TY - JOUR
T1 - Shiitake spent mushroom substrate as a sustainable feedstock for developing highly efficient nitrogen-doped biochars for treatment of dye-contaminated water
AU - Grimm, Alejandro
AU - dos Reis, Glaydson Simões
AU - Khokarale, Santosh Govind
AU - Ekman, Simon
AU - Lima, Eder C.
AU - Xiong, Shaojun
AU - Hultberg, Malin
N1 - Publisher Copyright:
© 2023 The Authors
PY - 2023/12
Y1 - 2023/12
N2 - Edible white-rot mushrooms are organisms that are cultivated at an industrial scale using wood-based substrates. The mushroom industry has an estimated annual production of 34 Mt of edible mushrooms, and approximately 70 wt% of the substrate is left as waste known as spent mushroom substrate (SMS). The huge volumes of SMS generated by mushroom farms hinder proper recycling, meaning that combustion or open-field burning are common disposal practices. This paper shows a concept that could help reduce the environmental impact of the mushroom industry. SMS from the cultivation of shiitake mushroom was used as a carbon precursor for the production of nitrogen-doped activated biochar that was used to remove reactive orange-16 (RO-16) azo dye from water, as well as contaminants from two synthetic effluents and real sewage water. Melamine was used as a nitrogen dopant and phosphoric acid as an activating agent. Samples without the addition of melamine were used for comparison. The doping/impregnation process was carried out in one-step, followed by pyrolysis at 700 and 900 °C for 1 h. BET, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used for the characterization of the biochars. The specific surface area of the doped samples was slightly lower, i.e., 1011 m2/g (SMS-700 °C), 810 m2/g (SMS-700 °C + N), 1095 m2/g (SMS-900 °C), and 943 m2/g (SMS-900 °C + N). Raman spectroscopic analysis showed that the N-doped biochars had more defective carbon structures than the non-doped ones. XPS analysis showed that doping with melamine led to the formation of N-functionalities on the surface of the biochar particles. The kinetics of adsorption were well represented by the Avrami model. The adsorption isotherms were well-fitted by the Liu model. The maximum adsorption capacities (qmax) of RO-16 were much higher for the N-doped biochars, i.e., 120 mg/g (SMS-700 °C), 216 mg/g (SMS-700 °C + N), 168 mg/g (SMS-900 °C), and 393 mg/g (SMS-900 °C + N). N-doped biochar samples were more effective for the removal of contaminants from synthetic effluents and sewage water. N-doped biochar produced at 900 °C showed good recyclability. This work concludes that SMS is a valuable waste that could be used for the production of activated carbon and that N-doping helped to improve the adsorption performance to a great extent.
AB - Edible white-rot mushrooms are organisms that are cultivated at an industrial scale using wood-based substrates. The mushroom industry has an estimated annual production of 34 Mt of edible mushrooms, and approximately 70 wt% of the substrate is left as waste known as spent mushroom substrate (SMS). The huge volumes of SMS generated by mushroom farms hinder proper recycling, meaning that combustion or open-field burning are common disposal practices. This paper shows a concept that could help reduce the environmental impact of the mushroom industry. SMS from the cultivation of shiitake mushroom was used as a carbon precursor for the production of nitrogen-doped activated biochar that was used to remove reactive orange-16 (RO-16) azo dye from water, as well as contaminants from two synthetic effluents and real sewage water. Melamine was used as a nitrogen dopant and phosphoric acid as an activating agent. Samples without the addition of melamine were used for comparison. The doping/impregnation process was carried out in one-step, followed by pyrolysis at 700 and 900 °C for 1 h. BET, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used for the characterization of the biochars. The specific surface area of the doped samples was slightly lower, i.e., 1011 m2/g (SMS-700 °C), 810 m2/g (SMS-700 °C + N), 1095 m2/g (SMS-900 °C), and 943 m2/g (SMS-900 °C + N). Raman spectroscopic analysis showed that the N-doped biochars had more defective carbon structures than the non-doped ones. XPS analysis showed that doping with melamine led to the formation of N-functionalities on the surface of the biochar particles. The kinetics of adsorption were well represented by the Avrami model. The adsorption isotherms were well-fitted by the Liu model. The maximum adsorption capacities (qmax) of RO-16 were much higher for the N-doped biochars, i.e., 120 mg/g (SMS-700 °C), 216 mg/g (SMS-700 °C + N), 168 mg/g (SMS-900 °C), and 393 mg/g (SMS-900 °C + N). N-doped biochar samples were more effective for the removal of contaminants from synthetic effluents and sewage water. N-doped biochar produced at 900 °C showed good recyclability. This work concludes that SMS is a valuable waste that could be used for the production of activated carbon and that N-doping helped to improve the adsorption performance to a great extent.
KW - Doped biochars
KW - Effluents
KW - Nitrogen doping
KW - Phosphoric acid activation
KW - Reactive orange-16 adsorption
KW - Spent mushroom substrate
UR - http://www.scopus.com/inward/record.url?scp=85174464226&partnerID=8YFLogxK
U2 - 10.1016/j.jwpe.2023.104435
DO - 10.1016/j.jwpe.2023.104435
M3 - Article
SN - 2214-7144
VL - 56
JO - Journal of Water Process Engineering
JF - Journal of Water Process Engineering
M1 - 104435
ER -