Influence of Jatropha curcas seeds as a natural flocculant on reducing Tin (IV) tetrachloride in the treatment of concentrated stabilised landfill leachate. (December 2021)

• Record Type: Journal Article
• Authors: Zainal, Sharifah Farah Fariza Syed; Aziz, Hamidi Abdul; Omar, Fatehah Mohd; Alazaiza, Motasem Y.D.
• Is Part Of: Chemosphere. Volume 285(2021)
• Publication Date: 2021-12
• Subjects: Natural coagulant -- Leachate treatment -- Jatropha curcas -- Tetravalent metal salts -- Solid waste; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.131484
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Stabilised leachate usually contains lower concentration of organic compounds than younger leachate; it has low biodegradability and generally unsuitable for biological treatment. The effectiveness of tetravalent metal salts in a coagulation-flocculation (C–F) process is still inclusive. Application of natural coagulants as an alternative to the chemical could reduce chemical usage, is less costly, and environmentally friendly. Hence, the objective of the current research is to examine the possibility of reducing the amount of Tin (IV) chloride (SnCl4 ) as a primary coagulant by adding Jatropha curcas (JC) as a flocculant as a sole treatment through the C–F process in treating concentrated suspended solids (SS) (547 mg/L), colour (19, 705 Pt–Co) and chemical oxygen demand (COD) (4202 mg/L) in stabilised landfill leachate. The work also aims to evaluate the sludge properties after treatment. Functional groups, such as carboxylic acids, hydroxyl and amine/amino compounds (protein contents), were detected in the JC seed to facilitate the C–F process by neutralising the charge pollutant in water and cause the possibility of hydrogen bonding interaction between molecules. The combination of JC seed (0.9 g/L) as a flocculant reduced the dosage of SnCl4 as a coagulant from 11.1 g/L to 8.5 g/L with removals of 99.78%, 98.53% and 74.29% for SS, colour and COD, respectively. The presence of JC improved the sludge property with good morphology; the particles were in a rectangular shape, had clumps and strong agglomeration. These properties of sludge proved that JC seed could enhance the adsorption and bridging mechanism in the C–F procedure. Graphical abstract: Image 1 Highlights: The effectiveness of tetravalent metal-based coagulants is still inclusive. The application of Jatropha curcas (JC) seed aims to reduce SnCl4. 99.78, 98.53, and 74.29% reductions in SS, colour, and COD were obtained. Lower SnCl4 dosages maintained the same removal in the presence of JC. The treatment was carried out in a worst-case scenario with no other treatments.