title: [Mechanisms of UV photodegradation on performance of a subsequent biofilter treating gaseous chlorobenzene].
abstract: To provide insight into effects of UV pretreatment on a subsequent biofilters, the mechanisms of UV pretreatment on biofilter performance were further studied. Results showed that gaseous chlorobenzene UV photodegradation products resulted in a pH decrease from 6-8 to 4-7 in filter bed. Ozone produced by UV photodegradation changed the physical properties of biofilm by reducing biofilm thickness and oxidizing surface part of the extra-cellular polymer substance, which promoted the oxygen, nutrient and pollutant transfer to biofilm. The reduction of biofilm thickness further resulted in the improvement of filter bed's physical properties by providing a higher specific surface area of 880 m x m(-3) compared with the value of 784 m2 x m(-3) without UV pretreatment.
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. wangcan04@mails.tsinghua.edu.cn
authors.forename: Can
authors.initials: C
authors.lastname: Wang
authors.forename: Jin-Ying
authors.initials: JY
authors.lastname: Xi
authors.forename: Hong-Ying
authors.initials: HY
authors.lastname: Hu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yao
mesh_terms: D000393:Air Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D002722:Chlorobenzenes / Q000737:chemistry / Q000302:isolation & purification*; D005374:Filtration / Q000379:methods*; D005740:Gases; D010126:Ozone / Q000737:chemistry; D010777:Photochemistry / Q000379:methods*; D014466:Ultraviolet Rays; D055549:Volatile Organic Compounds / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000393:Air Pollutants; D002722:Chlorobenzenes; D005740:Gases; D055549:Volatile Organic Compounds; D010126:Ozone; C031294:chlorobenzene