# EDGAR Filing Document

**Accession Number:** 0001708035
**File Stem:** 0000899243-23-000592
**Filing Date:** 2023-1
**Character Count:** 8117
**Document Hash:** ea3adea7af705680d2bb4066f90ac335
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000899243-23-000592.hdr.sgml**: 20230104

**ACCESSION NUMBER**: 0000899243-23-000592

**CONFORMED SUBMISSION TYPE**: 3

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20230101

**FILED AS OF DATE**: 20230104

**DATE AS OF CHANGE**: 20230104

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Whittleston Paul
- **CENTRAL INDEX KEY:** 0001958277

**FILING VALUES:**
- **FORM TYPE:** 3
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38221
- **FILM NUMBER:** 23506556

**MAIL ADDRESS:**
- **STREET 1:** C/O ECOVYST INC.
- **STREET 2:** 300 LINDENWOOD DRIVE
- **CITY:** MALVERN
- **STATE:** PA
- **ZIP:** 19355
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Ecovyst Inc.
- **CENTRAL INDEX KEY:** 0001708035
- **STANDARD INDUSTRIAL CLASSIFICATION:** CHEMICALS & ALLIED PRODUCTS [2800]
- **IRS NUMBER:** 813406833
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 300 LINDENWOOD DRIVE
- **CITY:** MALVERN
- **STATE:** PA
- **ZIP:** 19355
- **BUSINESS PHONE:** 484-617-1200

**MAIL ADDRESS:**
- **STREET 1:** 300 LINDENWOOD DRIVE
- **CITY:** MALVERN
- **STATE:** PA
- **ZIP:** 19355

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** PQ Group Holdings Inc.
- **DATE OF NAME CHANGE:** 20170531

## Exhibit 24.1

```
<PRE>
                                                                    Exhibit 24.1
                               POWER OF ATTORNEY

     The undersigned hereby constitutes and appoints Joseph S. Koscinski with
full power of substitution, as the undersigned's true and lawful
attorney-in-fact to:

     (1)   prepare, execute in the undersigned's name and on the undersigned's
           behalf, and submit to the U.S. Securities and Exchange Commission
           (the "SEC") a Form ID, including amendments thereto, and any other
           documents necessary or appropriate to obtain codes and passwords
           enabling the undersigned to make electronic filings with the SEC of
           reports required by Section 16(a) of the Securities Exchange Act of
           1934, as amended, or any rule or regulation of the SEC;

     (2)   execute for and on behalf of the undersigned, in the undersigned's
           capacity as officer and/or director of PQ Group Holdings Inc. (the
           "Company"), Forms 3, 4, and 5 in accordance with Section 16(a) of the
           Securities Exchange Act of 1934, as amended, and the rules
           thereunder;

     (3)   do and perform any and all acts for and on behalf of the undersigned
           that may be necessary or desirable to complete and execute any such
           Form 3, 4, or 5, complete and execute any amendment or amendments
           thereto, and timely file such form with the SEC and any stock
           exchange or similar authority; and

     (4)   take any other action of any type whatsoever in connection with the
           foregoing that, in the opinion of such attorney-in-fact, may be of
           benefit to, in the best interest of, or legally required by, the
           undersigned, it being understood that the documents executed by such
           attorney-in-fact on behalf of the undersigned pursuant to this Power
           of Attorney shall be in such form and shall contain such terms and
           conditions as such attorney-in-fact may approve in such
           attorney-in-fact's discretion.

     The undersigned hereby grants to such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be
done by virtue of this power of attorney and the rights and powers herein
granted.  The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities to comply
with Section 16 of the Securities Exchange Act of 1934, as amended.

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorney-in-fact.

                  [Remainder of page intentionally left blank]

     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of the 6th day of December, 2022.

                                           /s/ Paul Whittleston
                                           ----------------------
                                           Paul Whittleston

                 [Signature Page to Limited Power of Attorney]

</PRE>
```

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 3

### INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Whittleston Paul<br><sub>(Last) (First) (Middle)</sub><br>C/O ECOVYST INC.<br>300 LINDENWOOD DRIVE<br><sub>(Street)</sub><br>MALVERN, PA 19355<br><sub>(City) (State) (Zip)</sub> | **3. Issuer Name and Ticker or Trading Symbol**<br>Ecovyst Inc. [ ECVT ] | **5. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  |
| **2. Date of Event Requiring Statement (Month/Day/Year)**<br>2023-01-01 | **4. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director   [ ] 10% Owner<br>[X] Officer (give title below)   [ ] Other (specify below)<br>_See Remarks_ | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities Beneficially Owned

---

|  |  |  |  |
| --- | --- | --- | --- |
| 1. Title of Security | 2. Amount of Securities Beneficially Owned | 3. Ownership Form | 4. Nature of Indirect Beneficial Ownership |

---

## Table II - Derivative Securities Beneficially Owned

---

|  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 2. Date Exercisable and Expiration Date (Month/Day/Year) | 3. Title and Amount of Underlying Securities | 3. Title and Amount of Underlying Securities | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 4. Conversion or Exercise Price | 5. Ownership Form | 6. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |

---

**Remarks:**
President, Catalyst Technologies

Exhibit 24.1 - Power of Attorney

**Signature:** /s/ Joseph S. Koscinski, as attorney-in-fact for Paul Whittleston  
**Date:** 2023-01-04

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**