Groupement de Recherche Eau, Sol et Environnement (GRESE), University of Limoges, 123 avenue Albert Thomas, 87060, Limoges, France.
Laboratory of Applied Chemistry (LCA), University Sidi Mohamed Ben Abdellah of Fez, Immouzer Road, BP 2202, Fez, Morocco.
Environ Sci Pollut Res Int. 2018 Apr;25(11):11111-11119. doi: 10.1007/s11356-018-1394-7. Epub 2018 Feb 7.
Opuntia ficus-indica that belongs to the Cactaceae family and is a member of Opuntia kind has received increasing research interest for wastewater treatment by flocculation. The objectives of this study were (i) to provide more information regarding the active constituents of Opuntia spp. and (ii) to improve the extracting and using conditions of the flocculant molecules for water treatment. A classic approach by jar test experiments was used with raw and extracted material by solubilization and precipitation. The surface properties of solid material were characterized by FTIR, SEM, zeta potential measurement, and surface titration. The splitting based on the solubility of the material with pH and the titration of functional groups completed the method. The optimal pH value for a coagulation-flocculation process using cactus solid material (CSM) was 10.0 and a processing rate of 35 mg L. The alkaline pH of flocculation suggests an adsorption mechanism with bridging effect between particles by water-soluble extracted molecules. To validate this mechanism, an extraction water was carried out at pH = 10 (optimum of flocculation) and the solution was acidified (pH = 7) to allow precipitation of so considered active flocculant molecules. The strong flocculant property of this extract was verified, and titration of this solution showed at least one specific pKa of 9.0 ± 0.6. This pKa corresponds to phenol groups, which could be assigned to lignin and tannin.
仙人掌果属于仙人掌科，是仙人掌属的一员，因其具有絮凝作用而受到越来越多的关注，可用于污水处理。本研究的目的是（i）提供更多关于仙人掌属植物活性成分的信息，（ii）改善絮凝剂分子用于水处理的提取和使用条件。采用经典的烧杯搅拌试验方法，使用溶胀和沉淀法对原料和提取物进行研究。通过傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）、动电位测量和表面滴定对固体材料的表面性质进行了表征。基于材料的溶解度与 pH 的分离和官能团的滴定完成了方法的建立。使用仙人掌固体材料（CSM）进行混凝-絮凝过程的最佳 pH 值为 10.0，处理率为 35mg/L。絮凝的碱性 pH 表明存在吸附机理，即通过水溶性提取分子在颗粒之间架桥。为了验证这一机制，在 pH=10（絮凝最佳 pH 值）下进行了提取水实验，并将溶液酸化（pH=7）以允许所谓的活性絮凝剂分子沉淀。该提取物具有很强的絮凝性能，并且该溶液的滴定表明至少有一个特定的 pKa 值为 9.0±0.6。该 pKa 值对应于酚基团，可归因于木质素和单宁。
