<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019cfc87-610a-7882-81a3-3eed384785a8,g:8d01c08b-1fb4-4c1f-b927-85019546c0e0-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:ftk="http://flotekind.com/20260331" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2024-01-31" attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://flotekind.com/20260331">
  <xs:import namespace="http://fasb.org/us-gaap-ebp/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/ebp/elts/us-gaap-ebp-2025.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd"/>
  <xs:import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd"/>
  <xs:annotation>
    <xs:appinfo>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ftk-20260331_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ftk-20260331_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ftk-20260331_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xmlns:xlink="http://www.w3.org/1999/xlink" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="ftk-20260331_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple"/>
      <link:roleType id="Cover" roleURI="http://flotekind.com/role/Cover">
        <link:definition>0000001 - Document - Cover</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="STATEMENTSOFFINANCIALCONDITION" roleURI="http://flotekind.com/role/STATEMENTSOFFINANCIALCONDITION">
        <link:definition>0000002 - Statement - STATEMENTS OF FINANCIAL CONDITION</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="STATEMENTSOFNETINCOMEANDCHANGESINPLANEQUITY" roleURI="http://flotekind.com/role/STATEMENTSOFNETINCOMEANDCHANGESINPLANEQUITY">
        <link:definition>0000003 - Statement - STATEMENTS OF NET INCOME AND CHANGES IN PLAN EQUITY</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DESCRIPTIONOFTHEPLAN" roleURI="http://flotekind.com/role/DESCRIPTIONOFTHEPLAN">
        <link:definition>0000004 - Disclosure - DESCRIPTION OF THE PLAN</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIES" roleURI="http://flotekind.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIES">
        <link:definition>0000005 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="TAXSTATUS" roleURI="http://flotekind.com/role/TAXSTATUS">
        <link:definition>0000006 - Disclosure - TAX STATUS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SUBSEQUENTEVENTS" roleURI="http://flotekind.com/role/SUBSEQUENTEVENTS">
        <link:definition>0000007 - Disclosure - SUBSEQUENT EVENTS</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies" roleURI="http://flotekind.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies">
        <link:definition>0000008 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DESCRIPTIONOFTHEPLANDetails" roleURI="http://flotekind.com/role/DESCRIPTIONOFTHEPLANDetails">
        <link:definition>0000009 - Disclosure - DESCRIPTION OF THE PLAN (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="TAXSTATUSDetails" roleURI="http://flotekind.com/role/TAXSTATUSDetails">
        <link:definition>0000010 - Disclosure - TAX STATUS (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:element id="ftk_EBP2012EmployeeStockPurchasePlanMember" abstract="true" name="EBP2012EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ftk_EBPRefundOfContributionsToParticipants" abstract="false" name="EBPRefundOfContributionsToParticipants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftk_EBPEmployeeStockPurchasePlanSharesReservedForIssuance" abstract="false" name="EBPEmployeeStockPurchasePlanSharesReservedForIssuance" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ftk_EBPEmployeeStockPurchasePlanIncreaseInSharesReservedForIssuance" abstract="false" name="EBPEmployeeStockPurchasePlanIncreaseInSharesReservedForIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ftk_EBPEmployeeStockPurchasePlanSharesIssuance" abstract="false" name="EBPEmployeeStockPurchasePlanSharesIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ftk_EBPParticipantContributionPretaxMinimumAnnualCompensationToTotalCompensationPercentage" abstract="false" name="EBPParticipantContributionPretaxMinimumAnnualCompensationToTotalCompensationPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ftk_EBPPercentageOfStockOfClosingMarketPricePercentage" abstract="false" name="EBPPercentageOfStockOfClosingMarketPricePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ftk_EBPEmployeeStockPurchasePriceThreshold" abstract="false" name="EBPEmployeeStockPurchasePriceThreshold" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ftk_EBPMaximumNumberOfSharesPerEmployee" abstract="false" name="EBPMaximumNumberOfSharesPerEmployee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ftk_EBPStockOptionTaxRatePercentage" abstract="false" name="EBPStockOptionTaxRatePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
