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Ralph Landau (May 19, 1916 – April 5, 2004)[1] was a chemical engineer and entrepreneur active in the chemical and petrochemical industries.[3][4] He is considered one of the top fifty foundational chemical engineers of the first half of the 20th century,[5] and one of the 75 most distinguished contributors to chemical enterprise.[6] He has published extensively on chemical engineering[1] and holds a significant number of patents.[7]

Ralph Landau
Ralph Landau othmer luncheon 1997.tif
Ralph Landau, Othmer medal recipient, 1997
Born(1916-05-19)May 19, 1916
DiedApril 5, 2004(2004-04-05) (aged 87)
CitizenshipAmerican
Spouse(s)Dr. Claire Landau
ChildrenDr. Laurie J. Landeau[1][2]
AwardsOthmer Gold Medal, National Medal of Technology, Perkin Medal
Scientific career
FieldsChemistry

In his 60s, he began a productive second career in economics at Stanford and Harvard Universities, examining economic theory, economic history and the application of technology in the chemical industry.[8][9] His economic work focuses on understanding the political and economic environment necessary to encourage technological innovation. He published more than 143 papers and nine books.[1]

Ralph Landau won a number of significant awards, including a Lifetime Achievement Award from the Lester Center for Entrepreneurship & Innovation (2003),[4] the first Othmer Gold Medal (1997),[10][11] the National Medal of Technology from the United States Government,[12] first awarded by President Ronald Reagan in 1985 "for his technical, leadership and entrepreneurial roles in the development of commercially successful petrochemical processes", and the Perkin Medal (1981).[13]

Early life and educationEdit

Ralph Landau was born in Philadelphia, Pennsylvania, where he received his primary and secondary education. At age 16, while at Overbrook High School in West Philadelphia, he won a Mayor's Scholarship to attend the University of Pennsylvania.[3][9] He graduated from the University of Pennsylvania with a bachelor of science degree in chemical engineering in 1937.

He went on to attend the Massachusetts Institute of Technology. He received funding from a national Tau Beta Pi fellowship, applicable at the university of his choice, and further financed his doctoral work by working as a teaching assistant and research assistant.[14] :xvi As part of the MIT program Landau participated in the Practice School. His industrial placements included a steel mill in Buffalo, New York, a paper mill in Bangor, Maine, and a chemical plant in Parlin, New Jersey.[14] :xvi He also worked in a placement at M. W. Kellogg Company, helping to design petroleum refining plants in the summer of 1939.[14] :xvi He received an Sc.D. in chemical engineering from MIT in 1941.[3]

On July 14, 1940, Ralph Landau married Claire Sackler. They have a daughter, Laurie J. Landeau [sic].[1]

M. W. Kellogg CompanyEdit

From 1941 to 1946, Landau worked as a process development engineer for the New Jersey-based M. W. Kellogg Company, one of the first engineering firms to specialize in design and development for the oil refining and chemical industries.[3][15] Landau was initially involved in research on catalytic cracking.[3] Kellogg and several other companies wanted to develop techniques for fluid catalytic cracking that would not infringe on Eugene Houdry's patents for fixed-bed cracking.[16][17][18][19]

Kellex CorporationEdit

 
The K-25 building of the Oak Ridge Gaseous Diffusion Plant

During World War II, M. W. Kellogg created a subsidiary company, Kellex Corporation, for work on the Manhattan Project. Scientists at Kellex attempted to design a production-scale facility to produce Uranium-235 for the atomic bomb. Through a process called gaseous diffusion, isotopes of U-235 were separated from the predominant isotope, Uranium-238 by turning uranium metal into uranium hexaflouride gas and straining it through a barrier material.[20]

In 1943 Landau was invited to transfer to Kellogg's subsidiary, Kellex Corporation, to become head of the chemical department at the Manhattan Project's K-25 production plant at Oak Ridge, Tennessee.[1][3] Landau designed equipment to produce fluorine, a highly reactive substance used to make the uranium hexafluoride for the gaseous diffusion process. He also oversaw the production of the fluorinated compounds used to protect surfaces in contact with uranium hexafluoride,[14] :xvii[21][22] such as the perfluorocarbons perfluoroheptane and perfluoroxylene.[23]

Scientific Design Co.Edit

In 1946, Landau co-founded Scientific Design Co., Inc. with Harry Rehnberg and Robert Egbert.[24][25] Rehnberg was a construction engineer at Kellex, involved in building the fluorine unit Landau had designed. He became Scientific Design Co.'s first president, and Landau the executive vice president.[14]:xviii Scientific Design's intention was to design and create chemical processing technologies for use in the newly developing area of petrochemicals.[26] At the time, most oil companies relied on outside research for process innovation. Scientific Design and other companies worked with clients to develop and pilot new chemical manufacturing processes, then patented and licensed those technologies for wider sales.[27] Such specialized engineering firms accounted for 18% of new developments.[28]

After completing an initial contract with Stauffer Chemical, Scientific Design bought a laboratory near 32nd St and Park Avenue in New York City.[14]:xviii

Ethylene oxide and ethylene glycolEdit

The company’s first big success was the development of processes for the direct oxidation of ethylene to ethylene oxide, and transformation of ethylene oxide to ethylene glycol in the early 1950s.[29][30] Ethylene oxide, a gas, was used for synthesis of ethylene glycol. Ethylene glycol, a liquid, was used to manufacture polyethylene terephthalate resins (PET) for the bottling industry, antifreeze for automobile and airplane engines,[2] and polyester fibers, a material increasingly used the fabric industry.[24]

At the time, oxidation processes tended to use expensive oxidants such as nitric acid, chlorine, and pure oxygen. Landau saw the opportunity to develop a simpler process, using less expensive oxidants, to meet the needs of an expanding market. Scientific Design developed an economically competitive process by using a less expensive oxidant, air, and a more effective catalyst, silver.[31][32] :135 Landau obtained the first of many patents, "Ethylene Oxide prepared by oxidation of ethylene using a silver catalyst", on November 27, 1956.[7] The improved process was simpler, safer, more efficient, and produced a purer product with fewer by-products than competing chlorohydrin processes.[32] They also developed a novel fixed-bed oxidation process for production of ethylene glycol.[24]

Landau and his colleagues licensed the process first to a British firm, Petrochemicals Ltd., who obtained an exclusive license for the United Kingdom, and built a pilot plant.[24] They also licensed it to the Societe Naphthachimie in Lavera, France, where the first production-scale ethylene oxide and ethylene glycol plant was built.[24] Scientific Design was not the first company to develop direct air oxidation, but they had a major impact through licensing to multiple companies internationally, in Britain, France, the Netherlands, Germany, and the United States.[26] They had licensed the fully developed process over one hundred times by the 1980s.[33] They also marketed proprietary catalysts for the processes they developed.[29]

Terephthalic acidEdit

In 1955, Scientific Design created another technique, the Mid-Century process of bromine-assisted oxidation of paraxylene to create terephthalic acid. Studying transformations of para-substituted aromatic compounds for use in the Witten Process, Landau's group experimented with a broad range of metal catalysts, solvent media, and oxidation initiators under varying temperatures and pressures. They discovered that a metal catalyst, manganese bromide or cobalt bromide, proved highly effective when used with acetic acid as the solvent medium and oxygen from compressed air as the oxidant. Eventually, experimenters achieved yields of terephthalic acid at 90% of the theoretically possible yield, through a one-pass batch oxidation process. The samples created were of extremely high quality. Again, Landau's team had discovered a unique oxidation catalyst which enabled them to simplify the processes involved, reduce costs, and produce a high-grade yield.[32]:23

Terephthalic acid was the main raw ingredient in polyester fiber.[4][26][29] In 1956, Scientific Design sold worldwide rights to the M-C process to Standard Oil Co. (Indiana). The first commercial plant was built by their subsidiary, Amoco Chemicals Corp. in Joliet, Illinois. It began production in 1958.[32]:24 [34] AMOCO went on to become the world's largest manufacturer of terephthalic acid, and was later acquired by British Petroleum.[35]

Other processesEdit

Under Landau's direction, Scientific Design also developed processes and sold licenses to make maleic anhydride, acetic anhydride, polyisoprene, and chlorinated solvents.[24]

In 1955, Scientific Design licensed an improved catalyst for oxidizing benzene to produce maleic anhydride. Maleic anhydride is used in malathion insecticide.[36] It is a precursor to unsaturated polyester resins, used to make fiberglass composites for boats, cars, wind turbine blades and other products. It is used in the manufacture of copolymers to bind wood fibers into plastic, inhibity corrosion, create protective coatings, and repel water in sunscreens.[37] Later, the company developed a process involving butane rather than benzene. By the 1970's, half of the world's production of maleic anhydride used one of the two processes.[14]:xxii

In 1959, Scientific Design announced a boron-mediated process for the oxidation of cyclic aliphatics such as cyclohexane. The oxidation of cyclohexane in the presence of boric acid produced a mixture of cyclohexanol and cyclohexanone, precursors of adipic acid. The process was licensed in the United States by Monsanto and elsewhere by other companies.[14]:xxii

Scientific Design found a new method for producing isoprene based on the dimerization of propylene, working with Goodyear Tire and Rubber.[14]:xxii They developed processes for the production of acetic anhydride as well. Acetic anhydride is mainly produced by the carbonylation of methyl acetate. Acetic anhydride is used industrially for preparing acetate esters.

Halcon and OxiraneEdit

In 1962 Landau and Rehnberg discovered a novel process for oxidating propylene, an olefin, to produce high yields of propylene oxide. In the new process, olefins and hydroperoxides reacted in the presence of specific catalysts to produce high yields of alcohols and epoxides. Propylene oxide was used in polyurethane foams and in rigid polymers.[26] Its coproducts styrene and tert-Butyl alcohol were useful feedstocks for other processes.[14]:xxii, 46

Halcon InternationalEdit

The new discovery gave Landau the opportunity he had been seeking to move from process development into chemical manufacturing. By developing their own technology, Scientific Design could make something that no one else could provide.[29] The company reorganized in 1963 to form Halcon International, in preparation for expansion.[26] Rehnberg was chairman of the new company, and Landau president. Five subsidiaries were eventually created:[14]:xxiii

  • Halcon Research and Development
  • Halcon Scientific Design for design and construction
  • Halcon Computer Technologies for computerized engineering services
  • Catalyst Development Corp. for manufacture of proprietary catalysts
  • Halcon Chemical Company.

By 1965, Landau had publicly announced the company's intention to commercialize its new process.[38]

OxiraneEdit

In 1967, Halcon partnered with Atlantic Richfield Co. (Arco) to form Oxirane, to produce propylene oxide, styrene, and tert-Butyl alcohol.[4] Both companies were interested in expanding, both companies were researching oxidation, and Arco was aware that Halcon held critical patents in the area.[14]:xxiii By 1979 the Oxirane Corporation was operating eight plants in locations around the world, with sales exceeding $1 billion a year.[39]

Research into new areas continued at Halcon after the creation of Oxirane. After Harry Rehnberg died in 1975, Landau become chairman and chief executive officer of Halcon.[26] Halcon International, Inc. and the Halcon SD Group designed or constructed more than 300 plants worldwide and signed license agreements with many countries. Halcon Scientific Design's research and development activities produced more than 1400 patents worldwide.[35]

In the late 1970's Halcon and Arco planned to build two new plants at Channelview, Texas, one for propylene oxide processing, and a second for a new process which would produce ethylene glycol directly from ethylene.[14]:xxiv Unexpected corrosion problems, the energy crisis of the 70's, and high inflation and interest rates combined to put Landau's company in a very uncomfortable position. The project at Channelview was shut down, and in 1980, Landau sold Halcon's 50% share of Oxirane to Arco.[24]

Halcon SD GroupEdit

Halcon, now the Halcon SD Group, refocused on development and licensing of new processes. Several possibilities looked promising, including techniques for converting carbon monoxide from coal into acetic anhydride, used in producing rayon and film. The Tennessee Eastman division of Eastman Kodak bought the technology while Halcon SD retained the worldwide licensing rights.[14]:xxv

Although the company was technologically strong, the economic climate was not supportive, and Landau decided to sell the company. In July 1982, Halcon SD Group was bought by Texas Eastern Corporation. Texas Eastern subsequently sold Halcon SD to Denka (American), which in turn sold to Bayer (Germany), which sold the R&D section to Linde (Germany).[14]:xxv

Landau also held an interest in the Brazilian firm Oxiteno, which he sold in 1985.[14]:xxv

Theories of economicsEdit

In 1982, Landau entered on a second career as a scholar. His interest in academic economics was spurred by his experiences with Halcon. He wanted to better understand why a technically successful company had been unable to sustain itself. His work focuses on the chemical industry, but applies its lessons to other industries as well. In books such as The Positive Sum Strategy (1986) and Technology and the Wealth of Nations (1992), Landau examined the ways in which countries, government policies and investments, and companies all interact to influence economic growth and technological advancement.[40] He conceptualized technology as capital and examined the economics of innovation and globalization internationally.[26] He saw himself as providing a bridge between academic economists, industrial and business leaders, and scientists and engineers developing new technology.[40]

From 1983 to 2004 Landau served as consulting professor of economics and chemical engineering at Stanford University[3][35] where he co-directed the Program on Technology and Economic Growth at Stanford’s Center for Economic Policy Research.[26]

In 1984 he was appointed a fellow of the faculty at the Harvard University's John F. Kennedy School of Government, where he co-directed the Program on Technology and Economic Policy.[10][26]

PhilanthropyEdit

Ralph Landau has served as a trustee or a member (and chairman) of visiting advisory committees at several universities, including Massachusetts Institute of Technology (MIT), Princeton University, University of Pennsylvania, and California Institute of Technology. He has been a trustee of Cold Spring Harbor Laboratory, a director of Alcoa, and Chairman of the American Section of the Society of Chemical Industry.[35]

Massachusetts Institute of TechnologyEdit

Landau has been a long-term supporter of his alma mater, MIT. In particular, he has supported the chemical engineering program and the creation of an endowment for its Practice School, which enables students to gain field experience working in industry. He strongly advocates that students gain managerial and entrepreneurial skills as well as engineering training.[41]

Landau was part of the Visiting Committee to the Department of Chemical Engineering at MIT in 1966. The committee strongly recommended the construction of a new building for the department, and Landau personally funded much of the cost of Building 66, the Landau Chemical Engineering Building. It was designed by I. M. Pei, and completed in 1976.[14]:xxviii

In 1995, Landau established a new chair at MIT, the Ralph Landau Professor of Chemical Engineering Practice and Director of the Practice School.[41]

Stanford UniversityEdit

 
Ralph Landau building at Stanford University, housing the Economics Department.

He has also supported Stanford University. The Landau Building at 579 Serra Mall, designed by Anshen + Allen Architects, was completed in 1994. The building originally housed the Economics department and the Stanford Institute for Economic Policy Research (SIEPR).[42][43] As of 2010, SIEPR moved next door, and the Stanford Center on Longevity moved into the Landau Building.[44]

University of PennsylvaniaEdit

In 1977, Landau was one of nine trustees and alumni at the University of Pennsylvania who established a challenge fund for a Million Dollar match, to help the annual giving program reach its goal of $4.5 million.[2] Dr. Landau sat on the Board of Overseers for the School of Engineering and Applied Science (SEAS), and served as its chair from 1979–1985.[2]

He established the Ralph Landau Professorship in Management and Technology at the Wharton School of the University of Pennsylvania, as well as Ralph Landau Fellowships.[45] He also established the Robert R. Marshak Term Professorship in Aquatic Medicine at the School of Veterinary Medicine.[2]

Awards and honorsEdit

Landau has received more than fifty awards, including several of the highest in his field.[2]

Ralph Landau was elected to the National Academy of Engineering in 1972.[3] He served as a councillor from 1973 to 1979,[26] and as vice president from 1981 to 1990.[1] From 1984 to 1989 he chaired the Academy's 25th Anniversary Fund Drive.[35] He received the NAE Founders Award in 1994.[1]

In 1988 Dr. Landau was elected a foreign member of the Royal Academy of Engineering (United Kingdom).[3] He was also a fellow of the New York Academy of Sciences and the American Academy of Arts and Sciences, and was elected to the American Philosophical Society in 1996.[1]

Landau was awarded honorary degrees by the Polytechnic University of New York, Clarkson College, Ohio State University, and the University of Pennsylvania, where he received an honorary Doctorate of Science for being an "imaginative engineer, self-trained entrepreneur, and hands-on economist."[2]

Ralph Landau died April 5, 2004.

External linksEdit

  • Center for Oral History. "Ralph Landau". Science History Institute.
  • Bohning, James J. (18 December 1990). Ralph Landau, Transcript of an Interview Conducted by James J. Bohning at Listowel, Inc., New York City on 18 December 1990 (PDF). Philadelphia, PA: The Beckman Center for the History of Chemistry.

ReferencesEdit

  1. ^ a b c d e f g h i National Academy of Engineering (2011). "Ralph Landau". Memorial tributes. 14. Washington: National Academies Press. pp. 182–187. ISBN 978-0-309-15218-1. Retrieved 30 September 2014.
  2. ^ a b c d e f g "Ralph Landau (Obituary)". Almanac. University of Pennsylvania. 50 (29). April 13, 2004. Retrieved 16 September 2014.
  3. ^ a b c d e f g h i Bohning, James J. (18 December 1990). Ralph Landau, Transcript of an Interview Conducted by James J. Bohning at Listowel, Inc., New York City on 18 December 1990 (PDF). Philadelphia, PA: The Beckman Center for the History of Chemistry.
  4. ^ a b c d e "Lester Center to honor Ralph Landau with its Lifetime Entrepreneurship Award". Haas NewsWire. University of California, Berkeley. April 21, 2003. Retrieved 29 September 2014.
  5. ^ "Fifty Chemical Engineers of the 'Foundation Age'" (PDF). CEP Magazine. September 2008. Retrieved 30 September 2014.
  6. ^ "C&EN's Top 75". Chemical & Engineering News. January 12, 1998. Retrieved 16 September 2014.
  7. ^ a b "Ralph Landau patent search". Espacenet. Retrieved 6 October 2014.
  8. ^ "The chemistry of growth". The Economist. March 4, 1999. Retrieved 30 September 2014.
  9. ^ a b Thackray, Arnold (Winter 2011). "Donor Profile: Ralph Landau" (PDF). Transmutations (9). Chemical Heritage Foundation. Archived from the original (PDF) on March 3, 2016. Retrieved 30 September 2014.
  10. ^ a b c "Othmer Gold Medal". Science History Institute. Retrieved 12 June 2014.
  11. ^ a b "Distinguished member awarded Othmer Medal". The Chemical Consultant. 9. 1997. Retrieved 12 June 2014.
  12. ^ a b "The National Medal of Technology and Innovation 1985 Laureates". United States Patent and Trademark Office. Retrieved 16 September 2014.
  13. ^ a b "Perkin Medallists". Society of Chemical Industry (SCI). Retrieved 30 September 2014.
  14. ^ a b c d e f g h i j k l m n o p q Landau, Ralph (1994). "Introduction". Uncaging Animal Spirits: Essays on Engineering, Entrepreneurship, and Economics. Cambridge: MIT Press. pp. xiii–xxxiii. ISBN 978-0-262-51929-8.
  15. ^ ""Show Me Something New" - M.W. Kellogg". KBR. Retrieved 3 October 2014.
  16. ^ Reichle, A. D. (18 May 1992). "Fluid Catalytic Cracking Hits 50 Year Mark on the Run". Oil and Gas Journal. Retrieved 3 October 2014.
  17. ^ Tim Palucka (Winter 2005). "The Wizard of Octane: Eugene Houdry". Invention & Technology. 20 (3).
  18. ^ Amos A. Avidan, Michael Edwards and Hartley Owen (Mobil Research and Development) (January 8, 1990). "Innovative Improvements Highlight FCC's Past and Future". Oil & Gas Journal. 88 (2).
  19. ^ "Houdry Process for Catalytic Cracking". American Chemical Society. Archived from the original on January 12, 2013. Retrieved April 27, 2012.
  20. ^ "K-25". Voices of the Manhattan Project. Retrieved 1 October 2014.
  21. ^ "Ralph Landau". Science History Institute. June 2016. Retrieved 16 February 2018.
  22. ^ Kirsch, Peer (2004). Modern fluoroorganic chemistry synthesis, reactivity, applications (PDF). Weinheim: Wiley-VCH. ISBN 978-3-527-30691-6. Retrieved 1 October 2014.
  23. ^ Bowden, Mary Ellen; Smith, John Kenly (1994). American chemical enterprise: a perspective on 100 years of innovation to commemorate the centennial of the Society of Chemical Industry (American Section). Philadelphia: Chemical Heritage Foundation. p. 52. ISBN 978-0-941901-13-0.
  24. ^ a b c d e f g Reisch, Marc S. (January 12, 1998). "From Coal Tar to Crafting a Wealth of Diversity". Chemical & Engineering News. Retrieved 3 October 2014.
  25. ^ Budde, Florian (2006). Value creation strategies for the chemical industry (2nd ed.). Weinheim: Wiley-VCH-Verl. p. 167. ISBN 978-3-527-31266-5.
  26. ^ a b c d e f g h i j Jorgenson, Dale W. (March 2006). "Ralph Landau 19 May 1916 – 6 April 2004" (PDF). Proceedings of the American Philosophical Society. 150 (1): 192–195. Retrieved 16 September 2014.
  27. ^ Galambos, Louis, ed. (2007). The global chemical industry in the age of the petrochemical revolution. Cambridge: Cambridge Univ. Press. pp. 180–182. ISBN 978-0-521-87105-1.
  28. ^ Mansfield, Edwin (1977). The Production and application of new industrial technology (1st ed.). New York: Norton. ISBN 978-0-393-09168-7.
  29. ^ a b c d Blout, Elkan, ed. (1996). "Ralph Landau". The power of boldness: ten master builders of American industry tell their success stories. Washington, D.C.: Joseph Henry Press. pp. 41–59. ISBN 978-0-309-05446-1.
  30. ^ "History of Scientific Design". Scientific Design. Retrieved 3 October 2014.
  31. ^ Kent, James A. Kent (2007). Kent and Riegel's handbook of industrial chemistry and biotechnology (11th ed.). New York: Springer. p. 38. ISBN 978-0-387-27843-8.
  32. ^ a b c d Landau, Ralph (1994). Uncaging Animal Spirits: Essays on Engineering, Entrepreneurship, and Economics. Cambridge: MIT Press. ISBN 978-0-262-51929-8.
  33. ^ Smith, Jr., John Kenly (Winter 1998). "Patents, Public Policy, and Petrochemical. Processes in the Post-World War II Era" (PDF). Business and Economic History. 27 (2): 413–419. Retrieved 3 October 2014.
  34. ^ "Terephthalic Acid by SD". Chemical and Engineering News. 36 (35): 134. September 1, 1958. doi:10.1021/cen-v036n035.p134.
  35. ^ a b c d e Technology & economics : papers commemorating Ralph Landau's service to the National Academy of Engineering. Washington, D.C.: National Academy Press. 1991. CiteSeerX 10.1.1.220.6848. doi:10.17226/1767. ISBN 978-0-309-04397-7. Retrieved 29 September 2014.
  36. ^ "Patent US3470272: PROCESS FOR MAKING PHOSPHOROTHIOATES". Espacenet Patent Search. Retrieved 6 October 2014.
  37. ^ "Maleic anhydride". Huntsman International LLC. Retrieved 6 October 2014.
  38. ^ "Propylene Oxidation Looms as Route to Oxide". Chemical and Engineering News. 43 (43): 40–42. October 25, 1965. doi:10.1021/cen-v043n043.p040.
  39. ^ Bett, Kenneth E. (29 January 1996). "Chemistry, alchemy, economy". Times Higher Education (THE). Retrieved 6 October 2014.
  40. ^ a b "Economic growth conference inaugurates economics center". Stanford News Service. Stanford University. 7 June 1994. Retrieved 7 October 2014.
  41. ^ a b "Landau Chair to Support Practical Chemical Engineering Study". MIT News. December 8, 1995. Retrieved 6 October 2014.
  42. ^ "Department of Economics". Stanford University. Retrieved 7 October 2014.
  43. ^ Campus Planning and Design Office. "Recent architecture and landscape at Stanford: a self-guided tour" (PDF). Stanford University. Retrieved 7 October 2014.
  44. ^ "SIEPR's new home to be dedicated on March 11". Stanford Report. March 10, 2010. Retrieved 7 October 2014.
  45. ^ Trustees of the University of Pennsylvania. "Memorial Resolution for Ralph Landau" (PDF). University of Pennsylvania. Retrieved 18 June 2004.
  46. ^ "Petrochemical Heritage Award Will Go To Ralph Landau". Chemical & Engineering News. 78 (12): 51–53. March 20, 2000. doi:10.1021/cen-v078n012.p051.
  47. ^ "Petrochemical Heritage Award". Science History Institute. 2016-05-31. Retrieved 24 March 2018.