Influences of pH and substrate supply on the ratio of iron to sulfate reduction
Influences of pH and substrate supply on the ratio of iron to sulfate reduction
复制标题
pH 值和底物供应对铁与硫酸盐还原比例的影响
DOI：
10.1111/gbi.12444
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发表时间：
2021
期刊：
影响因子：
3.7
通讯作者：
Kirk, Matthew F.
中科院分区：
文献类型：
--
作者：
Paper, Janet M.;Flynn, Theodore M.;Boyanov, Maxim I.;Kemner, Kenneth M.;Haller, Ben R.;Crank, Kathleen;Lower, AnneMarie;Jin, Qusheng;Kirk, Matthew F.
在缺氧系统中，铁还原和硫酸盐还原通常同时发生，在这种情况下，反应之间的摩尔比（即Fe/SO42−还原）会影响它们对水质和碳储量的影响。先前的研究表明，pH值和电子供体和受体的供应会影响这一比例，但尚不清楚它们的影响是如何相互比较和相互影响的。本研究考察了pH值、醋酸盐、硫酸盐和针铁矿的供应对半连续沉淀物生物反应器中铁与硫酸盐还原比的影响。我们检查了哪个参数对该比率的影响最大，以及参数的影响是否依赖于彼此的状态。结果表明：pH对铁/硫酸盐还原比的影响大于醋酸用量，且醋酸用量对铁/硫酸盐还原比的影响与pH有关。在酸性反应器（pH 6.0介质）中，随着醋酸用量的增加（0 ~ 1 mM），铁/硫酸盐还原比由3:1降至2:1。在碱性反应器（pH 7.5介质）中，铁和硫酸盐的还原比例相等，而不考虑醋酸盐的供应。其次，与不含硫酸盐的实验对比表明，硫酸盐还原时铁的还原程度更大，碱性反应器的效果比酸性反应器的效果更大。因此，硫酸盐供给对铁还原程度的影响也取决于pH值，表明随着pH值的增加，铁还原对硫酸盐还原的依赖性越来越强。我们的结果很好地与地下水地球化学趋势相比较，并提供了进一步的证据，证明pH值是晶体（氧）氧化物系统中铁和硫酸盐还原的主要控制因素。pH值不仅影响反应间的比值，还影响其他参数对该比值的影响。
Iron reduction and sulfate reduction often occur simultaneously in anoxic systems, and where that is the case, the molar ratio between the reactions (i.e., Fe/SO42−reduced) influences their impact on water quality and carbon storage. Previous research has shown that pH and the supply of electron donors and acceptors affect that ratio, but it is unclear how their influences compare and affect one another. This study examines impacts of pH and the supply of acetate, sulfate, and goethite on the ratio of iron to sulfate reduction in semi‐continuous sediment bioreactors. We examined which parameter had the greatest impact on that ratio and whether the parameter influences depended on the state of each other. Results show that pH had a greater influence than acetate supply on the ratio of iron to sulfate reduction, and that the impact of acetate supply on the ratio depended on pH. In acidic reactors (pH 6.0 media), the ratio of iron to sulfate reduction decreased from 3:1 to 2:1 as acetate supply increased (0–1 mM). In alkaline reactors (pH 7.5 media), iron and sulfate were reduced in equal proportions, regardless of acetate supply. Secondly, a comparison of experiments with and without sulfate shows that the extent of iron reduction was greater if sulfate reduction was occurring and that the effect was larger in alkaline reactors than acidic reactors. Thus, the influence of sulfate supply on iron reduction extent also depended on pH and suggests that iron reduction grows more dependent on sulfate reduction as pH increases. Our results compare well to trends in groundwater geochemistry and provide further evidence that pH is a major control on iron and sulfate reduction in systems with crystalline (oxyhydr)oxides. pH not only affects the ratio between the reactions but also the influences of other parameters on that ratio.
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影响因子：
5
作者：
Bonneville, Steeve;Behrends, Thilo;Van Cappellen, Philippe
通讯作者：
Van Cappellen, Philippe
DOI：
10.1038/ismej.2012.8
发表时间：
2012-08
期刊：
The ISME journal
影响因子：
--
作者：
通讯作者：
--
影响因子：
5
作者：
Cutting, R. S.;Coker, V. S.;Vaughan, D. J.
通讯作者：
Vaughan, D. J.
影响因子：
2.5
作者：
Ravel, B;Newville, M
通讯作者：
Newville, M
影响因子：
4.6
作者：
Jin, Qusheng;Kirk, Matthew F.
通讯作者：
Kirk, Matthew F.