Mol Annemerel R, Meuwissen Derek J M, Pruim Sebastian D, Zhou Chenyu, van Vught Vincent, Klok Johannes B M, Buisman Cees J N, van der Weijden Renata D
Environmental Technology, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
Paqell B.V., Reactorweg 301, 3542 AD Utrecht, The Netherlands.
ACS Omega. 2021 Oct 18;6(42):27913-27923. doi: 10.1021/acsomega.1c03701. eCollection 2021 Oct 26.
This article presents a novel crystal agglomeration strategy for elemental sulfur (S) produced during biological desulfurization (BD). A key element is the nucleophilic dissolution of S by sulfide (HS) to polysulfides (S ), which was enhanced by a sulfide-rich, anoxic reactor. This study demonstrates that with enhanced S formation, crystal agglomerates are formed with a uniform size (14.7 ± 3.1 μm). In contrast, with minimal S formation, particle size fluctuates markedly (5.6 ± 5.9 μm) due to the presence of agglomerates and single crystals. Microscopic analysis showed that the uniformly sized agglomerates had an irregular structure, whereas the loose particles and agglomerates were more defined and bipyramidal. The irregular agglomerates are explained by dissolution of S by (poly)sulfides, which likely changed the crystal surface structure and disrupted crystal growth. Furthermore, S from S appeared to form at least 5× faster than from HS based on the average S chain length of ≈ 5, thereby stimulating particle agglomeration. In addition, microscopy suggested that S crystal growth proceeded via amorphous S globules. Our findings imply that the crystallization product is controlled by the balance between dissolution and formation of S. This new insight has a strong potential to prevent poor S settleability in BD.
本文提出了一种针对生物脱硫（BD）过程中产生的元素硫（S）的新型晶体团聚策略。一个关键因素是硫化物（HS）将S亲核溶解为多硫化物（S ），这在富含硫化物的缺氧反应器中得到了增强。本研究表明，随着S 的形成增加，会形成尺寸均匀（14.7±3.1μm）的晶体团聚体。相比之下，在S 形成极少的情况下，由于团聚体和单晶的存在，颗粒尺寸会显著波动（5.6±5.9μm）。显微镜分析表明，尺寸均匀的团聚体具有不规则结构，而松散颗粒和团聚体则更规则且呈双锥体形状。不规则团聚体可通过（多）硫化物对S的溶解来解释，这可能改变了晶体表面结构并扰乱了晶体生长。此外，基于平均S 链长约为5，来自S 的S似乎比来自HS的S形成速度至少快5倍，从而促进了颗粒团聚。此外，显微镜观察表明S晶体生长通过无定形S球进行。我们的研究结果表明，结晶产物受S溶解与形成之间平衡的控制。这一新见解对于防止BD中S沉降性能不佳具有很大潜力。
