A novel textile wastewater treatment using ligninolytic co-culture and photocatalysis with TiO2

Abstract

Textile industries produce effluent wastewater that, if discharged, exerts a negative impact on the environment. Thus, it is necessary to design and implement novel wastewater treatment solutions. A sequential treatment consisting of ligninolytic co-culture with the fungi Pleurotus ostreatus and Phanerochaete crhysosporium (secondary treatment) coupled to TiO 2 /UV photocatalysis (tertiary treatment) was evaluated in the laboratory in order to discolor, detoxify, and reuse textile effluent wastewater in subsequent textile dyeing cycles. After 48 h of secondary treatment, up to 80 % of the color in the wastewater was removed and its chemical and biochemical oxygen demands (COD, and BOD 5 ) were abated in 92 % and 76 %, respectively. Laccase and MnP activities were central to color removal and COD and BOD 5 abatement, exhibiting activity values of 410 U L −1 and 1 428 U L −1 , respectively. Subjecting wastewater samples to 12 h of tertiary treatment led to an 86 % color removal and 73 % and 86 % COD and BOD 5 abatement, respectively. The application of a sequential treatment for 18 h improved the effectiveness of the wastewater treatment, resulting in 89 % of color removal, along with 81 % and 89 % COD and BOD 5 abatement, respectively. With this sequential treatment a bacterial inactivation of 55 % was observed. TiO 2 films were reused continuously during two consecutive treatment cycles without thermic reactivation. Removal percentages greater than 50 % were attained. Acute toxicity tests performed with untreated wastewater led to a lethality level of 100 % at 50 % in Hydra attenuata and to a growth inhibition of 54 % at 50 % in Lactuca sativa. Whereas sequentially treated wastewater excreted a 13 % lethality at 6.25 % and an inhibition of 12 % at 75 % for H. attenuata and L. sativa, respectively. Finally, sequentially treated wastewater was reused on dyeing experiments in which 0.86 mg g −1 adsorbed dye per g of fabric, that is equivalent to 80 % of dye adsorption. AM. A novel textile wastewater treatment using ligninolytic co-culture and photocatalysis with TiO 2,

Phosphate-solubilizing Pseudomonas sp., and Serratia sp., co-culture for Allium cepa L. growth promotion

“…Soil was sterilized in two 15-minute autoclave cycles at 1.2 atm and 121 °C with a 24 h interval between cycles. Additionally, the soil was irradiated with UV light at 254 nm for 12 h, using a cubic photolysis reactor [ 42 ]. For seed planting 266 mL plastic cups containing 100 g soil were used.…”

LDPE Transformation by Exposure to Sequential Low-Pressure Plasma and TiO2/UV Photocatalysis

“…S3, the static contact angle, final weight, Young's modulus, an EDS analysis revealed that the Aldrich™ TiO 2 contained titanium (Ti) (8.90 wt%) and oxygen (O 2 ) (89.62 wt%) (Figure 5D). On the other hand, the XRD profile (Figure 5C), shows how the peak with the highest intensity is the orientation (A101), which corresponds to the anatase phase of TiO 2 [46,47].…”

Evaluación de la fotólisis, fotólisis/H2O2 y H2O2 como tratamientos para la reducción de Salmonella spp en aguas de granjas porcícolas

“…Posteriormente, se instalaron dos lámparas de luz ultravioleta con mercurio como gas inerte para tener una emisión máxima de 254 nm (Philips TUV 18, 15 W, longitud de onda 254 nm). Las lámparas se ubicaron sobre cada reactor, a 10 cm de distancia de cada uno (Blanco et al, 2018). En cada reactor se colocaron 500 ml de agua inoculada y las lámparas fueron encendidas durante 60 minutos; luego se retiró el agua, la cual fue utilizada para determinar el porcentaje de inactivación de Salmonella spp (Ecuación 1), la remoción de DQO (Ecuación 2) y el pH final.…”

“…Finalmente se realizaron cinéticas de inactivación/remoción valorando fotólisis UV 254 nm, fotólisis UV 254 nm con peróxido de hidrógeno H 2 O 2 a 15 ppm y peróxido de hidrógeno H 2 O 2 a 15 ppm. La inactivación de Salmonella spp se favoreció al emplear una aireación de 1 L/min y con una concentración de Salmonella spp de 1x10 4 UFCml -1 obteniendo una inactivación de 97.3±1.9% a los 10 minutos de tratamiento. Por otro lado, para las cinéticas de inactivación se estableció que los mejores tratamientos fueron fotólisis y fotólisis/ H 2 O 2 , sin que hubiera diferencias significativas.…”