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  <xs:element id="oec_LongTermDebtGrossCurrent" abstract="false" name="LongTermDebtGrossCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_LongtermDebtExcludingCurrentMaturitiesGross" abstract="false" name="LongtermDebtExcludingCurrentMaturitiesGross" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_WorkingCapitalLoanMember" abstract="true" name="WorkingCapitalLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_OrionEngineeredCarbonsGmbHMember" abstract="true" name="OrionEngineeredCarbonsGmbHMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_OrionEngineeredCarbonsLLCMember" abstract="true" name="OrionEngineeredCarbonsLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_OrionEngineeredCarbonsHuaibeiMember" abstract="true" name="OrionEngineeredCarbonsHuaibeiMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_RevolvingCreditFacilityTotalCommitmentMember" abstract="true" name="RevolvingCreditFacilityTotalCommitmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_RevolvingCreditFacilityAncillaryCreditFacilitiesMember" abstract="true" name="RevolvingCreditFacilityAncillaryCreditFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_UncommittedMember" abstract="true" name="UncommittedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_CommittedMember" abstract="true" name="CommittedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_ChinaWorkingCapitalLoansMember" abstract="true" name="ChinaWorkingCapitalLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_CounterpartyOneMember" abstract="true" name="CounterpartyOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_CounterpartyTwoMember" abstract="true" name="CounterpartyTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_NumberOfEmissionAllowanceCertificatesSold" abstract="false" name="NumberOfEmissionAllowanceCertificatesSold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="oec_ProceedsFromSaleOfEmissionsCertificate" abstract="false" name="ProceedsFromSaleOfEmissionsCertificate" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_EmissionsCertificatesRepurchaseObligationAmount" abstract="false" name="EmissionsCertificatesRepurchaseObligationAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_SecuritiesSoldUnderAgreementsToRepurchaseIncludingInterest" abstract="false" name="SecuritiesSoldUnderAgreementsToRepurchaseIncludingInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_RubberMember" abstract="true" name="RubberMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_SpecialtiesMember" abstract="true" name="SpecialtiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="oec_LongTermIncentivePlanAndOtherNonOperatingCharges" abstract="false" name="LongTermIncentivePlanAndOtherNonOperatingCharges" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="oec_AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization" abstract="false" name="AdjustedEarningsBeforeInterestTaxDepreciationAndAmortization" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
