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  <xsd:element abstract="true" id="ftek_statement-statement-note-2-summary-of-significant-accounting-policies-allowance-for-doubtful-accounts-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-allowance-for-doubtful-accounts-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-summary-of-significant-accounting-policies-amortized-cost-to-fair-value-of-htm-debt-securities-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-amortized-cost-to-fair-value-of-htm-debt-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-summary-of-significant-accounting-policies-debt-securities-by-maturity-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-debt-securities-by-maturity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-summary-of-significant-accounting-policies-reconciliation-of-cash-cash-equivalents-and-restricted-cash-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-reconciliation-of-cash-cash-equivalents-and-restricted-cash-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-summary-of-significant-accounting-policies-tables" name="statement-statement-note-2-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-revenue-components-of-accounts-receivable-details" name="statement-statement-note-3-revenue-components-of-accounts-receivable-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-revenue-revenues-disaggregated-by-geography-details" name="statement-statement-note-3-revenue-revenues-disaggregated-by-geography-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-revenue-revenues-disaggregated-by-product-technology-details" name="statement-statement-note-3-revenue-revenues-disaggregated-by-product-technology-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-revenue-tables" name="statement-statement-note-3-revenue-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-revenue-timing-of-revenue-recognition-details" name="statement-statement-note-3-revenue-timing-of-revenue-recognition-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-4-restructuring-activities-charges-and-net-assets-details" name="statement-statement-note-4-restructuring-activities-charges-and-net-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-4-restructuring-activities-tables" name="statement-statement-note-4-restructuring-activities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-5-accumulated-other-comprehensive-loss-accumulated-other-comprehensive-loss-details" name="statement-statement-note-5-accumulated-other-comprehensive-loss-accumulated-other-comprehensive-loss-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-5-accumulated-other-comprehensive-loss-tables" name="statement-statement-note-5-accumulated-other-comprehensive-loss-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-7-earnings-per-share-earnings-per-share-details" name="statement-statement-note-7-earnings-per-share-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-7-earnings-per-share-tables" name="statement-statement-note-7-earnings-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-8-stockbased-compensation-restricted-stock-activity-details" name="statement-statement-note-8-stockbased-compensation-restricted-stock-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-8-stockbased-compensation-stock-option-activity-details" name="statement-statement-note-8-stockbased-compensation-stock-option-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-8-stockbased-compensation-stockbased-compensation-details" name="statement-statement-note-8-stockbased-compensation-stockbased-compensation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-8-stockbased-compensation-tables" name="statement-statement-note-8-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-9-warrants-summary-of-warrants-outstanding-and-exercisable-details" name="statement-statement-note-9-warrants-summary-of-warrants-outstanding-and-exercisable-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-9-warrants-tables" name="statement-statement-note-9-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
