Abstract:Iron-carbon composites(Fe/C pH2、Fe/C pH4、Fe/C pH6、Fe/C pH8、Fe/C pH10) were synthesized by hydrothermal-carbonization method using sucrose and anhydrous ferric chloride as raw materials and adjusting the pH of solution with ammonia. Fe/C pH10 was further prepared iorn-carbon composite material(Fe/C pH10-Q) with a particle size in the range of 100~1000 nm by ball milling method. The adsorption and degradation properties of product for trichloroethylene (TCE) were investigated. The morphology and composition of the products prepared at different pH were characterized by SEM, XRD, TG, N2 adsorption-desorption. Gas chromatography (GC) and ion chromatography (IC) were used for quantitative determination of TCE and degradation products (ethane, ethylene and chloride ions). The results showed that nano-zero-valent iron (nZVI) co-existed with biochar in iron-carbon composites, nZVI was randomly dispersed over carbon spheres or particles, agglomeration don’t occurred. The content and particle size of nZVI in the product increased to 36.35%、60 nm of Fe/C pH10 from 6.52%、20 nm of Fe/C pH2 as solution pH increased. The specific surface area of the product decreased to 302 m2/g of Fe/C pH10 from 369 m2/g of Fe/C pH2. The degradation rate of TCE by Fe/C composites was in the order of Fe/C pH10>Fe/C pH8>Fe/C pH6>Fe/C pH4>Fe/C pH2. The removal rate of TCE was closed to 100% by Fe/C pH10 when reaction time was 48 h. The particle size, content and reactivity of nZVI in Fe/C composites were not changed by ball milling. The transport performance of Fe/C pH10-Q was evaluated by quartz sand column, results showed that Fe/C pH10-Q had satisfactorilly underground transmission performance. Liquidity of Fe/C pH10-Q significantly increased by compared with commercial nZVI and Fe/C pH10