In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization...In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization process to convert DFP into activated carbon(DFPAC).In order to accomplish this research,several approaches were employed to examine the elemental composition,surface properties,amorphous and crystalline nature,essential active group,and surface morphology of the DFPAC.The BrunauerEmmettTeller test demonstrated a mesoporous structure of the DFPAC has a high surface area of 756.3 m2g 1.The cationic dye Methylene Blue(MB)was used as a probe to assess the efficiency of DFPAC towards the removal of MB dye from aqueous solution.The effects of adsorption input factors(e.g.DFPAC dose(A:0.040.12 g L 1),pH(B:310),and temperature(C:3050℃))were investigated and optimized using statistical analysis(i.e.BoxBehnken design(BBD)).The adsorption kinetic model can be best categorized as the pseudofirst order(PFO).Whereas,the adsorption isotherm model can be best described by Langmuir model,with maximum adsorption capacity of DFPAC for MB dye was 195.2 mg g 1 at 50℃.The adsorption mechanism of MB by DFPAC surface was attributed to the electrostatic interaction,pp interaction,and Hbonding.Finally,the results support the ability of DFP to be a promising precursor for production of highly porous activated carbon suitable for removal of cationic dyes(e.g.MB).展开更多
From soil contamination and risk assessment perspectives,it is imperative to understand the ecological processes occurring in soils.Certain soil processes greatly affect chemical speciation of potentially toxic metals...From soil contamination and risk assessment perspectives,it is imperative to understand the ecological processes occurring in soils.Certain soil processes greatly affect chemical speciation of potentially toxic metals(PTMs),and thus also influence their biogeochemical activity.The current study analyzed chemical speciation of eight PTMs(Cd,Cr,Fe,Cu,Mn,Ni,Zn,and Pb)in upper and lower soil layers for 15 agronomic fields of Vehari-Pakistan using Visual Minteq software.The divalent forms of most PTMs(PTM^(2+))generally predominated in both soil layers(79.9%overall occurrence).However,chromium revealed a different pattern of chemical speciation(95.8%as CrOH^(+))compared to other PTMs.The mean percentage of all the PTMs2+was slightly higher for the lower soil layer(81.3%)than in the upper layer(78.4%),the trend being same for all the PTMs,except Cr.This higher PTMs^(2+)percentage in lower soil layers than upper layers was due to lower content of organic matter and other anions such as Cl^(−)and HCO_(3)_(−).The mean percentage ages of all the PTMs^(2+)was similar among all the 15 agronomic fields,which was confirmed by strong Pearson correlation values(R^(2)>0.95).The PCA graph grouped all the agronomic fields and PTM^(2+) closely,except Cr^(2+) and Cu^(2+).This grouping confirmed the similar chemical speciation of PTMs,except Cu and Cr in studied fields.展开更多
基金the Universiti Teknologi MARA,Institute of Research Management and Innovation(Institut Pengu-rusan Penyelidikan&Inovasi)for funding this project underLES-TARI grant(600-IRMI 5/3/LESTARI(037/2019)).The authors Zeid A.ALOthman and Mohammad Rizwan Khan are thankful to the Researchers Supporting Project(RSP-2020/138),King Saud University,Riyadh,Saudi Arabia.
文摘In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization process to convert DFP into activated carbon(DFPAC).In order to accomplish this research,several approaches were employed to examine the elemental composition,surface properties,amorphous and crystalline nature,essential active group,and surface morphology of the DFPAC.The BrunauerEmmettTeller test demonstrated a mesoporous structure of the DFPAC has a high surface area of 756.3 m2g 1.The cationic dye Methylene Blue(MB)was used as a probe to assess the efficiency of DFPAC towards the removal of MB dye from aqueous solution.The effects of adsorption input factors(e.g.DFPAC dose(A:0.040.12 g L 1),pH(B:310),and temperature(C:3050℃))were investigated and optimized using statistical analysis(i.e.BoxBehnken design(BBD)).The adsorption kinetic model can be best categorized as the pseudofirst order(PFO).Whereas,the adsorption isotherm model can be best described by Langmuir model,with maximum adsorption capacity of DFPAC for MB dye was 195.2 mg g 1 at 50℃.The adsorption mechanism of MB by DFPAC surface was attributed to the electrostatic interaction,pp interaction,and Hbonding.Finally,the results support the ability of DFP to be a promising precursor for production of highly porous activated carbon suitable for removal of cationic dyes(e.g.MB).
基金Dr.Shahid thanks HEC-Pakistan for NTPU-4423 projectsupported by the Distinguished Scientist Fellowship Program(DSFP)at King Saud University,Riyadh,Saudi Arabia.
文摘From soil contamination and risk assessment perspectives,it is imperative to understand the ecological processes occurring in soils.Certain soil processes greatly affect chemical speciation of potentially toxic metals(PTMs),and thus also influence their biogeochemical activity.The current study analyzed chemical speciation of eight PTMs(Cd,Cr,Fe,Cu,Mn,Ni,Zn,and Pb)in upper and lower soil layers for 15 agronomic fields of Vehari-Pakistan using Visual Minteq software.The divalent forms of most PTMs(PTM^(2+))generally predominated in both soil layers(79.9%overall occurrence).However,chromium revealed a different pattern of chemical speciation(95.8%as CrOH^(+))compared to other PTMs.The mean percentage of all the PTMs2+was slightly higher for the lower soil layer(81.3%)than in the upper layer(78.4%),the trend being same for all the PTMs,except Cr.This higher PTMs^(2+)percentage in lower soil layers than upper layers was due to lower content of organic matter and other anions such as Cl^(−)and HCO_(3)_(−).The mean percentage ages of all the PTMs^(2+)was similar among all the 15 agronomic fields,which was confirmed by strong Pearson correlation values(R^(2)>0.95).The PCA graph grouped all the agronomic fields and PTM^(2+) closely,except Cr^(2+) and Cu^(2+).This grouping confirmed the similar chemical speciation of PTMs,except Cu and Cr in studied fields.
