Changes of total and freely dissolved polycyclic aromatic hydrocarbons and toxicity of biochars treated with various aging processes.

The aim of this study was to determine the effect of biochar aging on the content of polycyclic aromatic hydrocarbons (PAHs) (the total content - C, and the freely dissolved - C) in biochar and its ecotoxicity. Two biochars (BCS and BCM) with varying properties were aged for 420 days at different temperatures (-20 °C, 4 °C, 20 °C, 70 °C), at a variable temperature (-20/20 °C), in the presence of nutrients, and in the presence of inoculum and nutrients. After the aging process, C and C PAHs were determined in samples obtained and an ecotoxicological analysis was performed, which involved tests with bacteria (Vibrio fischeri), invertebrates (Folsomia candida) and plants (Lepidium sativum).

Effect of co-application of nano-zero valent iron and biochar on the total and freely dissolved polycyclic aromatic hydrocarbons removal and toxicity of contaminated soils.

The aim of this study was to investigate co-application of biochar and nano zero-valent iron (nZVI) in order to increase the degradation of PAHs and reduce the toxicity of soils historically contaminated with these compounds. To performed the experiment biochar, biochar with nZVI (2 g kg or 10 g kg soil), or nZVI alone (2 g kg or 10 g kg soil) were added to the PAHs contaminated soils. The soils alone and soils with amendments were aged by mixing for 7 and 30 days.

Effect of biochar activation by different methods on toxicity of soil contaminated by industrial activity.

The objective of the study was to determine the effect of various methods of biochar activation on the ecotoxicity of soils with various properties and with various content and origin of contaminants. The biochar produced from willow (at 700°C) was activated by 1) microwaves (in a microwave reactor under an atmosphere of water vapour), 2) carbon dioxide (in the quartz fluidized bed reactor) and 3) superheated steam (in the quartz fluidized bed reactor). Three different soils were collected from industrial areas.

Effect of steam activated biochar application to industrially contaminated soils on bioavailability of polycyclic aromatic hydrocarbons and ecotoxicity of soils.

The aim of this study was to determine the effect of steam activation of biochars on the immobilization of freely dissolved (Cfree) and bioaccessible fraction (Cbioacc) of PAHs in soils. Additionally, the toxicity to various organisms like Vibrio fischeri, Lepidium sativum and Folsomia candida was measured before and after the amendment of biochars to soils. Three biochars produced from willow, coconut and wheat straw were steam activated and added to three different soils with varying content and origin of PAHs (coke vs.

Effect of activated carbon and biochars on the bioavailability of polycyclic aromatic hydrocarbons in different industrially contaminated soils.

Coal production negatively affects the environment by the emission of polycyclic aromatic hydrocarbons (PAHs). Two soils (KOK and KB) from a coking plant area was investigated and their total PAH concentration was 40 and 17 mg/kg for the sum (∑) 16 US EPA PAHs, respectively. A third soil was sampled from a bitumen plant area and was characterized by 9 mg/kg ∑16 US EPA PAHs.

Effect of activated carbon or biochars on toxicity of different soils contaminated by mixture of native polycyclic aromatic hydrocarbons and heavy metals.

Activated carbon (AC), biochar from wheat straw (BCS), and biochar from willow (BCW) were added to the soils sampled from areas of strong anthropogenic influence at doses of 0.5%, 1%, 2.5%, or 5% (w/w) and incubated for 2 mo.