Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (Nos. 333-220774 and 333-227643) of PQ Group Holdings Inc. of our report dated March 1, 2019 relating to the financial statements, financial statement schedule and effectiveness of internal control over financial reporting, which appears in this Form 10‑K.

/s/ PricewaterhouseCoopers LLP
Philadelphia, Pennsylvania
March 1, 2019