Welcome to visit Geoscience!

Geoscience ›› 2021, Vol. 35 ›› Issue (04): 931-939.DOI: 10.19657/j.geoscience.1000-8527.2021.04.04

• Geochemistry • Previous Articles     Next Articles

Effects of High Temperature and Freeze-thaw Cycle Ageing on Adsorption Performance of Hydrochar and Biochar on Pollutants

GUAN Junjie1,2(), LIU Yuyan1,2, LIU Siyuan1,2, CHEN Jiawei1,2()   

  1. 1. State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China
    2. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China
  • Received:2019-12-17 Revised:2021-04-19 Online:2021-08-10 Published:2021-09-08
  • Contact: CHEN Jiawei

Abstract:

The application of hydrochar or biochar derived from agricultural wastes into soil amendments and remediation is one of hot topics nowadays. Due to long-term varied natural condition, such as changed ambient temperature, the properties of hydrochar or biochar would change and have some effect on the adsorption capacities. Hence, it is an important issue to assess the adsorption performance of hydrochar and biochar under the effect of ageing. In the study, high temperature ageing and freeze-thaw cycle ageing were used to simulate the changed ambient temperature. The physicochemical properties of fresh and aged rice husk and corn straw derived biochars and hydrochars were compared by multi-techniques of elemental analysis, Fourier infrared spectrometer (FTIR) and scanning electron microscope (SEM). The adsorption capacity and stability of hydrochar and biochar, as well as the effects of different ageing time (e.g., 30, 60, 90 cycles) on their adsorption capacity, were compared by batch experiments. The results showed that biochar had good adsorption stability for Cd (II) and atrazine, while hydrochar had poor adsorption stability for atrazine. The two ageing processes increased the oxygen containing functional groups of hydrochar and biochar, thus enhancing the adsorption capacity of Cd (II) and atrazine. In high temperature and freeze-thaw environment, biochar was more susceptible to environmental effects than hydrochar as the ageing time increased. The obtained results from this study suggest us to consider the rational use of hydrochar and biochar in the environmental remediation.

Key words: biochar, hydrochar, ageing, pollutant, adsorption ability

CLC Number: