High Pressure Lab Autoclave has robust built reaction vessels that have magnetically coupled, seal-less agitator. The Autoclave is designed with PID controlled electrical heating and cooling arrangements. The Autoclave has flameproof or non-flameproof control panels that indicate pressure, temperature, agitator speed etc and with very high degree of accuracy. The Autoclave ensures faster removal of exotherm and maintaining precise operating temperature is easier despite higher rate of reaction. The Autoclave comes fitted with an agitator which generates very high gas-liquid mass transfer area by recirculation of head space gases. The Autoclave is designed for Hydrogenation and other high pressure gas-liquid reactions. The High Pressure Lab Autoclave has high gas-liquid mass transfer area resulting in faster batch time with optimum catalyst usage.