Which type of turpentine is obtained as a byproduct of the Kraft paper industry?

Sulfate turpentine is indeed the correct answer because it is a byproduct specifically derived from the Kraft process used in the paper industry. During this pulping process, wood chips are treated with sodium sulfide and sodium hydroxide, which helps break down the lignin in the wood, allowing for the extraction of cellulose fibers. As a result of this chemical reaction, various volatile compounds are released, one of which is sulfate turpentine. This type of turpentine typically contains a mixture of terpenes and is utilized in the production of solvents, resins, and other chemical derivatives.

The other types of turpentine listed do not originate from the Kraft process. For instance, Gum Spirits Turpentine generally comes from the distillation of resin extracted from pine trees, while Standard Turpentine refers more to a general category based on various sources rather than a specific process like Kraft. Refined Turpentine typically refers to turpentine that has undergone further processing for purity and quality, not a specific type related to the Kraft process. Thus, understanding the specific industrial connection of sulfate turpentine aids in affirming its significance in both the painting industry and resource recovery from paper manufacturing.