Abstract:

This review introduces the production, modification and characterization of biochar, especially its application in environment remediation. Pyrolysis, gasification and hydrothermal carbonization are the common methods for biochar production. The adsorption properties of biochar are influenced by the raw materials and production conditions. To improve the adsorption properties of biochar, it can be modified by acid, alkali, oxidizing agents, metal ions, organic compound, ultraviolet radiation, non-thermal plasma, combined materials, steam and gas purging. The selected modification methods depend on the fields of environment application. Although biochar has been used for soil remediation and improvement, carbon sequestration, organic solid waste compost, decontamination of water and wastewater, air pollution control with great success, however, whether biochar could sequester carbon needs further investigation at different soil conditions; the reasons why biochar improves soil quality need to be further study; the mechanism of organic pollutants removal by biochar in soils needs further investigation. In addition, more attention should be paid to the stability of biochar to avoid secondary pollution when biochar is used for environment remediation. In summary, biochar has a broad application prospect in environment remediation but there are still some problems and challenges to be solved.

Key words: biochar, characterization, modification, adsorption, environment remediation

摘要：

介绍了生物炭的制备、改性及表征，尤其是在环境修复中的应用。阐述了生物炭常用的制备方法包括热解法、气化法和水热碳化法，指出生物炭的制备原料和条件决定了生物炭的吸附性能。为了提高生物炭的吸附性能，常通过酸、碱、氧化剂、金属氧化物、有机化合物、紫外辐射、等离子体、复合材料、蒸汽及气体吹扫等方式对其进行改性处理，而改性方法的选择主要取决于应用的环境领域。虽然生物炭已在土壤修复及改良、固碳、有机固废堆肥、废水净化及大气污染治理等领域取得了良好的效果，但是生物炭的固碳效果还需要在不同土壤条件进一步验证，生物炭提高土壤质量的原因还需要进一步研究，生物炭去除土壤中有机污染物的作用机理也有待进一步探明。此外，利用生物炭进行环境修复时，应注意生物炭的稳定性问题，以免造成二次污染。综上所述，生物炭在环境修复中具有广阔的应用前景，但也存在一些问题和挑战需要解决。

关键词: 生物炭, 表征, 改性, 吸附, 环境修复