Pyrolyzed fabrication of N/P co-doped biochars from (NH4)3PO4-pretreated coffee shells and appraisement for remedying aqueous Cr(VI) contaminants

Remediation of hexavalent chromium and pharmaceuticals from aquatic environments by employing an oxygen-doped porous carbon adsorbent and its antifungal activity

“…14 Specifically, biochar produced during the pyrolysis of agricultural by-products is of serious importance for employment as a low-cost adsorbent for the adsorption of a wide range of industrial contaminants from water. 15,16 In previously reported literature, various adsorbent materials (including aminefunctionalized magnetic biochar, 17 polyaniline -TiO 2 hydrate, 18 nitrogen-doped porous carbon, 19 heteroatom-doped carbon materials, 16,[20][21][22] coffee shells, 6 Pisum sativum pods, 23 rubber sludge-derived activated carbon, 24 acid-modified waste fungal biomass, 25 and natural peach gum polysaccharide based adsorbents 26,27 ) were employed for the effective remediation of hexavalent chromium from the aquatic environment.…”

Cu-Based Catalysts Supported on H3PO4-Activated Coffee Biochar for Selective Reduction of Nitroaromatics

“…The peak at 398.7 eV can be ascribed to the sp 2 -hybridized N atom (C�N−C, pyridinic N), while the peak at 400.4 eV can be indexed as graphitic N (N-(C) 3 ). The peak at 401.5 eV should belong to quaternary N. 40 As shown in Figure S4e, the Cu 2p 3/2 peak at 933.6 eV, Cu 2p 1/2 peak at 953.5 eV, and shake-up satellite peaks can be assigned to Cu 2+ species. 41,42 The presence of oxidation states of Cu over Cu/BCR-600 could be attributed to the surface oxidation of Cu NPs during the XPS test.…”

“…The peak at 133.2 eV is ascribed to C−P, while the peak at 134.3 eV could be indexed as P� O/P−O. 40 As shown in Figure 3f, the peaks at 931.6 and 951.5 eV are consistent with Cu 2p 3/2 and Cu 2p 1/2 of Cu 0 , 46,47 respectively, indicating that Cu 0 acts as the active site in nitroaromatics reduction for Cu/PBCR-600. Noteworthily, no other peaks corresponding to oxidized states of Cu could be detected over Cu/PBCR-600, implying that the Cu 0 supported on PBCR-600 is immune to oxygen in the air, which may be attributed to the strong interaction between Cu 0 and PBCR-600.…”

“…39 Figure S4c shows the O 1s XPS spectra; the peaks at 531.5 and 532.9 eV could originate from C�O/N�C−O and C−O bonds, respectively. 40 Figure S4d depicts the N 1s XPS spectra, which can be fitted to three peaks. The peak at 398.7 eV can be ascribed to the sp 2 -hybridized N atom (C�N−C, pyridinic N), while the peak at 400.4 eV can be indexed as graphitic N (N-(C) 3 ).…”

Resource utilization of agricultural residues: one-step preparation of biochar derived from Pennisetum giganteum for efficiently removing chromium from water in a wide pH range

“…T The common activators are ZnCl2, KOH, Na2CO3, H3PO4, etc. Yang et al (Li et al 2020). Researchers (Yu et al 2020) used FeCl3 and ZnCl2 modified corn straw to remove Cr (VI), and its adsorption capacity could reach 138.89 mg g-1, but the solution environment had to be adjusted to pH = 2 .…”