Methods

Data collection and workflow of the analysis

This study was conducted by collecting and analyzing the data produced by peer-reviewed articles published between 2010 and 2020. All the articles referred to in the analysis can be accessed through the link provided at the end of the reference section. For collecting data for this analysis, the databases “Scopus,” “Web of Science,” and “Google Scholar” were searched with keywords such as “algal bio-oil,” “pyrolysis of algae,” and “bio-oil from algae.” For data quality purposes, criteria were used to select the studies included in this analysis. The criteria used are: bio-oil should be produced exclusively by pyrolysis; the pyrolysis process input should be algal biomass; bio-oil should not be produced by co-pyrolysis of algae and other biomass types; the pyrolysis reaction should not include the use of catalyst. Studies satisfying these criteria were shortlisted for data collection. The data regarding the algal biomass characteristics, pyrolysis process condition and produced bio-oil were extracted from tables, figures, and supplementary materials included in the manuscript. The software “graph reader” was used to extract the figures' data. Subsequently, the data were processed and organized to analyze the effect of predictor variables on the response variable. The data collected for the analysis was from various published literature, which explored a wide range of values among the predictor variables. Thus, it was expected that the results obtained from this analysis would help generalize the influence of predictor variables on the response variables. The methodology implemented for this analysis has been summarized in Figure 1.