Smith Megan M, Silva Jeff A K, Munakata-Marr Junko, McCray John E
Hydrologic Science & Engineering Program and Environmental Science & Engineering Division, Colorado School of Mines, Golden, Colorado 80401, USA.
Environ Sci Technol. 2008 Dec 15;42(24):9296-301. doi: 10.1021/es800757g.
Polymer floods provide a promising method to more effectively deliver conventional groundwater treatment agents to organic contaminants distributed within heterogeneous aquifer systems. Combinations of nontoxic polymers (xanthan and hydrolyzed polyacrylamide) and common chemical oxidants (potassium permanganate and sodium persulfate) were investigated to determine the suitability of these mixtures for polymer-enhanced in situ chemical oxidation applications. Oxidant demand and solution viscosity were utilized as initial measures of chemical compatibility. After 72 h of reaction with both test oxidants, solution viscosities in mixtures containing hydrolyzed polyacrylamide were decreased by more than 90% (final viscosities approximately 2 cP), similar to the 95% viscosity loss (final viscosities approximately 1 cP, near that of water) observed in xanthan/persulfate experiments. In contrast, xanthan solutions exposed to potassium permanganate preserved 60-95% of initial viscosity after 72 h. Permanganate depletion in xanthan-containing experiments ranged from 2% to 24% over the same test period. Although oxidant consumption in xanthan/permanganate solutions appeared to be correlated with increasing xanthan concentrations, solutions of up to 2000 mg/L xanthan did not inhibit permanganate from oxidizing a dissolved-phase test contaminant (tetrachloroethene, PCE) in xanthan solution. These advantageous characteristics (high viscosity retention, moderate oxidant demand, and lack of competitive effects on PCE oxidation rate) render xanthan/permanganate the most compatible polymer/oxidant combination of those tested for remediation by polymer-enhanced chemical oxidation.
聚合物驱油提供了一种很有前景的方法，能更有效地将传统地下水处理剂输送到非均质含水层系统中分布的有机污染物处。研究了无毒聚合物（黄原胶和水解聚丙烯酰胺）与常见化学氧化剂（高锰酸钾和过硫酸钠）的组合，以确定这些混合物用于聚合物强化原位化学氧化应用的适用性。氧化剂需求量和溶液粘度被用作化学相容性的初步衡量指标。与两种测试氧化剂反应72小时后，含水解聚丙烯酰胺的混合物中的溶液粘度降低了90%以上（最终粘度约为2厘泊），这与黄原胶/过硫酸盐实验中观察到的95%的粘度损失（最终粘度约为1厘泊，接近水的粘度）相似。相比之下，暴露于高锰酸钾的黄原胶溶液在72小时后保留了60 - 95%的初始粘度。在相同的测试期间，含黄原胶的实验中高锰酸盐的消耗量在2%至24%之间。尽管黄原胶/高锰酸盐溶液中的氧化剂消耗似乎与黄原胶浓度的增加相关，但高达2000 mg/L黄原胶的溶液并未抑制高锰酸盐氧化黄原胶溶液中溶解相的测试污染物（四氯乙烯，PCE）。这些有利特性（高粘度保留、适度的氧化剂需求以及对PCE氧化速率缺乏竞争效应）使黄原胶/高锰酸盐成为聚合物强化化学氧化修复测试中最相容的聚合物/氧化剂组合。
