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  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-accumulated-other-comprehensive-income-details" name="statement-statement-note-1-organization-and-significant-accounting-policies-accumulated-other-comprehensive-income-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-allowance-for-doubtful-accounts-details" name="statement-statement-note-1-organization-and-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-1-organization-and-significant-accounting-policies-amortized-cost-to-fair-value-of-htm-debt-securities-details" name="statement-statement-note-1-organization-and-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-1-organization-and-significant-accounting-policies-debt-securities-by-maturity-details" name="statement-statement-note-1-organization-and-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-1-organization-and-significant-accounting-policies-estimated-future-amortization-expense-details" name="statement-statement-note-1-organization-and-significant-accounting-policies-estimated-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-property-and-equipment-details" name="statement-statement-note-1-organization-and-significant-accounting-policies-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-reconciliation-of-cash-cash-equivalents-and-restricted-cash-details" name="statement-statement-note-1-organization-and-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-1-organization-and-significant-accounting-policies-summary-of-earnings-loss-per-share-details" name="statement-statement-note-1-organization-and-significant-accounting-policies-summary-of-earnings-loss-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-summary-of-intangible-asset-activity-details" name="statement-statement-note-1-organization-and-significant-accounting-policies-summary-of-intangible-asset-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-1-organization-and-significant-accounting-policies-tables" name="statement-statement-note-1-organization-and-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-10-leases-lease-liabilities-details" name="statement-statement-note-10-leases-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-10-leases-operating-lease-expense-details" name="statement-statement-note-10-leases-operating-lease-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-10-leases-remaining-maturities-of-existing-lease-liabilities-details" name="statement-statement-note-10-leases-remaining-maturities-of-existing-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-10-leases-supplemental-cash-flow-information-details" name="statement-statement-note-10-leases-supplemental-cash-flow-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-10-leases-tables" name="statement-statement-note-10-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-12-business-segment-and-geographic-financial-data-geographic-segment-financial-data-details" name="statement-statement-note-12-business-segment-and-geographic-financial-data-geographic-segment-financial-data-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-12-business-segment-and-geographic-financial-data-reporting-segment-net-sales-and-gross-margin-details" name="statement-statement-note-12-business-segment-and-geographic-financial-data-reporting-segment-net-sales-and-gross-margin-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-12-business-segment-and-geographic-financial-data-tables" name="statement-statement-note-12-business-segment-and-geographic-financial-data-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-13-restructuring-activities-charges-and-net-assets-details" name="statement-statement-note-13-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-13-restructuring-activities-tables" name="statement-statement-note-13-restructuring-activities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-14-accrued-liabilities-components-of-other-accrued-liabilities-details" name="statement-statement-note-14-accrued-liabilities-components-of-other-accrued-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-14-accrued-liabilities-tables" name="statement-statement-note-14-accrued-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-revenue-recognition-components-of-accounts-receivable-details" name="statement-statement-note-2-revenue-recognition-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-2-revenue-recognition-revenues-disaggregated-by-geography-details" name="statement-statement-note-2-revenue-recognition-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-2-revenue-recognition-revenues-disaggregated-by-product-technology-details" name="statement-statement-note-2-revenue-recognition-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-2-revenue-recognition-tables" name="statement-statement-note-2-revenue-recognition-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-2-revenue-recognition-timing-of-revenue-recognition-details" name="statement-statement-note-2-revenue-recognition-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-3-income-taxes-cash-taxes-paid-details" name="statement-statement-note-3-income-taxes-cash-taxes-paid-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-components-of-income-loss-domestic-and-foreign-details" name="statement-statement-note-3-income-taxes-components-of-income-loss-domestic-and-foreign-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-components-of-income-tax-expense-details" name="statement-statement-note-3-income-taxes-components-of-income-tax-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-income-tax-rate-reconciliation-details" name="statement-statement-note-3-income-taxes-income-tax-rate-reconciliation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-summary-of-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-3-income-taxes-summary-of-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-tables" name="statement-statement-note-3-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-unrecognized-tax-benefit-details" name="statement-statement-note-3-income-taxes-unrecognized-tax-benefit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-3-income-taxes-valuation-allowances-details" name="statement-statement-note-3-income-taxes-valuation-allowances-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-7-warrants-summary-of-warrants-outstanding-and-exercisable-details" name="statement-statement-note-7-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-7-warrants-tables" name="statement-statement-note-7-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="ftek_statement-statement-note-7-warrants-warrant-activity-details" name="statement-statement-note-7-warrants-warrant-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-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-summary-of-outstanding-stock-options-by-exercise-price-range-details" name="statement-statement-note-8-stockbased-compensation-summary-of-outstanding-stock-options-by-exercise-price-range-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-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
