摘要
生物炭性质虽然稳定,却也并非一成不变,其理化性质会随着时间推移而发生缓慢变化,进而对其功能产生影响。为明确陈化对生物炭理化性质的影响,探明生物炭陈化机制。以稻壳生物炭为试验材料,利用PVC圆柱,在人工气候箱中通过25个周期冻融循环(30℃/10d,-25℃/10d)和淋溶模拟生物炭陈化过程,分析生物炭表观结构、元素组成、氧化程度、吸附能力、pH值、碳酸盐含量等理化性质变化。结果表明:陈化处理破坏稻壳生物炭的表观结构、增加表面孔隙且随处理周期延长破坏程度加剧。C元素含量和C/H比值在25个周期中没有显著变化,C/N比值、速效P和N含量呈先下降后平稳趋势,速效K含量由7917mg·kg^(-1)下降到917mg·kg^(-1),达极显著水平。陈化处理初期生物炭表面O/C比值迅速上升,到第7个周期后开始下降,到15个周期后趋于平稳,说明陈化处理初期稻壳生物炭表面氧化迅速,后期则趋于平稳。陈化处理到25个周期时,生物炭对对苯二酚的吸附量由初始的5.93mg·g^(-1)增加到11.73mg·g^(-1),说明陈化处理增加了稻壳生物炭的吸附能力。陈化处理对pH值的影响呈先下降后上升,最后趋于平稳,且与原始生物炭pH值无显著差异。碳酸盐含量则呈现下降趋势至20个周期后趋于平稳。综合分析表明陈化处理对稻壳生物炭理化性质有一定影响,对其速效养分和吸附能力影响较显著。
The nature of biochar is stable, but it is not invariable. Its physical and chemical properties will change slowly over time, then impact its function. In order to clarify the influence of aging process on physical and chemical properties of biochar and its mechanism, rice husk biochar was used as the material, Using PVC column, 25 cycles of freeze-thaw cycles（30 ℃/10 d, -25 ℃/10 d）to simulate the biochar aging in climatic cabinet. The apparent structure, element composition, oxidation degree, adsorption capacity, pH value and carbonate content of biochar were analyzed. Results showed that aging damaged the biochar apparent structure, increase the surface pore with the cycles. Carbon element and the C/H ratio did not changed significantly, but the ratio of C/N, available P and N was decreased and then steady, available K from 7917 mg.kg-1 drop down to 917 mg＊kg-1 decreased significantly. At the initial stage of aging treatment, the surface O/C ratio of biochar increased rapidly, after the 7th cycle, it began to decrease, and reached to stable after the 15th cycle. It was showed that the surface oxidation of biochar was rapidly in early aging, the latter tended to stable. During the 25 cycles of aging, the adsorption capacity of biochar for hydroquinone increased from 5.93 mg＊g-1 to 11.73 mg＊g-1. So aging treatment increased the adsorption capacity of biochar. The pH value was decreased and then increased, tends to be stable. Finally there was no significant difference with the original biochar. The carbonate content showed a downward trend and tended to be stable in 20 cycles. Comprehensive analysis showed that aging treatment had affected physical and chemical properties of biochar, and had significant influences on its available nutrients and adsorption capacity.
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2017年第4期439-444,共6页
Journal of Shenyang Agricultural University
基金
辽宁省教育厅一般项目(L2015485
L2014256)
国家自然科学基金项目(41401325)
公益性行业(农业)科研专项项目(201303095)
关键词
稻壳生物炭
陈化
理化性质
rice husk biochar
aging
physical and chemical properties
