解产物有含氧化合物、胺类含氮物及杂环类含氮物等。而在的煤与皮革共热解条件下，可产生多种吡咯、吡啶、吡嗪等含氮杂环化合物，及(Z)-9-十八碳烯酰胺等多种由于共热解而产生的含氮物。

(2) 以氨基酸作为皮革的更小结构单元，探究其与煤的共热解作用及其产物特性

使用20种氨基酸替代皮革与红柳林煤分别进行共热解实验，探究其相互作用，发现煤与不同氨基酸的共热解，为热解焦油中增加了吡啶类、吡咯类、嘧啶类、腈类、胺类、酰胺类等多种在煤的单独热解中未出现的的含氮化合物。大幅提高了热解焦油中含氮化含量，且发现煤与皮革或氨基酸的共热解均会为产物中增加酰胺类物质。在煤与脯氨酸的共热解产物中，还产生了多种喹啉类化合物，包括喹啉、2-甲基喹啉、4-甲基喹啉及2,6-二甲基喹啉等多种有价值的含氮物。

(3)选用模型化合物和同位素示踪技术探究共热解反应具体产物的形成机制

选用取代基及位置不同的羟基苯甲腈、氨基苯甲腈和甲基苯甲腈作为模型化合物，分别选取氨基酸等不同氮元素形态的含氮物，研究不同含氮化合物在热解过程中的添加对产物的影响。并在反应过程中加入同位素对反应进行标记，探究具体键的断裂及形成过程。其中3-羟基苯甲腈+NH₄Cl/¹⁵NH₄Cl+H₂O/D₂O的共热解产物中，产生了4-氨基-α,α-4-三甲基-环己烷甲胺、苯酚、3-甲基苯酚以及2-甲氧基苯酚等带有同位素标记的产物，并据此提出了具体的自由基反应路径。

China is one of the world’s richest countries in terms of coal resources, and coal plays a significant role in the national energy structure. Under the current context of achieving carbon peaking and carbon neutrality, the clean and precise utilization of coal has become a focal point of research. In 2018, China generated 5 billion tons of solid waste, and the country places high importance on the harmless treatment and resource utilization of such waste. Therefore, there is an urgent need for a safe, economical, efficient, and environmentally friendly approach to convert solid waste into energy.

This study focuses on the utilization of waste resources, investigating the co-pyrolysis reaction between waste leather and coal, as well as the types and contents of nitrogen-containing compounds in the pyrolysis products. Additionally, the 20 amino acids that compose proteins are used as representative small structural units of leather, and their co-pyrolysis with coal is studied. Finally, coal is replaced with model compounds to explore the co-pyrolysis process and product formation mechanisms at the molecular level. Isotope tracing technology is introduced into the pyrolysis process to provide insights into the mechanism of coal pyrolysis. Moreover, the co-pyrolysis of coal and nitrogen-containing materials such as leather not only enables targeted regulation of the composition of pyrolysis tar but also provides guidance for the high-value utilization of coal tar and the resource utilization of leather-based solid waste.

The main work includes the following:  

1. Separate pyrolysis and co-pyrolysis experiments were conducted using Hongliulin low-rank coal and waste cowhide. The pyrolysis products were analyzed using GC-MS. It was found that the main pyrolysis products of coal alone include long-chain fatty hydrocarbons, aromatic hydrocarbons, oxygen-containing compounds, and phenols. The pyrolysis products of leather alone include oxygen-containing compounds, amine-containing nitrogen compounds, and heterocyclic nitrogen compounds. However, during the co-pyrolysis of coal and leather, multiple nitrogen-containing heterocyclic compounds such as pyrrole, pyridine, and pyrazine, as well as (Z)-9-octadecenamide, were generated due to the co-pyrolysis process.  

2. Using 20 amino acids as substitutes for leather, co-pyrolysis experiments were conducted with Hongliulin coal to investigate their interactions. It was discovered that the co-pyrolysis of coal with different amino acids significantly increased the nitrogen content in pyrolysis tar and introduced various nitrogen-containing compounds, such as pyridine, pyrrole, pyrimidine, nitrile, amine, and amide compounds, which were not present in the pyrolysis of coal alone. Notably, the co-pyrolysis of coal with proline produced valuable nitrogen-containing compounds, including quinoline, 2-methylquinoline, 4-methylquinoline, and 2,6-dimethylquinoline.  

3. Model compounds with different substituents and positions, such as hydroxybenzocyanide, aminobenzocyanide, and methylbenzocyanide, were selected. Additionally, nitrogen-containing compounds with different nitrogen forms, such as amino acids, were chosen to study the effects of different nitrogen-containing compounds on the pyrolysis products. Isotopes were introduced into the reaction to track the breaking and forming of chemical bonds. For example, the co-pyrolysis of 3-hydroxybenzocyanide with NH₄Cl/¹⁵NH₄Cl and H₂O/D₂O produced isotopically labeled products, such as 4-amino-α,α-4-trimethylcyclohexanemethanamine, phenol, 3-methylphenol, and 2-methoxyphenol. Based on these observations, a specific radical reaction pathway was proposed.