{"id":"https://openalex.org/W7223233449","doi":"https://doi.org/10.1021/acsomega.6c07244","title":"Carbon Dioxide Flushing and Zero-Valent Iron Addition during Anaerobic Digestion: Biogas Upgrading Does Not Necessarily Indicate Enhanced Biodegradation","display_name":"Carbon Dioxide Flushing and Zero-Valent Iron Addition during Anaerobic Digestion: Biogas Upgrading Does Not Necessarily Indicate Enhanced Biodegradation","publication_year":2026,"publication_date":"2026-10-22","ids":{"openalex":"https://openalex.org/W7223233449","doi":"https://doi.org/10.1021/acsomega.6c07244"},"language":"en","primary_location":{"id":"doi:10.1021/acsomega.6c07244","doi":"https://doi.org/10.1021/acsomega.6c07244","is_oa":true,"landing_page_url":"https://doi.org/10.1021/acsomega.6c07244","pdf_url":"https://pubs.acs.org/acsodf/article-pdf/doi/10.1021/acsomega.6c07244/68956449/acsomega.6c07244.pdf","source":{"id":"https://openalex.org/S4210239500","display_name":"ACS Omega","issn_l":"2470-1343","issn":["2470-1343"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["cwts-core","doaj","dongbi-c","jufo-1","ki-jl-1","norway-1","oarl","poland-70","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320006","host_organization_name":"American Chemical Society","host_organization_lineage":["https://openalex.org/P4310320006"],"host_organization_lineage_names":["American Chemical Society"],"type":"journal"},"license":"cc-by-nc-nd","license_id":"https://openalex.org/licenses/cc-by-nc-nd","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"ACS Omega","raw_type":"journal-article"},"volume":null,"type":"article","indexed_in":["crossref","doaj"],"open_access":{"is_oa":true,"oa_status":"gold","oa_url":"https://pubs.acs.org/acsodf/article-pdf/doi/10.1021/acsomega.6c07244/68956449/acsomega.6c07244.pdf","any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5116367971","display_name":"Panagiota Karachaliou","orcid":"https://orcid.org/0009-0003-4203-8920","observed_orcids":["https://orcid.org/0009-0003-4203-8920"]},"institutions":[{"id":"https://openalex.org/I163151358","display_name":"Cyprus University of Technology","ror":"https://ror.org/05qt8tf94","country_code":"CY","type":"education","lineage":["https://openalex.org/I163151358"]}],"countries":["CY"],"is_corresponding":false,"raw_author_name":"Panagiota Karachaliou","raw_affiliation_strings":["Cyprus University of Technology , , Anexartisias 57 Str. , ,"],"raw_orcid":"https://orcid.org/0009-0003-4203-8920","affiliations":[{"raw_affiliation_string":"Cyprus University of Technology , , Anexartisias 57 Str. , ,","institution_ids":["https://openalex.org/I163151358"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5126947768","display_name":"Andreas Laos","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I163151358","display_name":"Cyprus University of Technology","ror":"https://ror.org/05qt8tf94","country_code":"CY","type":"education","lineage":["https://openalex.org/I163151358"]}],"countries":["CY"],"is_corresponding":false,"raw_author_name":"Andreas Laos","raw_affiliation_strings":["Cyprus University of Technology , , Anexartisias 57 Str. , ,"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Cyprus University of Technology , , Anexartisias 57 Str. , ,","institution_ids":["https://openalex.org/I163151358"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5003065278","display_name":"Ioannis Vyrides","orcid":"https://orcid.org/0000-0001-8316-4577","observed_orcids":["https://orcid.org/0000-0001-8316-4577"]},"institutions":[{"id":"https://openalex.org/I163151358","display_name":"Cyprus University of Technology","ror":"https://ror.org/05qt8tf94","country_code":"CY","type":"education","lineage":["https://openalex.org/I163151358"]}],"countries":["CY"],"is_corresponding":true,"raw_author_name":"Ioannis Vyrides","raw_affiliation_strings":["Cyprus University of Technology , , Anexartisias 57 Str. , ,"],"raw_orcid":"https://orcid.org/0000-0001-8316-4577","affiliations":[{"raw_affiliation_string":"Cyprus University of Technology , , Anexartisias 57 Str. , ,","institution_ids":["https://openalex.org/I163151358"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":["https://openalex.org/A5003065278"],"corresponding_institution_ids":["https://openalex.org/I163151358"],"apc_list":{"value":1935,"currency":"USD","value_usd":1935},"apc_paid":{"value":1935,"currency":"USD","value_usd":1935},"fwci":0.0,"has_fulltext":true,"cited_by_count":0,"citation_normalized_percentile":{"value":0.77837459,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":null,"biblio":{"volume":"11","issue":"43","first_page":"67022","last_page":"67033"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10284","display_name":"Anaerobic Digestion and Biogas Production","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/2215","display_name":"Building and Construction"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10284","display_name":"Anaerobic Digestion and Biogas Production","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/2215","display_name":"Building and Construction"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11952","display_name":"Landfill Environmental Impact Studies","score":9.999999747378752e-05,"subfield":{"id":"https://openalex.org/subfields/2311","display_name":"Waste Management and Disposal"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11231","display_name":"Microbial Fuel Cells and Bioremediation","score":9.999999747378752e-05,"subfield":{"id":"https://openalex.org/subfields/2305","display_name":"Environmental Engineering"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/zero-valent-iron","display_name":"zero-valent iron","score":0.9950000047683716},{"id":"https://openalex.org/keywords/anaerobic-digestion","display_name":"anaerobic digestion","score":0.9959999918937683},{"id":"https://openalex.org/keywords/biogas-upgrading","display_name":"biogas upgrading","score":0.9309999942779541},{"id":"https://openalex.org/keywords/methane-production","display_name":"methane production","score":0.8840000033378601},{"id":"https://openalex.org/keywords/piggery-waste","display_name":"piggery waste","score":0.9670000076293945},{"id":"https://openalex.org/keywords/hydrogenotrophic-methanogenesis","display_name":"hydrogenotrophic methanogenesis","score":0.8510000109672546},{"id":"https://openalex.org/keywords/acetoclastic-methanogenesis","display_name":"acetoclastic methanogenesis","score":0.9929999709129333},{"id":"https://openalex.org/keywords/organic-matter-transformation","display_name":"organic matter transformation","score":0.6949999928474426},{"id":"https://openalex.org/keywords/process-stability","display_name":"process stability","score":0.6019999980926514},{"id":"https://openalex.org/keywords/ph-control","display_name":"pH control","score":0.492000013589859},{"id":"https://openalex.org/keywords/bicarbonate","display_name":"bicarbonate","score":0.578000009059906},{"id":"https://openalex.org/keywords/thermodynamic-analysis","display_name":"thermodynamic analysis","score":0.531000018119812}],"concepts":[{"id":"https://openalex.org/C2778589620","wikidata":"https://www.wikidata.org/wiki/Q22275999","display_name":"Methanogenesis","level":3,"score":0.9085000157356262},{"id":"https://openalex.org/C516920438","wikidata":"https://www.wikidata.org/wiki/Q37129","display_name":"Methane","level":2,"score":0.8181999921798706},{"id":"https://openalex.org/C185592680","wikidata":"https://www.wikidata.org/wiki/Q2329","display_name":"Chemistry","level":0,"score":0.7731000185012817},{"id":"https://openalex.org/C75212476","wikidata":"https://www.wikidata.org/wiki/Q171076","display_name":"Biogas","level":2,"score":0.7299000024795532},{"id":"https://openalex.org/C48743137","wikidata":"https://www.wikidata.org/wiki/Q1783121","display_name":"Organic matter","level":2,"score":0.6680999994277954},{"id":"https://openalex.org/C2778520758","wikidata":"https://www.wikidata.org/wiki/Q3443277","display_name":"Flushing","level":2,"score":0.6395999789237976},{"id":"https://openalex.org/C530467964","wikidata":"https://www.wikidata.org/wiki/Q1997","display_name":"Carbon dioxide","level":2,"score":0.5911999940872192},{"id":"https://openalex.org/C2781112554","wikidata":"https://www.wikidata.org/wiki/Q409202","display_name":"Bicarbonate","level":2,"score":0.4984999895095825},{"id":"https://openalex.org/C499616599","wikidata":"https://www.wikidata.org/wiki/Q555853","display_name":"Anaerobic digestion","level":3,"score":0.4799000024795532},{"id":"https://openalex.org/C5140985","wikidata":"https://www.wikidata.org/wiki/Q483866","display_name":"Anaerobic exercise","level":2,"score":0.474700003862381},{"id":"https://openalex.org/C48843007","wikidata":"https://www.wikidata.org/wiki/Q181713","display_name":"Anaerobic respiration","level":3,"score":0.4359000027179718},{"id":"https://openalex.org/C528095902","wikidata":"https://www.wikidata.org/wiki/Q2283886","display_name":"Pulp and paper industry","level":1,"score":0.42559999227523804},{"id":"https://openalex.org/C107872376","wikidata":"https://www.wikidata.org/wiki/Q321355","display_name":"Environmental chemistry","level":1,"score":0.39969998598098755},{"id":"https://openalex.org/C157021035","wikidata":"https://www.wikidata.org/wiki/Q696715","display_name":"Biodegradation","level":2,"score":0.39899998903274536},{"id":"https://openalex.org/C13080248","wikidata":"https://www.wikidata.org/wiki/Q864214","display_name":"Biodegradable waste","level":2,"score":0.36070001125335693},{"id":"https://openalex.org/C140205800","wikidata":"https://www.wikidata.org/wiki/Q5860","display_name":"Carbon fibers","level":3,"score":0.35760000348091125},{"id":"https://openalex.org/C168170006","wikidata":"https://www.wikidata.org/wiki/Q864699","display_name":"Bioreactor","level":2,"score":0.31709998846054077},{"id":"https://openalex.org/C548081761","wikidata":"https://www.wikidata.org/wiki/Q180388","display_name":"Waste management","level":1,"score":0.3165999948978424},{"id":"https://openalex.org/C104577883","wikidata":"https://www.wikidata.org/wiki/Q4065016","display_name":"Anaerobic oxidation of methane","level":3,"score":0.30140000581741333},{"id":"https://openalex.org/C512968161","wikidata":"https://www.wikidata.org/wiki/Q556","display_name":"Hydrogen","level":2,"score":0.28360000252723694},{"id":"https://openalex.org/C202189072","wikidata":"https://www.wikidata.org/wiki/Q1929999","display_name":"Hydrogen production","level":3,"score":0.27799999713897705},{"id":"https://openalex.org/C45812177","wikidata":"https://www.wikidata.org/wiki/Q432016","display_name":"Alkalinity","level":2,"score":0.2759000062942505}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1021/acsomega.6c07244","doi":"https://doi.org/10.1021/acsomega.6c07244","is_oa":true,"landing_page_url":"https://doi.org/10.1021/acsomega.6c07244","pdf_url":"https://pubs.acs.org/acsodf/article-pdf/doi/10.1021/acsomega.6c07244/68956449/acsomega.6c07244.pdf","source":{"id":"https://openalex.org/S4210239500","display_name":"ACS Omega","issn_l":"2470-1343","issn":["2470-1343"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["cwts-core","doaj","dongbi-c","jufo-1","ki-jl-1","norway-1","oarl","poland-70","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320006","host_organization_name":"American Chemical Society","host_organization_lineage":["https://openalex.org/P4310320006"],"host_organization_lineage_names":["American Chemical Society"],"type":"journal"},"license":"cc-by-nc-nd","license_id":"https://openalex.org/licenses/cc-by-nc-nd","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"ACS Omega","raw_type":"journal-article"}],"best_oa_location":{"id":"doi:10.1021/acsomega.6c07244","doi":"https://doi.org/10.1021/acsomega.6c07244","is_oa":true,"landing_page_url":"https://doi.org/10.1021/acsomega.6c07244","pdf_url":"https://pubs.acs.org/acsodf/article-pdf/doi/10.1021/acsomega.6c07244/68956449/acsomega.6c07244.pdf","source":{"id":"https://openalex.org/S4210239500","display_name":"ACS Omega","issn_l":"2470-1343","issn":["2470-1343"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["cwts-core","doaj","dongbi-c","jufo-1","ki-jl-1","norway-1","oarl","poland-70","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320006","host_organization_name":"American Chemical Society","host_organization_lineage":["https://openalex.org/P4310320006"],"host_organization_lineage_names":["American Chemical Society"],"type":"journal"},"license":"cc-by-nc-nd","license_id":"https://openalex.org/licenses/cc-by-nc-nd","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"ACS Omega","raw_type":"journal-article"},"sustainable_development_goals":[{"score":0.9786999821662903,"id":"https://metadata.un.org/sdg/13","display_name":"Climate action"},{"score":0.875,"id":"https://metadata.un.org/sdg/7","display_name":"Affordable and clean energy"},{"score":0.7811999917030334,"id":"https://metadata.un.org/sdg/12","display_name":"Responsible consumption and production"}],"study_designs":[],"awards":[],"funders":[{"id":"https://openalex.org/F4320330084","display_name":"Research and Innovation Foundation","ror":null}],"has_content":{"pdf":true,"grobid_xml":true},"content_urls":{"pdf":"https://content.openalex.org/works/W7223233449.pdf","grobid_xml":"https://content.openalex.org/works/W7223233449.grobid-xml"},"referenced_works_count":23,"referenced_works":["https://openalex.org/W1896333691","https://openalex.org/W2018075424","https://openalex.org/W2091913250","https://openalex.org/W2112951169","https://openalex.org/W2135794677","https://openalex.org/W2505276462","https://openalex.org/W2747431209","https://openalex.org/W2887700613","https://openalex.org/W2888820335","https://openalex.org/W3027675529","https://openalex.org/W3034395636","https://openalex.org/W3097243585","https://openalex.org/W3153871484","https://openalex.org/W4284886569","https://openalex.org/W4317038923","https://openalex.org/W4320170290","https://openalex.org/W4384207917","https://openalex.org/W4387842243","https://openalex.org/W4401922852","https://openalex.org/W4404011662","https://openalex.org/W4407821330","https://openalex.org/W4409644838","https://openalex.org/W7125487291"],"related_works":["https://openalex.org/W4391819692","https://openalex.org/W2985895162","https://openalex.org/W4409644838","https://openalex.org/W4407821330","https://openalex.org/W4413682278","https://openalex.org/W3206795926","https://openalex.org/W2761321743","https://openalex.org/W6889969159","https://openalex.org/W4313219468","https://openalex.org/W2742985973"],"abstract_inverted_index":{"Abstract":[0],"Carbon":[1],"dioxide":[2],"(CO2)":[3],"supplementation":[4,89],"and":[5,51,59,79,125,134,162,170,216],"zero-valent":[6],"iron":[7],"(ZVI)":[8],"addition":[9,53,121],"have":[10],"been":[11],"proposed":[12],"as":[13],"strategies":[14],"for":[15,39,213],"enhancing":[16],"methane":[17,55,68,92,99,132,135,225],"production":[18,100,133,226],"during":[19],"anaerobic":[20,27],"digestion.":[21],"In":[22],"this":[23],"study,":[24],"eight":[25],"semibatch":[26],"digesters":[28],"(four":[29],"treatments":[30],"operated":[31,38],"in":[32,95,188,227],"duplicate)":[33],"treating":[34],"piggery":[35],"waste":[36],"were":[37],"100":[40],"days":[41],"to":[42,72,176],"evaluate":[43],"the":[44,96,137,146,158,177,181,189,209],"combined":[45,102],"effects":[46],"of":[47],"CO2":[48,77,85,88,110,154],"flushing":[49,78,111],"strategy":[50],"ZVI":[52,120,152],"on":[54],"production,":[56],"process":[57],"stability,":[58],"organic":[60,142,183,235],"matter":[61,143,184,236],"conversion.":[62],"ZVI-amended":[63,138,228],"reactors":[64,139,148,156,192],"achieved":[65,187],"substantially":[66],"higher":[67,224],"contents,":[69,136],"reaching":[70],"up":[71],"98%":[73],"CH4":[74,82],"under":[75,83,116],"single":[76],"approximately":[80],"90%":[81],"periodic":[84],"flushing.":[86],"Periodic":[87],"promoted":[90],"sustained":[91],"generation,":[93],"resulting":[94],"highest":[97,159],"cumulative":[98],"when":[101],"with":[103],"ZVI.":[104,150,194],"Preliminary":[105],"experiments":[106],"further":[107,197],"showed":[108,157],"that":[109,199,223],"can":[112],"effectively":[113],"reduce":[114],"pH":[115],"alkaline":[117],"conditions,":[118],"whereas":[119,180],"enhances":[122],"hydrogen":[123],"generation":[124],"counteracts":[126],"excessive":[127],"acidification.":[128],"Despite":[129],"their":[130],"superior":[131],"exhibited":[140],"lower":[141],"conversion":[144],"than":[145],"corresponding":[147],"without":[149,193],"The":[151],"+":[153],"once-flushed":[155],"residual":[160],"TOC":[161],"soluble":[163],"COD":[164],"concentrations":[165,202],"(approximately":[166],"2104":[167],"mg":[168,172],"L\u20131":[169],"5129":[171],"L\u20131,":[173],"respectively)":[174],"due":[175],"high":[178],"pH,":[179],"greatest":[182],"removal":[185],"was":[186],"periodically":[190],"flushed":[191],"Thermodynamic":[195],"calculations":[196],"demonstrated":[198],"increasing":[200],"bicarbonate":[201],"selectively":[203],"favored":[204],"hydrogenotrophic":[205],"methanogenesis":[206,215],"while":[207],"reducing":[208],"thermodynamic":[210],"driving":[211],"force":[212],"acetoclastic":[214],"protein":[217],"(alanine)":[218],"biodegradation.":[219],"These":[220],"findings":[221],"indicate":[222],"systems":[229],"did":[230],"not":[231],"necessarily":[232],"reflect":[233],"greater":[234],"degradation.":[237]},"counts_by_year":[],"updated_date":"2026-11-04T10:54:05.112534","created_date":"2026-10-23T00:00:00"}