Supercritical process for linear alkylbenzene sulfonate production

该项目涉及一种制造商业可生物降解洗涤剂的关键成分的新工艺。在过去的十年里，我们对二氧化硫在活性碳上的氧化反应进行了研究，发现超临界二氧化碳能够从活性碳表面提取强吸附的三氧化硫。这使得生产三氧化硫的一种简单的常温工艺成为可能，三氧化硫是一种对工业具有很高价值的关键磺化/硫化试剂。活性碳是二氧化硫氧化的一种活性极高的催化剂。因此，二氧化硫和氧气(或空气)通过活性碳床形成三氧化硫，三氧化硫被强烈吸附在碳上。在第二步中，超临界二氧化碳将三氧化硫从碳中剥离，得到含有三氧化硫的凝聚相。我们已经实验证明，在40℃以下的鼓泡塔中，无论是稠相还是气相(降压产生的)与商业直链烷基苯接触，都需要消耗所有的三氧化硫来定量生产直链烷基苯磺酸盐，直链烷基苯磺酸盐是商业洗涤剂的重要成分。我们的初步实验表明没有副作用，因此我们有了一种新的、低温的、环境友好的洗涤剂生产工艺。

This project deals with a new process for making a key ingredient of commercial, biodegradable detergents. Our investigations of the oxidation of sulfur dioxide over activated carbon during the past decade has led to the discovery that supercitical carbon dioxide is able to extract strongly adsorbed sulfur trioxide from the surface of activated carbon. This makes possible a simple, room temperature process for the production of sulfur trioxide, a key sulfonation/sulfation reagent of high value to industry. Activated carbon is an extremely active catalyst for sulfur dioxide oxidation. Thus, sulfur dioxide and oxygen (or air) pass through a bed of activated carbon forming sulfur trioxide, which is strongly adsorbed on the carbon. In a second step, sulfur trioxide is stripped from the carbon by supercritical carbon dioxide to give a condensed phase containing sulfur trioxide. We have demonstrated experimentally that contacting either the dense phase or a gas phase (produced by depressurization) with commercial linear alkylbenzene in a bubble column at under 40 C consumes all the sulfur trioxide to quantitatively produce linear alkylbenzene sulfonate, an important ingredient of commercial detergents. Our preliminary experiments indicate no side reactions so that we have a new, low temperature, environmentally benign process for detergent manufacture.