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  <xs:element id="ecvt_PerformanceStockUnitFairValueAssumptionsRiskFreeInterestRate" abstract="false" name="PerformanceStockUnitFairValueAssumptionsRiskFreeInterestRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ecvt_PerformanceStockUnitFairValueAssumptionsExpectedVolatilityRate" abstract="false" name="PerformanceStockUnitFairValueAssumptionsExpectedVolatilityRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ecvt_PerformanceStockUnitFairValueAssumptionsExpectedTerm" abstract="false" name="PerformanceStockUnitFairValueAssumptionsExpectedTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ecvt_IncrementalCommonSharesExcludedFromComputationOfEarningsPerShareAmount" abstract="false" name="IncrementalCommonSharesExcludedFromComputationOfEarningsPerShareAmount" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ecvt_RestrictedStockRestrictedStockUnitsRSUsandPerformanceStockUnitsPSUsMember" abstract="true" name="RestrictedStockRestrictedStockUnitsRSUsandPerformanceStockUnitsPSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ecvt_NonCashInvestingItemsAbstract" abstract="true" name="NonCashInvestingItemsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ecvt_NonCashFinancingActivityAbstract" abstract="true" name="NonCashFinancingActivityAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
</xs:schema>
