Specialty chemicals from CO2 and electricity

Evonik and Siemens are plan­ning to use elec­tric­i­ty from renew­able sources and bac­te­ria to con­vert car­bon diox­ide into spe­cial­ty chem­i­cals. The two com­pa­nies are work­ing on elec­trol­y­sis and fer­men­ta­tion process­es in a joint research project called Rheti­cus. The project was launched today and is due to run for two years. The first test plant is sched­uled to go on stream by 2021 at the Evonik facil­i­ty in Marl, Ger­many which pro­duces chem­i­cals such as butanol and hexa­nol, both feed­stocks for spe­cial plas­tics and food sup­ple­ments, for exam­ple. The next stage could see a plant with a pro­duc­tion capac­i­ty of up to 20,000 tonnes a year. There is also poten­tial to man­u­fac­ture oth­er spe­cial­ty chem­i­cals or fuels. Some 20 sci­en­tists from the two com­pa­nies are involved in the project.
“We are devel­op­ing a plat­form that will allow us to pro­duce chem­i­cal prod­ucts in a much more cost-effec­tive and envi­ron­men­tal­ly-friend­ly way than we do today”, explains Dr. Gün­ter Schmid, tech­ni­cal project respon­si­ble of Siemens Cor­po­rate Tech­nol­o­gy. “Using our plat­form, oper­a­tors will in future be able to scale their plants to suit their needs.” The new tech­nol­o­gy com­bines mul­ti­ple ben­e­fits. It not only enables chem­i­cals to be pro­duced sus­tain­ably, it also serves as an ener­gy store, can respond to pow­er fluc­tu­a­tions and help sta­bi­lize the grid. Rheti­cus is linked to the Kopernikus Ini­tia­tive for the ener­gy tran­si­tion in Ger­many which is seek­ing new solu­tions to restruc­ture the ener­gy sys­tem. The Rheti­cus project will receive 2.8 mil­lion euros in fund­ing from Germany’s Fed­er­al Min­istry of Edu­ca­tion and Research (BMBF).
“With the Rheti­cus plat­form, we want to demon­strate that arti­fi­cial pho­to­syn­the­sis is fea­si­ble”, adds Dr. Thomas Haas, who is respon­si­ble for the project in Evonik’s strate­gic research depart­ment Creav­is. Arti­fi­cial pho­to­syn­the­sis is where CO₂ and water are con­vert­ed into chem­i­cals using a com­bi­na­tion of chem­i­cal and bio­log­i­cal steps, in a process sim­i­lar to how leaves use chloro­phyll and enzymes to syn­the­size glucose.

Siemens and Evonik are each con­tribut­ing their own core com­pe­ten­cies to this research col­lab­o­ra­tion. Siemens is pro­vid­ing the elec­trol­y­sis tech­nol­o­gy, which is used in the first step to con­vert car­bon diox­ide and water into hydro­gen and car­bon monox­ide (CO) using elec­tric­i­ty. Evonik is con­tribut­ing the fer­men­ta­tion process, con­vert­ing gas­es con­tain­ing CO into use­ful prod­ucts by meta­bol­ic process­es with the aid of spe­cial micro-organ­isms. In the Rheti­cus project, these two steps – elec­trol­y­sis and fer­men­ta­tion – are scaled up from the lab­o­ra­to­ry and com­bined in a tech­ni­cal test facility.
“Rheti­cus brings togeth­er the exper­tise of Evonik and Siemens. This research project shows how we are apply­ing the Pow­er-to‑X idea”, says Dr. Karl Eugen Hut­mach­er from the BMBF. Using elec­tric­i­ty to gen­er­ate chem­i­cals is an idea from the Pow­er-to‑X con­cept. As one of the four pil­lars of the Kopernikus Ini­tia­tive, the idea is to help con­vert and store renew­able, elec­tri­cal ener­gy effi­cient­ly. At the same time, the Rheti­cus plat­form also con­tributes to the reduc­tion of car­bon diox­ide lev­els in the atmos­phere, as it uses CO₂ as a raw mate­r­i­al. Three tons of car­bon diox­ide would be need­ed to pro­duce one tonne of butanol, for example.
Evonik and Siemens see great future poten­tial in the Rheti­cus plat­form. It will make it sim­ple to scale plants to the desired size – the chem­i­cal indus­try will be able to adapt them flex­i­bly to local con­di­tions. In future, they could be installed any­where where there is a source of CO₂ – pow­er plant waste gas or bio­gas for instance.
“Its mod­u­lar nature and flex­i­bil­i­ty in terms of loca­tion, raw mate­r­i­al sources and prod­ucts man­u­fac­tured make the new plat­form attrac­tive for the spe­cial­ty chem­i­cals indus­try in par­tic­u­lar”, says Haas. “We are con­fi­dent that oth­er com­pa­nies will use the plat­form and inte­grate it with their own mod­ules to man­u­fac­ture their chem­i­cal prod­ucts”, adds Schmid.
Cov­er pic­ture: In the fer­men­ta­tion process—here at lab scale—, spe­cial bac­te­ria are con­vert­ing CO-con­tain­ing gas­es to valu­able chem­i­cals through meta­bol­ic process­es. (Source: Evonik)