<SEC-DOCUMENT>0001515156-25-000142.txt : 20251112
<SEC-HEADER>0001515156-25-000142.hdr.sgml : 20251112
<ACCEPTANCE-DATETIME>20251112083042
ACCESSION NUMBER:		0001515156-25-000142
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20251110
FILED AS OF DATE:		20251112
DATE AS OF CHANGE:		20251112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rasmus Robert E.
		CENTRAL INDEX KEY:			0001555130
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37822
		FILM NUMBER:		251469299

	MAIL ADDRESS:	
		STREET 1:		8051 E MAPLEWOOD AVE
		STREET 2:		STE 210
		CITY:			GREENWOOD VILLAGE
		STATE:			CO
		ZIP:			80111

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Arq, Inc.
		CENTRAL INDEX KEY:			0001515156
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		ORGANIZATION NAME:           	08 Industrial Applications and Services
		EIN:				275472457
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		8051 E. MAPLEWOOD AVE., STE 210
		CITY:			GREENWOOD VILLAGE
		STATE:			CO
		ZIP:			80111
		BUSINESS PHONE:		720-598-3500

	MAIL ADDRESS:	
		STREET 1:		8051 E. MAPLEWOOD AVE., STE 210
		CITY:			GREENWOOD VILLAGE
		STATE:			CO
		ZIP:			80111

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Advanced Emissions Solutions, Inc.
		DATE OF NAME CHANGE:	20110311
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wk-form4_1762954239.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-11-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001515156</issuerCik>
        <issuerName>Arq, Inc.</issuerName>
        <issuerTradingSymbol>ARQ</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001555130</rptOwnerCik>
            <rptOwnerName>Rasmus Robert E.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ARQ, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>8051 E MAPLEWOOD AVE STE 210</rptOwnerStreet2>
            <rptOwnerCity>GREENWOOD VILLAGE</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-11-10</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.7918</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>70718</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By RER Investments LLC</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>527779</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By RER Legacy Investments II LLC.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>480782</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This price is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $3.73 to $3.86, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this Form 4.</footnote>
        <footnote id="F2">The shares of Common Stock reported on this row are held by RER Investments LLC (&quot;RER Investments&quot;). Mr. Rasmus, the Chief Executive Officer and a Director of the Issuer, is the ultimate control person of RER Investments, and an indirect beneficial owner of these shares. Mr. Rasmus disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F3">The shares of Common Stock reported on this row are held by RER Legacy Investments II LLC (&quot;RER Legacy&quot;).  Mr. Rasmus, the Chief Executive Officer and a Director of the Issuer, is the ultimate control person of RER Legacy, and an indirect beneficial owner of these shares.  Mr. Rasmus disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Robert E. Rasmus</signatureName>
        <signatureDate>2025-11-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
