摘要
以废弃生物质松子壳为原料,利用水热碳化法在180~250℃下制备生物炭,考察添加金属离子(Ca^(2+)、Zn^(2+)、Al^(3+)和Fe^(3+))对松子壳生物炭的影响。通过元素分析、傅里叶红外光谱、扫描电子显微镜等技术对松子壳生物炭的结构进行了分析和表征。结果表明,4种金属离子均对松子壳水热碳化起到促进作用,金属离子的加入可在较低温度下得到具有较高碳含量及热值的生物炭。添加金属离子的水热炭化过程在180~230℃以脱水为主,伴随脱羧反应,在230~250℃以脱甲烷化为主。在4种金属离子中,Fe^(3+)对松子壳水热碳化的促进作用最大,温度180℃时,添加Fe^(3+)所得生物炭的碳含量和热值分别为66.59%和24.40 MJ·kg^(-1),是在纯水中180℃时生物炭的碳含量的1.29倍,热值的1.31倍。在扫描电镜中发现添加Fe^(3+)生成的生物炭出现的球形结构较多。通过调节温度以及添加适合的金属离子可实现对炭微球的粒径及数量的控制。
The influences of metal ions（ Ca^（2＋）,Zn^（2＋）,Al^（3＋）,Fe^（3＋）） on hydrothermal carbonization（ HTC） for wasted pinenut shells to biochar at 180 to 250 ℃ were studied. The biochars were investigated using elemental analyses,Fourier-transform infrared spectroscopy（ FTIR）,and scanning electron microscopy（ SEM） to obtain detailed chemical and structural characteristics. The results showed that the four metal ions have positive effects on HTC： the biochars produced by adding metal ions have higher C contents and higher heating values（ HHVs） at lower temperatures. The HTC process might involve dehydration and decarboxylation at 180 to 230 ℃,and demethanation at 230 to 250 ℃ when adding metal ions. Fe^（3＋） had the most remarkable effect on HTC among the four metal ions studied. The C content and HHV of the biochar were 66. 59% and 24. 40 MJ·kg^（-1）with Fe^（3＋） at180 ℃,which were 1. 29 times and 1. 31 times compared with that in the pure water,respectively. Greater number of carbon microspheres was observed in the biochar by SEM on adding Fe^（3＋）. The size and amount of microspheres can be controlled by adjusting the temperature and suitable metal ion additives.
出处
《环境工程学报》
CAS
CSCD
北大核心
2016年第7期3841-3847,共7页
Chinese Journal of Environmental Engineering
关键词
水热碳化
生物炭
松子壳
金属离子
hydrothermal carbonization（HTC）
biochar
pinenut shell
metal ion
