Anthraquinone-a review of the rise and fall of a pulping catalyst

Abstract

The application of anthraquinone (AQ) as a pulping catalyst has been well documented in scientific studies and mill applications. AQ is known to increase the rate of delignification, enabling a reduction in pulping time, temperature, or chemical charge and an increase in pulp yield. This review does not focus extensively on specific details of AQ use but rather on critical milestones in the AQ process lifecycle, including its initial introduction, investigation of the reaction mechanism, and evaluation of best use by the pulping industry. The importance and difficulty of an economic justification for use of AQ are discussed, including their complication by modest improvement in yield obtained using AQ and low cost of the displaced chemicals. In many mills, documenting increased net mill revenue resulting from the use of AQ has been impossible. Recent health and safety studies and regulatory decisions have put the continuing use of AQ by industry in jeopardy. Given the unknown health risks, international regulatory environment, modest improvements available using AQ, and difficulty in economically accounting for the benefits, this likely represents the final chapter in the AQ life cycle.

Competition of Intra- and Intermolecular Forces in Anthraquinone and Its Selected Derivatives

“…The group of anthraquinones is believed to be the largest family of naturally occurring quinone derivatives. Anthraquinone and its derivatives found some practical application as, e.g., digester additive in production of paper pulp by alkaline processes [ 15 ] or as an electrolyte in flow battery which can provide long term electrical storage [ 16 ]. Additionally, anthraquinone is a well-known building block of many dyes, which could be divided into natural and synthetic [ 17 ].…”

Response Surface Methodology on the Effects of Soda – Anthraquinone Pulping Conditions on Oil Palm Empty Fruit Bunches Pulp Properties

“…AQ is known to increase the rate of delignification, enabling a reduction in pulping time, temperature, or chemical charge and an increase in pulp yield. However, Hart & Rudie also highlighted that due to unknown health risk, recently, many pulp and paper companies had decided to stop using AQ in the production of direct food contact products [16].…”

Chlorine dioxide bleaching of nineteen non-wood plant pulps

“…Studies have shown that the soda anthraquinone (AQ) pulping is the widely accepted process for efficient conversion of non-woods into pulp without with faster delignification (Hart and Rudie 2014). The major part of delignification occurs during the pulping process and rest is removed further in bleaching stages.…”