▎ 摘　　要

NOVELTY - Preparing 2-methyl-3-thiosemicarbazide involves mixing 40 wt.% of aqueous solution of methylhydrazine with 1.6-5 wt.% of graphene and 220 g of ammonium thiocyanate. The mixture is slowly warmed to 0-80 degrees C, then insulated for 0-60 minutes, maintained under pressure of 0.02-0.08 MPa. The reactant mixture is heated to 100-110 degrees C and allowed to crystallize slowly and then added to 500 ml of tap water at normal pressure. The resultant is heated to 90 degrees C and then filtered hot under suction to obtain graphene which is dried at 20-50 degrees C in oven for re-use. USE - Method for preparing 2-methyl-3-thiosemicarbazide (claimed). ADVANTAGE - The method enables to improve yield of 2-methyl-3-thiosemicarbazide in simple and cost effective manner which is suitable for large scale production. DETAILED DESCRIPTION - Preparing 2-methyl-3-thiosemicarbazide involves mixing 40 wt.% of aqueous solution of methylhydrazine with 1.6-5 wt.% of graphite and 220 g of ammonium thiocyanate. The mixture is slowly warmed to 0-80 degrees C, then insulated for 0-60 minutes, maintained under pressure of 0.02-0.08 MPa. The reactant mixture is heated to 100-110 degrees C and allowed to crystallize slowly and then added to 500 ml of tap water at normal pressure. The resultant is heated to 90 degrees C and then filtered hot under suction to obtain graphene which is dried at 20-50 degrees C in oven for re-use. The filtrate is cooled down to 30 degrees C and filtered under suction to obtain product which is dried at 80-100 degrees C to obtain 2-methylthiosemicarbazone.