|
| Effects of different carbon materials for enhancement of organic acid-mediated removal of heavy metals and nutrient retention in soil |
| Received:March 12, 2017 |
| View Full Text View/Add Comment Download reader |
| KeyWord:soil leaching;nano-carbon black;biochar;organic acid;composite leaching;heavy metals |
| Author Name | Affiliation | E-mail | | MA Xiao-jie | College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China | | | ZHANG Shi-rong | College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China | rsz01@163.com | | WANG Yi-jun | College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China | | | WANG Gui-yin | College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China | | | XU Xiao-xun | College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, China | | | LI Ting | College of Resources, Sichuan Agricultural University, Chengdu 611130, China | |
|
| Hits: 3192 |
| Download times: 3522 |
| Abstract: |
| Four carbon materials, including single nano-carbon black(NCB), rice straw biochar(RSB), wood biochar(WB), and nut-shell biochar(NSB), and two low molecular weight organic acids(citric acid and acetic acid) were tested alone and in combination to determine their efficacy for removal of soil Cd, Pb, and Zn. Single carbon materials showed removal efficiency of less than 0.5%. Generally, citric acid enhanced the removal of heavy metals by carbon materials more than acetic acid. Compared with citric acid alone, NCB significantly improved the efficiency of Cd, Pb, and Zn removal(10.1%~11.1%), whereas RSB enhanced removal efficiency less than NCB(7.8%~10.3%), and WB and NSB weakly increased the efficiency(1.8%~5.8%). The exchangeable, reducible, and partly oxidizable fractions of Cd, Pb, and Zn decreased markedly after washing with the mixed solutions(P<0.05). Soil organic carbon content increased by 8.7%~26.5% for all treatments, whereas total potassium decreased significantly relative to unwashed soils(P<0.05). The total nitrogen and phosphorus contents in different washed soils did not change significantly in comparison with original soils. Compared with single organic acids, the loss rates of available nitrogen, phosphorus, and potassium were reduced by 1.4%~6.1%, 4.4%~11.5%, and 1.3%~10.4%, respectively, in the presence of carbon materials. Therefore, addition of carbon materials, especially nano-carbon black and rice straw biochar, to organic acids could effectively enhance the efficiency of removal of soil heavy metals, as well as alleviate the loss of available soil nutrients. |
|
|
|
