Usage of Artificial Intelligence Large Language Models (LLMs) in the Chemical Industry: A Comprehensive Review

The rapid advancement of Large Language Models (LLMs) is fundamentally transforming the chemical industry across its entire value chain. This paper provides a comprehensive IEEE-structured review of how AI-powered LLMs—including GPT-4, Claude, Gemini, and domain-specific models such as ChemLLM, ChemCrow, and Coscientist—are deployed across key chemical industry segments: drug discovery, specialty chemical synthesis, process optimization, predictive maintenance, supply chain management, safety and regulatory compliance, and materials science. Drawing on peer-reviewed literature and industry reports published between 2022 and 2025, this paper identifies transformative applications, quantifies performance improvements, and critically evaluates persistent technical and regulatory challenges. Findings demonstrate that LLMs can accelerate molecular discovery timelines by 30–70%, reduce process downtime through predictive maintenance, automate complex compliance documentation, and support real-time decision-making in chemical plant operations. Significant barriers remain, including hallucination in safety-critical contexts, industrial data scarcity, regulatory uncertainty, and integration