Research trends on phosphorus removal from wastewater: A review and bibliometric analysis from 2000 to 2022

The removal and recovery of phosphorus from wastewater is a crucial topic for environmental protection and resource utilization. This work provides a review of research advances in phosphorus removal and recovery from wastewater, based on a visual analysis of relevant literatures using bibliometric tools such as Citespace, VOSviewer, and Bibliometrix R-package. Literatures including 8973 publications from 2000 to 2022 were collected from the Web of Science database. The literatures were analyzed in terms of publication trends, disciplinary categories, journals, countries, institutions, and authors. Furthermore, detailed analysis of keywords was conducted on keyword co-occurrence, clustering, and bursting trends. Two distinct stages in the development of this field are observed with a rapid growth stage since 2013. The majority of publications can be categorized under the field of Ecology and Environment. The most productive journal is Water Science and Technology (668 papers, 7.45%), while Water Research demonstrates the highest average citation number per paper (68.39), emphasizing its significance as a platform for influential research. China is the leading country in terms of publication output (3355 papers, 37.39%), with active collaborations with other countries. The Chinese Academy of Sciences is leading in institutions. The top three authors are Peng, Yongzhen (110 papers), Van Loosdrecht, Mark C.M. (83 papers), and Nielsen, Per Halkjær (52 papers). Keyword clustering analysis reveals that "phosphorus removal", "nutrient removal", and "nitrogen removal" remain research hotspots. Furthermore, bursting keywords such as "aerobic denitrification", "fermentation", "anammox", and "electrocoagulation" gain increasing attention and may become new research focal points. Future research should focus on exploring innovative strategies that promote resource utilization, mitigate environmental pollution, and contribute to long-term sustainability in wastewater treatment.