盐酸羟胺促进分级Fenton氧化土壤长链原油的试验研究

H₂O₂分次投加可以提高石油烃(total petroleum hydrocarbons,TPH)去除率,本试验选用900 mmol/L H₂O₂分3次投加的方式进行分级Fenton氧化修复长链原油污染土壤。在Fe²⁺、固相铁、Fe²⁺+盐酸羟胺、固相铁+盐酸羟胺4种催化体系下进行试验,发现在向Fe²⁺体系和固相铁体系加入盐酸羟胺后,后两级反应·OH强度明显增强,是未加入盐酸羟胺体系下的3倍～4倍,TPH及长链烃氧化量也大幅提高。采用向Fenton体系中加入盐酸羟胺的方式,克服了分级Fenton氧化过程中由于Fe²⁺不足导致·OH强度较第一级显著降低、TPH及长链烃氧化量大幅下降的缺陷,促进了后两级反应过程中·OH的产生,从而大大提高了后两级TPH及长链烃的去除效果,使后两级去除效果与第一级接近,能够维持在较高水平,为急需短时间进行的土壤修复提供了一定的理论依据。

Experimental Study of Hydroxylamine Hydrochloride on Improving Fenton Oxidation of Long Chain Crude Oil in Soil

The TPH removal rate can be improved by stepwise addition of H2O2, and the 900mmol/L H2O2 is divided into 3 times for stepwise Fenton oxidation to remediate the polluted soil of long chain oil in this research. Experimental research was conducted under the four catalysis system of Fe2+, solid iron, Fe2++ hydroxylamine hydrochloride, solid iron + hydroxylamine hydrochloride. It was found that the ·OH intensity is significantly higher facilitated when the hydroxylamine hydrochloride was added to Fe2+ system and solid iron system, which was 3-4 times to the system without hydroxylamine hydrochloride. The TPH and the long chain hydrocarbon oxidation amount was also greatly increased. Because of the lack of Fe2+, the ·OH intendity was significantly lower than at the first stage and the oxidation of TPH and long chain hydrocarbons was greatly reduced. Hydroxylamine hydrochloride could overcome these shortcomings, the ·OH produced in second and third stage was significantly facilitated, thus the TPH and long chain hydrocarbon removal efficiency was greatly improved, that was close to the first stage and can maintain at a higher level. So the study could provide a certain theoretical basis for the urgent need for short-term soil remediation.