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  <xs:element id="tti_StandardLithiumLtd.Member" abstract="true" name="StandardLithiumLtd.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_InvestmentsOtherMember" abstract="true" name="InvestmentsOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tti_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_AssetBasedCreditAgreementMember" abstract="true" name="AssetBasedCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_SwedishCreditFacilityMember" abstract="true" name="SwedishCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_FinlandCreditAgreementMember" abstract="true" name="FinlandCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_DelayedDrawTermLoanDDTLMember" abstract="true" name="DelayedDrawTermLoanDDTLMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tti_SinglineLoanMember" abstract="true" name="SinglineLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tti_FedFundsEffectiveRateMember" abstract="true" name="FedFundsEffectiveRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tti_SecuredOvernightFinancingRateSOFRAdjustedForRequiredBankReservesMember" abstract="true" name="SecuredOvernightFinancingRateSOFRAdjustedForRequiredBankReservesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tti_DebtInstrumentCovenantLeverageRatioMaximum" abstract="false" name="DebtInstrumentCovenantLeverageRatioMaximum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tti_DebtInstrumentCovenantLiquidityMinimumAmount" abstract="false" name="DebtInstrumentCovenantLiquidityMinimumAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tti_LineOfCreditFacilityAdditionalBorrowingCapacity" abstract="false" name="LineOfCreditFacilityAdditionalBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tti_DebtInstrumentCollateralPercentageOfEquityInterestInCertainForeignSubsidiaries" abstract="false" name="DebtInstrumentCollateralPercentageOfEquityInterestInCertainForeignSubsidiaries" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="tti_OffshoreDivisionMember" abstract="true" name="OffshoreDivisionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_MaritechMember" abstract="true" name="MaritechMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_InitialBondsMember" abstract="true" name="InitialBondsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_InterimReplacementBondsMember" abstract="true" name="InterimReplacementBondsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tti_DiscontinuedOperationAmountsOfMaterialContingentLiabilitiesRemainingPerformanceBonds" abstract="false" name="DiscontinuedOperationAmountsOfMaterialContingentLiabilitiesRemainingPerformanceBonds" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
