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Intensive animal farming produces large volume of digested liquid, and overdose application often causes the pollution of surface water and groundwater. Therefore, post-treatment is very necessary for the discharging of surplus digested liquid, but the removal of high concentrations of suspended solids (SS) in the digested liquid is a challenge. In this study, the effect of Ca(ClO) 2 pretreatment on SS flocculation removal of digested dairy wastewater was investigated. The results showed that, without Ca(ClO) 2 pretreatment, the flocculation by polyacrylamide (PAM), polyferric sulfate (PFS) or polymeric aluminum chloride (PAC) only removed 42.6 %-50.4 % SS from anaerobic digested liquid. With the combination of Ca(ClO) 2 pretreatment and PAC flocculation together, the SS removal efficiency can reach 80 %. The total chemical oxygen demand (TCOD) removal had a similar trend with SS removal, but soluble chemical oxygen demand (SCOD) removal was less affected by the pretreatment and flocculation. More than 75 % of orthophosphate (SRP) and total soluble phosphorus (TSP) was removed after Ca(ClO) 2 pretreatment and flocculation with PFS or PAC. Ca(ClO) 2 pretreatment also effectively inactivated fecal bacteria. The mechanisms of Ca(ClO) 2 pretreatment enhancing SS flocculation removal were further elucidated. The SS removal was the action of ClO - and Ca 2+ together. The function of ClO - was to break down suspended particles, change the surface, and decrease the absolute Zeta potential, while the function of Ca 2+ was to form precipitation. This result indicates that Ca(ClO) 2 pretreatment can effectively enhance the SS flocculation removal of anaerobic digested liquid., Competing Interests: Declaration of competing interest Our all the authors declare that there are no potential competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Activators affect the physical and chemical properties of carbon products. However, the effects of different activation mechanisms and pyrolysis conditions on the properties of carbon products still need to be explored. In this study, we obtained a new biochar by impregnation of reed powder with an alkali metal salt (CaCl 2 ) under a specific pyrolysis procedure and pyrolysis conditions. Impregnation by CaCl 2 can reduce the activation energy of the biomass while capturing and immobilizing oxygenated organic matter during pyrolysis. The new biochar has a high adsorption capacity of organic matters, for example Bisphenol A (BPA). The adsorption results showed that the modified biochar demonstrated a 364.5 % improvement in the adsorption capacity compared to the original biochar. The final performance enhancement was correlated with the confinement conditions of the environment and the procedure of pyrolysis. These procedures ultimately changed the pore distribution, functional group type, aromaticity, and degree of defects of the modified biochar. This study is important to screen synthetic pathways for identifying compounds with excellent adsorption effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)