Global Mercaptan Market By Type (Hydrogen Sulfide-Methanol Vapor Phase Synthesis, Sodium Sulfide-Dimethyl Sulfate Synthesis, and Thiourea-Dimethyl Sulfate Synthesis), By Application (Animal Nutrition, Pesticides, and Pharmaceuticals), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2019-2028