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<xbrli:xbrl xmlns:in-capmkt="https://www.sebi.gov.in/xbrl/2023-05-31/in-capmkt" xmlns:in-capmkt-ent="https://www.sebi.gov.in/xbrl/Prior_Intimation_Of_Board_Meeting/2023-05-31/in-capmkt/in-capmkt-ent" xmlns:in-capmkt-roles="https://www.sebi.gov.in/xbrl/Prior_Intimation_Of_Board_Meeting/2023-05-31/in-capmkt-roles" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:in-capmkt-type="https://www.sebi.gov.in/xbrl/2023-05-31/in-capmkt-types" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:net="http://www.xbrl.org/2009/role/net" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:iso4217="http://www.xbrl.org/2003/iso4217" xmlns:negated="http://www.xbrl.org/2009/role/negated" xmlns:xbrldi="http://xbrl.org/2006/xbrldi" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xl="http://www.xbrl.org/2003/XLink"><link:schemaRef xlink:type="simple" xlink:href="in-capmkt-ent-2023-05-31.xsd"/><xbrli:context id="MainI"><xbrli:entity><xbrli:identifier scheme="https://www.sebi.gov.in/in-capmkt/NSESymbol">PCCL</xbrli:identifier></xbrli:entity><xbrli:period><xbrli:instant>2026-11-02</xbrli:instant></xbrli:period></xbrli:context><xbrli:context id="MainD"><xbrli:entity><xbrli:identifier scheme="https://www.sebi.gov.in/in-capmkt/NSESymbol">PCCL</xbrli:identifier></xbrli:entity><xbrli:period><xbrli:startDate>2026-11-02</xbrli:startDate><xbrli:endDate>2026-11-02</xbrli:endDate></xbrli:period></xbrli:context><xbrli:unit id="pure"><xbrli:measure>xbrli:pure</xbrli:measure></xbrli:unit><in-capmkt:NSESymbol contextRef="MainI">PCCL</in-capmkt:NSESymbol><in-capmkt:NameOfTheCompany contextRef="MainI">PETRO CARBON AND CHEMICALS LIMITED</in-capmkt:NameOfTheCompany><in-capmkt:WhetherCompanyIsSME contextRef="MainD">true</in-capmkt:WhetherCompanyIsSME><in-capmkt:ISIN contextRef="MainI">INE998U01015</in-capmkt:ISIN><in-capmkt:TypeOfMeeting contextRef="MainI">Board Meeting</in-capmkt:TypeOfMeeting><in-capmkt:TypeOfIntimation contextRef="MainD">New</in-capmkt:TypeOfIntimation><in-capmkt:DateOfProposedMeeting contextRef="MainD">2026-11-05</in-capmkt:DateOfProposedMeeting><in-capmkt:WhetherTradingWindowIsClosed contextRef="MainD">true</in-capmkt:WhetherTradingWindowIsClosed><in-capmkt:DateOfStartOfTradingWindowClosure contextRef="MainI">2026-10-01</in-capmkt:DateOfStartOfTradingWindowClosure><in-capmkt:DetailsOfDateOfEndOfTradingWindowClosure contextRef="MainI">Trading Window for dealing in the Securities of the Company will be closed till 48 hours after the declaration of the Unaudited Financial Results of the Company for the half year ended 30th September, 2026.</in-capmkt:DetailsOfDateOfEndOfTradingWindowClosure><in-capmkt:DateOfReport contextRef="MainI">2026-11-02</in-capmkt:DateOfReport><in-capmkt:Agenda1 contextRef="MainD">Financial results</in-capmkt:Agenda1><in-capmkt:WhetherResultsAreAuditedOrUnaudited contextRef="MainD">Unaudited</in-capmkt:WhetherResultsAreAuditedOrUnaudited><in-capmkt:NatureOfReportStandaloneConsolidated contextRef="MainD">Standalone And Consolidated</in-capmkt:NatureOfReportStandaloneConsolidated><in-capmkt:ReportingPeriodType contextRef="MainD">Half Yearly</in-capmkt:ReportingPeriodType><in-capmkt:MonthOfPeriodEnded contextRef="MainD">September</in-capmkt:MonthOfPeriodEnded><in-capmkt:YearOfPeriodEnded contextRef="MainI" unitRef="pure" decimals="0">2026</in-capmkt:YearOfPeriodEnded></xbrli:xbrl>