Synthesis of p-aminophenol from p-chloronitrobenzene involves mixing p-chloronitrobenzene in sodium hydroxide solution to obtain reaction mixture, heating and filtering to obtain sodium-nitrophenolate salt, which is further mixed with water and hydrogenation catalyst to obtain mixture and heating
	DHOTRE K D; TARADE K P; BHONGALE S S; KAMBLE S P
	2023-09-05
专利权人	COUNCIL SCI & IND RES SOUTH AFRICA (COUL-C)
申请日期	2023-09-05
专利号	IN202311061153-A
成果简介	NOVELTY - Synthesis of p-aminophenol (PAP) from p-chloronitrobenzene (PCNB) involves (a) dissolving NaOH in water to obtain NaOH solution, (b) mixing p-chloronitrobenzene (PCNB) in the sodium hydroxide (NaOH) solution to obtain a reaction mixture, (c) heating the reaction mixture at 150-220℃ with agitation speed in the range of 300-1400 RPM for a time period in the range of 1-5 hours to obtain a reaction mixture, (d) filtering the reaction mixture to obtain Na-nitrophenolate salt with selectivity in the range of 95-99% and a mother liquor-1 containing spent water, (e) distilling out the filtered mother liquor -1 under vacuum at 60-80℃ and pressure in the range of 100-120 mbar to obtain a distillate, where distillate is pure water, (f) mixing the Na-nitrophenolate salt with water and a hydrogenation catalyst to obtain a reaction mixture, and (g) heating the reaction mixture at 150-190°C, hydrogen pressure in the range of 2-15 bar for a time period in the range of 3-7 hrs. USE - Synthesis of p-aminophenol (PAP) from p-chloronitrobenzene (PCNB) used in the production of paracetamol & dyestuffs. ADVANTAGE - The productivity of process is increased, and water consumption is reduced, and overall plant footprint required is less in this process. The process gives complete conversion of pchloronitrobenzene with 97-99 % selectivity for Na-nitrophenolate, gives complete conversion of pchloronitrobenzene with 97-99 % selectivity for Na-nitrophenolate and further Ni0 catalyzed hydrogenation of Na-nitrophenolate to Na-aminophenolate subsequently its acidification gives p-aminophenol (PAP), maximum conversion of p-chloronitrobenzene with high yield for p-aminophenol, excellent selectivity to Na-nitrophenolate which can further hydrogenated to Na-aminophenolate, and later to aminophenol, widely used in the production of paracetamol & dyestuffs. The catalyst system is extremely stable and reusable. The systematic protocol for recycle and reuse of wastewater in the both steps i.e. conversion of PNCB to Na-nitrophenolate and hydrogenation of Nanitrophenolate to Na- aminophenolate. The catalyst is recycled and reused multiple times without losing its activity hence. The catalyst disposal problem will be suppressed. The Na-nitrophenolate is highly soluble in water hence productivity of p-aminophenol is increased. The water consumption in process decreased hence waste water generation is minimized. DETAILED DESCRIPTION - Synthesis of p-aminophenol (PAP) from p-chloronitrobenzene (PCNB) involves (a) dissolving NaOH in water to obtain NaOH solution, (b) mixing p-chloronitrobenzene (PCNB) in the sodium hydroxide (NaOH) solution to obtain a reaction mixture, (c) heating the reaction mixture at 150-220° C with agitation speed in the range of 300-1400 RPM for a time period in the range of 1-5 hours to obtain a reaction mixture, (d) filtering the reaction mixture to obtain Na-nitrophenolate salt with selectivity in the range of 95-99% and a mother liquor-1 containing spent water, (e) distilling out the filtered mother liquor -1 under vacuum at 60-80℃ and pressure in the range of 100-120 mbar to obtain a distillate, where the distillate is pure water, (f) mixing the Na-nitrophenolate salt with water and a hydrogenation catalyst to obtain a reaction mixture, (g) heating the reaction mixture at 150-190°C, hydrogen pressure in the range of 2-15 bar for a time period in the range of 3-7 hrs to obtain a mixture of Na-aminophenolate, (h) filtering the mixture of sodium-aminophenolate at 70-90°C to recover catalyst and crude sodium aminophenolate, (i) adding an acid solution dropwise to the crude Na-aminophenolate as obtained in step (h) under continuous stirring at 25-35℃ for a time period in the range of 0.5-2 hours to obtain a mixture, and (j) filtering the mixture to obtain 82-88% p-aminophenol with 90-97% selectivity and a mother liquor-2 containing spent water, (k) distilling out the filtered mother liquor under vacuum at a temperature in the range of 60-80°C and pressure in the range of 100-120 mbar to obtain a distillate, where the distillate is pure water, that is recyclable and reusable.
IPC 分类号	C07C-213/00 ; C07C-215/76
国家	印度
专业领域	医药卫生
语种	英语
成果类型	专利
文献类型	科技成果
条目标识符	http://119.78.100.226:8889/handle/3KE4DYBR/20509
专题	中国科学院新疆生态与地理研究所
作者单位	COUNCIL SCI & IND RES SOUTH AFRICA (COUL-C)
推荐引用方式 GB/T 7714	DHOTRE K D,TARADE K P,BHONGALE S S,et al. Synthesis of p-aminophenol from p-chloronitrobenzene involves mixing p-chloronitrobenzene in sodium hydroxide solution to obtain reaction mixture, heating and filtering to obtain sodium-nitrophenolate salt, which is further mixed with water and hydrogenation catalyst to obtain mixture and heating. IN202311061153-A[P]. 2023.

条目包含的文件
条目无相关文件。

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。