Degradation characteristics of dissolved organic matter in nanofiltration concentrated landfill leachate during electrocatalytic oxidation

Characterization and photodegradation pathway of the leachate of Matuail sanitary landfill site, Dhaka South City Corporation, Bangladesh

“…All three samples had five major peak regions, notably at 3440–3450 cm −1 , 1638 cm −1 , 1385 cm −1 , 1115 cm −1 , and 605 cm −1 . The broad stretching band at 3440–3450 cm −1 belongs to the bonded and non-bonded O–H groups of water ( Huo et al., 2008 , 2009 ; Zhang et al., 2020 ). In the raw leachate sample, the band peak was not prominent, while 2 nd -day and 5 th -day photo-treated samples showed a distinct broad peak of O–H stretching.…”

“…The small but sharp peaks at 1638 cm −1 related to the C=O Amide I, carboxylates C=C, aromatic ring modes, or alkenes. The band Wavenumbers 1385-90 cm −1 might belong to the deformation of the C–H bond in CH 2 and CH 3 , or the asymmetric stretching of COO¯( Huo et al., 2009 ; Zhang et al., 2020 ). The broad peak at 1115 cm −1 might be related to stretching the C–O bond in phenol ethers and phenols.…”

“…The broad peak at 1115 cm −1 might be related to stretching the C–O bond in phenol ethers and phenols. A weak band at 595 cm −1 in the raw sample and a distinct broad peak on the 2 nd day and 5 th -day photo-treated sample might belong to the S–O bends of sulfates ( Huo et al., 2009 ; Zhang et al., 2020 ). The spectrum identified by FTIR indicates the presence of complex molecular structure of the DOMs present in the landfill leachates that changed structures upon photo-treatment with sunlight.…”

“…(2009) identified 6 fluorophores in their leachate study: Ex 240, 310, 360 nm/Em 460 nm; Ex 220, 280/Em 340 nm; Ex 220, 270 nm/Em 300 nm; Ex 220, 280 nm/Em 360 nm; Ex 230, 320 nm/Em 420 nm; and Ex 220, 310 nm/Em 400 nm ( Lu et al., 2009 ). Ex 260/Em 450 nm and Ex 330/Em 410 nm are closely associated with humic-like acid ( Zhang et al., 2020 ). Furthermore, multiple Ex 240–243, 262–272, 306–343 nm/Em 373–398 nm might belong to the pyrene and its alkyl derivates ( He et al., 2016 ).…”

“…Lu et al (2009) (Lu et al, 2009). Ex 260/Em 450 nm and Ex 330/Em 410 nm are closely associated with humic-like acid (Zhang et al, 2020). Furthermore, multiple Ex 240-243, 262-272, 306-343 nm/Em 373-398 nm might belong to the pyrene and its alkyl derivates (He et al, 2016).…”