Dealing with the current defaults of environmental toxicity, heating, waste management, and economic crises, exploration of novel non-edible, toxic, and waste feedstock for renewable biodiesel synthesis is the need of the hour. The present study is concerned with Buxus papillosa with seeds oil concentration (45% w/w), a promising biodiesel feedstock encountering environmental defaults and waste management; in addition, this research performed simulation based-response surface methodology (RSM) for Buxus papillosa bio-diesel. Synthesis and application of novel Phyto-nanocatalyst bimetallic oxide with Buxus papillosa fruit capsule aqueous extract was advantageous during transesterification. Characterization of sodium/potassium oxide Phyto-nanocatalyst confirmed 23.5 nm nano-size and enhanced catalytic activity. Other characterizing tools are FTIR, DRS, XRD, Zeta potential, SEM, and EDX. Methyl ester formation was authenticated by FTIR, GC-MS, and NMR. A maximum 97% yield was obtained at optimized conditions i.e., methanol ratio to oil (8:1), catalyst amount (0.37 wt%), reaction duration (180 min), and temperature of 80 °C. The reusability of novel sodium/potassium oxide was checked for six reactions. Buxus papillosa fuel properties were within the international restrictions of fuel. The sulphur content of 0.00090% signified the environmental remedial nature of Buxus papillosa methyl esters and it is a highly recommendable species for biodiesel production at large scale due to a t huge number of seeds production and vast distribution.

Department of Chemical Engineering COMSATS University Islamabad Lahore Campus 54000 Lahore Punjab Pakistan; School of Engineering Lebanese American University Byblos Lebanon; Sustainable Process Integration Laboratory SPIL NETME Centra Faculty of Mechanical Engineering Brno University of Technology VUT Brno Technická 2896 2 Brno 616 00 Czech Republic

Department of Clinical Nutrition Faculty of Applied Medical Sciences Umm Al Qura University Makkah Kingdom of Saudi Arabia

Department of Plant Sciences Quaid i Azam University Islamabad 45320 Pakistan

Faculty of Sciences Department of Botany PMAS Arid Agriculture University Rawalpindi Pakistan

School of Civil and Environmental Engineering The University of New South Wales Sydney NSW 2052 Australia

Tecnologico de Monterrey Escuela de Ingenieríay Ciencias Puebla Mexico; Faculty of Health and Life Sciences INTI International University 71800 Nilai Negeri Sembilan Malaysia

University of Gastronomic Sciences Piazza Vittorio Emanuele 2 9 12042 Pollenzo Italy; Department of Medical Analysis Tishk International University Erbil 44001 Kurdistan Iraq

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