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<!-- Creation Date :2023-11-22T14:57:21.0300+00:00 -->
<!-- Copyright (c) 2023 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="cbt_OtherCertainItems" name="OtherCertainItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_PrepaidExpensesAndOtherCurrentAssetsAccountsPayableAndAccruedLiabilitiesAndOtherAssetsMember" name="PrepaidExpensesAndOtherCurrentAssetsAccountsPayableAndAccruedLiabilitiesAndOtherAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_RevolvingCreditFacilityEuroExpiresFiscalTwoThousandTwentySevenMember" name="RevolvingCreditFacilityEuroExpiresFiscalTwoThousandTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ParticipatingSecurities" name="ParticipatingSecurities" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_StandardPaymentTermForRevenue" name="StandardPaymentTermForRevenue" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_TwoThousandTwentyFourToTwoThousandThirtyMember" name="TwoThousandTwentyFourToTwoThousandThirtyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_GuaranteedPerOccurrenceForAllOtherMember" name="GuaranteedPerOccurrenceForAllOtherMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_BrazilIndirectTaxSettlementsMember" name="BrazilIndirectTaxSettlementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPerformanceBasedAdjustmentWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPerformanceBasedAdjustmentWeightedAverageExercisePrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_RevolvingCreditFacilityExpiresFiscalTwoThousandTwentySevenMember" name="RevolvingCreditFacilityExpiresFiscalTwoThousandTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_FairValueLiabilitiesLevel1ToLevel2TransferAmount" name="FairValueLiabilitiesLevel1ToLevel2TransferAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedAdjustmentInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedAdjustmentInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedAnnualDividendRate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedAnnualDividendRate" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_GainLossOnDivestiture" name="GainLossOnDivestiture" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_CostOfSalesSellingAndAdministrativeExpenseAndResearchAndTechnicalExpenseMember" name="CostOfSalesSellingAndAdministrativeExpenseAndResearchAndTechnicalExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_EarningPerShareBasicAndDilutedAbstract" name="EarningPerShareBasicAndDilutedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_OperatingCashFlowsFromFinanceLeasesPayments" name="OperatingCashFlowsFromFinanceLeasesPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_CashAndOtherSecuritiesMember" name="CashAndOtherSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_FourPointZeroPercentageNotesDueTwoThousandAndTwentyNineMember" name="FourPointZeroPercentageNotesDueTwoThousandAndTwentyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ParentCompanyEndOfDayStockPrice" name="ParentCompanyEndOfDayStockPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_GoodwillAndIntangibleAssetsLineItems" name="GoodwillAndIntangibleAssetsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_OtherComprehensiveIncomeGainLossOnDerivativesArisingDuringPeriodBeforeTax" name="OtherComprehensiveIncomeGainLossOnDerivativesArisingDuringPeriodBeforeTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_AmortizationOfPriorUnrecognizedLossGain" name="AmortizationOfPriorUnrecognizedLossGain" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_ExciseTaxOnStockRepurchases" name="ExciseTaxOnStockRepurchases" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRateInterestCost" name="DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRateInterestCost" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_FairValueAssetsLevel2ToLevel1TransferAmount" name="FairValueAssetsLevel2ToLevel1TransferAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_ReclassificationFromAccumulatedOtherComprehensiveIncomeToRetainedEarningsTaxEffect" name="ReclassificationFromAccumulatedOtherComprehensiveIncomeToRetainedEarningsTaxEffect" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_IndefiniteCarryforwardMember" name="IndefiniteCarryforwardMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_AdditionalPreTaxLossOnSaleOfBusiness" name="AdditionalPreTaxLossOnSaleOfBusiness" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_EquipmentFailureMember" name="EquipmentFailureMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_NonUSGovernmentBondsMember" name="NonUSGovernmentBondsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_UnrecognizedTaxImpact" name="UnrecognizedTaxImpact" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_LeasesSupplementalBalanceSheetInformationTableTextBlock" name="LeasesSupplementalBalanceSheetInformationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_OperatingAndMaintenanceComponentMember" name="OperatingAndMaintenanceComponentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_PercentageOfVestingInFirstAnniversary" name="PercentageOfVestingInFirstAnniversary" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_RestructuringChargesBenefit" name="RestructuringChargesBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_PercentageOfExercisePriceEqualToMarketPriceOnDateOfGrant" name="PercentageOfExercisePriceEqualToMarketPriceOnDateOfGrant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_FivePercentageNotesDueTwoThousandAndThirtyTwoMember" name="FivePercentageNotesDueTwoThousandAndThirtyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ConcentrationRiskCreditRiskValue" name="ConcentrationRiskCreditRiskValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_FinanceLeaseCost" name="FinanceLeaseCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_LeaseLiabilityAbstract" name="LeaseLiabilityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_IncomeTaxReconciliationImpactOfCoronavirusAidReliefAndEconomicSecurityAct" name="IncomeTaxReconciliationImpactOfCoronavirusAidReliefAndEconomicSecurityAct" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_CurrentFederalAndStateTaxExpenseBenefit" name="CurrentFederalAndStateTaxExpenseBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_LesseeOperatingAndFinancingLeaseLiabilityMaturityTableTextBlock" name="LesseeOperatingAndFinancingLeaseLiabilityMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DividendsAndDividendEquivalentsToParticipatingSecurities" name="DividendsAndDividendEquivalentsToParticipatingSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_OneEquityPartnersMember" name="OneEquityPartnersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DefinedBenefitPlanSettlementsAndCurtailmentsPlanAssets" name="DefinedBenefitPlanSettlementsAndCurtailmentsPlanAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_FairValueAssetsLevel1ToLevel2TransferAmount" name="FairValueAssetsLevel1ToLevel2TransferAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_PercentageOfDefinedBenefitPlanEquitySecurities" name="PercentageOfDefinedBenefitPlanEquitySecurities" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DeferredTaxLiabilityRightOfUseAsset" name="DeferredTaxLiabilityRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_BusinessCombinationAcquisitionAndIntegrationRelatedCosts" name="BusinessCombinationAcquisitionAndIntegrationRelatedCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_RespiratorReservePeriod" name="RespiratorReservePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_PensionAndOtherPostretirementDefinedBenefitPlansAccountsPayableAndAccruedLiabilities" name="PensionAndOtherPostretirementDefinedBenefitPlansAccountsPayableAndAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_ChineseRenminbiDebtDueTwoThousandAndTwentyFourMember" name="ChineseRenminbiDebtDueTwoThousandAndTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedAdjustment" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsPerformanceBasedAdjustment" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DisclosureOfLeasesWeightedAverageRemainingLeaseTermAndDiscountRatesTableTextBlock" name="DisclosureOfLeasesWeightedAverageRemainingLeaseTermAndDiscountRatesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_NetSalesAndOtherOperatingRevenuesMember" name="NetSalesAndOtherOperatingRevenuesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ShenzhenSanshunNanoNewMaterialsCoLtdMember" name="ShenzhenSanshunNanoNewMaterialsCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_PercentageOfVestingInSecondAnniversary" name="PercentageOfVestingInSecondAnniversary" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_GuaranteedPerAccidentForUSWorkersCompensationMember" name="GuaranteedPerAccidentForUSWorkersCompensationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_InsuranceContractsMember" name="InsuranceContractsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ShareRepurchasesPolicyTextBlock" name="ShareRepurchasesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_NonUSCorporateBondsMember" name="NonUSCorporateBondsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_WeightedAverageMaturityOfOutstandingMediumTermNotes" name="WeightedAverageMaturityOfOutstandingMediumTermNotes" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DeferredFederalAndStateIncomeTaxExpenseBenefit" name="DeferredFederalAndStateIncomeTaxExpenseBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_UnrecognizedTaxBenefitsIncludedInConsolidatedFinancialStatement" name="UnrecognizedTaxBenefitsIncludedInConsolidatedFinancialStatement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_IndirectTaxSettlementCredits" name="IndirectTaxSettlementCredits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_ThreePointFourPercentageNotesDueTwoThousandAndTwentySixMember" name="ThreePointFourPercentageNotesDueTwoThousandAndTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_AccumulatedNetInvestmentHedgesGainLossExcludedFromEffectivenessTestingAndAmortizedToInterestExpenseMember" name="AccumulatedNetInvestmentHedgesGainLossExcludedFromEffectivenessTestingAndAmortizedToInterestExpenseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_FourPercentageNotesDueOnTwoThousandTwentyNineMember" name="FourPercentageNotesDueOnTwoThousandTwentyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ScheduleOfPerformanceSegmentTableTextBlock" name="ScheduleOfPerformanceSegmentTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_OperatingAndFinanceLeaseLiabilityNoncurrent" name="OperatingAndFinanceLeaseLiabilityNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_RetentionForMedicalCosts" name="RetentionForMedicalCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_RecentlyAdoptedAccountingStandardsPolicyTextBlock" name="RecentlyAdoptedAccountingStandardsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_PensionAndOtherPostretirementDefinedBenefitPlansOtherLiabilities" name="PensionAndOtherPostretirementDefinedBenefitPlansOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_MediumTermNotesDueOnTwoThousandAndTwentyEightMember" name="MediumTermNotesDueOnTwoThousandAndTwentyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_IncomeTaxReconciliationPurificationSolutionsBusinessDivestiture" name="IncomeTaxReconciliationPurificationSolutionsBusinessDivestiture" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_FivePointZeroPercentageNotesDueTwoThousandAndThirtyTwoMember" name="FivePointZeroPercentageNotesDueTwoThousandAndThirtyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_OtherForeignCountriesMember" name="OtherForeignCountriesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRateServiceCost" name="DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRateServiceCost" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_RespiratorReserve" name="RespiratorReserve" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_SupplementalRetirementSavingsPlanAggregateValueOfAccountsShares" name="SupplementalRetirementSavingsPlanAggregateValueOfAccountsShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_AccumulatedDefinedBenefitPlansAdjustmentNetSettlementAndCurtailmentLossGainMember" name="AccumulatedDefinedBenefitPlansAdjustmentNetSettlementAndCurtailmentLossGainMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_UnallocatedCorporateCosts" name="UnallocatedCorporateCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_SellingAndAdministrativeExpensesMember" name="SellingAndAdministrativeExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromNetInvestmentHedgesNetOfTax" name="AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromNetInvestmentHedgesNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_UKPlansMember" name="UKPlansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_FairValueLiabilitiesLevel2ToLevel1TransferAmount" name="FairValueLiabilitiesLevel2ToLevel1TransferAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_DivestitureRelatedCharges" name="DivestitureRelatedCharges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_IncomeTaxCreditRecovery" name="IncomeTaxCreditRecovery" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_ReservedForEnvironmentalMatters" name="ReservedForEnvironmentalMatters" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_AlternativeInvestmentsMember" name="AlternativeInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_GoodwillAndIntangibleAssetsTable" name="GoodwillAndIntangibleAssetsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_TokaiCarbonRegisteredCapitalMember" name="TokaiCarbonRegisteredCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_GuaranteedPerAccidentForAutoMember" name="GuaranteedPerAccidentForAutoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_InvestmentFundsMember" name="InvestmentFundsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DerivativeNotionalAmountLowerBuyingHigherSellingOfForeignExchange" name="DerivativeNotionalAmountLowerBuyingHigherSellingOfForeignExchange" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_SignificantTaxAttributesAndDatesOfExpirationLineItems" name="SignificantTaxAttributesAndDatesOfExpirationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_LegalEnvironmentalMattersAndReserves" name="LegalEnvironmentalMattersAndReserves" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_PercentageOfDefinedBenefitPlanRealEstate" name="PercentageOfDefinedBenefitPlanRealEstate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_OtherProductsAndServicesMember" name="OtherProductsAndServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_AmountExcludedFromEarningsBeforeInterestAndTax" name="AmountExcludedFromEarningsBeforeInterestAndTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_OtherComprehensiveIncomeLossNetInvestmentHedgesGainLossExcludedFromEffectivenessTestingAndAmortizedToInterestExpenseNetOfTax" name="OtherComprehensiveIncomeLossNetInvestmentHedgesGainLossExcludedFromEffectivenessTestingAndAmortizedToInterestExpenseNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_FederalAndStateIncomeTaxExpenseBenefitContinuingOperations" name="FederalAndStateIncomeTaxExpenseBenefitContinuingOperations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_DerivativeInstrumentsFrequencyOfCashSettlements" name="DerivativeInstrumentsFrequencyOfCashSettlements" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_ReinforcementMaterialsMember" name="ReinforcementMaterialsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DefinedBenefitPlanOtherPlanAssets" name="DefinedBenefitPlanOtherPlanAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_AccumulatedDefinedBenefitPlansAdjustmentNetUnamortizedGainLossAndPriorServiceCostCreditMember" name="AccumulatedDefinedBenefitPlansAdjustmentNetUnamortizedGainLossAndPriorServiceCostCreditMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_IncomeLossFromEquityMethodInvestmentsNetOfTax" name="IncomeLossFromEquityMethodInvestmentsNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_TwoThousandSeventeenLongTermIncentivePlanMember" name="TwoThousandSeventeenLongTermIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_AdjustedEarningsLossAllocatedToParticipatingSecurities" name="AdjustedEarningsLossAllocatedToParticipatingSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_PercentageOfDefinedBenefitPlanDebtSecurities" name="PercentageOfDefinedBenefitPlanDebtSecurities" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_CabotMember" name="CabotMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_RespiratorLiabilitiesMember" name="RespiratorLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DirectInvestmentsMember" name="DirectInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_DebtInstrumentCovenantRatioOfConsolidatedTotalDebtToConsolidatedEBITDA" name="DebtInstrumentCovenantRatioOfConsolidatedTotalDebtToConsolidatedEBITDA" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_UnrecognizedTaxBenefitsOffsetAgainstDeferredTaxAssets" name="UnrecognizedTaxBenefitsOffsetAgainstDeferredTaxAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_ThreePointSevenPercentageNotesDueInTwoThousandAndTwentyTwoMember" name="ThreePointSevenPercentageNotesDueInTwoThousandAndTwentyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_PerformanceAdditivesMember" name="PerformanceAdditivesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPerformanceBasedAdjustmentWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPerformanceBasedAdjustmentWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodWeightedAverageGrantDateFairValue" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_ChargesOnSaleOfNotesReceivables" name="ChargesOnSaleOfNotesReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_LesseeOperatingAndFinanceLeasesTextBlock" name="LesseeOperatingAndFinanceLeasesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_GainLossOnSaleOfLand" name="GainLossOnSaleOfLand" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_SpecialtyFluidsMember" name="SpecialtyFluidsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_USCorporateBondsMember" name="USCorporateBondsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_PreTaxLossOnSaleOfBusiness" name="PreTaxLossOnSaleOfBusiness" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_CurrencyDevaluationLoss" name="CurrencyDevaluationLoss" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_IncomeTaxBenefitFromTaxLossRelatedToDivestiture" name="IncomeTaxBenefitFromTaxLossRelatedToDivestiture" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_TokaiCarbonGroupTianjinCoMember" name="TokaiCarbonGroupTianjinCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_LineOfCreditCapAmountUsedToCalculateNetDebt" name="LineOfCreditCapAmountUsedToCalculateNetDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_PurificationSolutionsMember" name="PurificationSolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_NonCashIncomeTaxExpenseBenefit" name="NonCashIncomeTaxExpenseBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_EquityAffiliateInvestmentsMember" name="EquityAffiliateInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_ExpendituresForAdditionsToLongLivedAssets" name="ExpendituresForAdditionsToLongLivedAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_FixedRateDebtMember" name="FixedRateDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_LineOfCreditFacilityWeightedAverageInterestRate" name="LineOfCreditFacilityWeightedAverageInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="cbt_EnvironmentalMattersMember" name="EnvironmentalMattersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_PerformanceChemicalsMember" name="PerformanceChemicalsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_UndistributedLossEarningsAllocatedToCommonShareholders" name="UndistributedLossEarningsAllocatedToCommonShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_EmployeeBenefitPlanSettlementAndOtherCharges" name="EmployeeBenefitPlanSettlementAndOtherCharges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_DefinedBenefitPlanExpensesOnPlanAssets" name="DefinedBenefitPlanExpensesOnPlanAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="cbt_FormulatedSolutionsMember" name="FormulatedSolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_InsuranceRecoveryAbstract" name="InsuranceRecoveryAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="cbt_UndistributedLossEarningsAllocatedToParticipatingShareholders" name="UndistributedLossEarningsAllocatedToParticipatingShareholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_NumberOfBusinessActivity" name="NumberOfBusinessActivity" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="cbt_DefinedBenefitPlanContributionsByPlanParticipantsChangeInPlanAssets" name="DefinedBenefitPlanContributionsByPlanParticipantsChangeInPlanAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="cbt_ResearchAndTechnicalExpensesMember" name="ResearchAndTechnicalExpensesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
