INDUSTRY
&
BUSINESS
2,4,5-T Output Goes Mainly into Its Esters and Acids
2,4-D and 2,4,5-T output will account for most of the 160 million pounds of herbicides made this year
Herbicides Output Will Gain This Year Herbicide production will show a healthy gain this year with output nearing 160 million pounds—about a 15% jump from 1962's figure. Any growth in herbicides means a good year for 2,4-D (2,4-dichlorophenoxy-
acetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid), which make up the bulk of herbicide output. These two products and their derivatives, generally classified as weed and brush controls, will account for some
2,4-D's Output Is Also Tied to Use of Its Esters and Acids
126 million pounds out of the total 160 million pounds of herbicides produced this year. Their markets are broadly broken down into two a r e a s industrial and agricultural. Industrial uses run from clearing right-of-way areas for utilities to keeping roadsides free of brush. Agricultural uses center mainly around cereal grains. In 1958, industrial uses took about 30 to 35% of the herbicides consumed. This year industrial use of herbicides is expected to account for 20 to 2 5 % of total herbicides consumed. While total use of herbicides grows, the agricultural markets are expected to gain an increasing percentage of the total. Producers, however, are not inclined to be specific as to which crops will account for the growth of the agricultural market. This year more than 50% of total herbicide production will be accounted for by 2,4-D and its derivatives. 2,4-D output should reach about 45 million pounds compared to 43 million pounds produced in 1962. By 1965, 2,4-D production may reach 50 million pounds. Roughly 10% of 2,4-D produced is used directly as a brush control. The JULY
2 9,
1963 C & E N
27
balance goes into derivatives used in formulations for weed control. Industry capacity is about 50 million pounds split among producers who include Dow, Monsanto, Hercules, Diamond Alkali, and Chemical Insecticides Corp. Dow has just put on stream a 5 million pound-per-year plant at Fort Saskatchewan, Sask. The next major herbicide is 2,4,5-T. Production of this material should reach about 9.8 million pounds this year, up from 8.4 million pounds in 1962. By 1965 output may approach 13 million pounds. Production of 2,4,5-T derivatives will hit about 12.2 million pounds this year, up from 10.5 in 1962. Some 30 to 35% of 2,4,5-T produced is used directly as a brush control. The remainder goes into derivatives. Expansion. Total industry capacity for 2,4,5-T is about 12 million pounds. Monsanto's agricultural division is finishing off a 50% expansion for 2,4,5-T at Nitro, W.Va. This should bring Monsanto's capacity up to about 3 million pounds per year. Other producers of 2,4,5-T include Dow, Diamond Alkali, Chemical Insecticides Corp., and Hercules. In the background of this herbicide picture sits a small but gloomy cloud. This week in upper New York State, two hearings will be held to decide whether or not the use of 2,4,5-T, 2,4-D, and MCP (2-methyl-4-chlorophenoxyacetic acid) should be prohibited or restricted in certain areas of Chautaugua and Niagara Counties. The hearings were prompted by a group of grape growers in the area that claim the use of these materials near vineyards has proved harmful to the grape crop. Oddly enough, the New York State's Department of Agriculture and Markets lists among the users of these herbicides in these areas the State Highway Department and various municipal departments. The state agriculture department says other users in the area include the New York Central Railroad, Niagara Mohawk Power, and American Telephone & Telegraph. Producers foresee no great effects from the hearings. Some feel that although the hearings may result in the restricted use of the materials, these restrictions would help ensure against their indiscriminate application. According to one source, similar hearings in other states have resulted in various restrictions but with no noticeable effect on the market. 28
C&EN
JULY
2 9,
1963
ICI Builds More Nitric Acid Capacity Synthesis gas process provides low-cost ammonia for company's growing fertilizer output Britain's Imperial Chemical Industries is building a 520 ton-a-day nitric acid plant at Severnside, near Bristol. It will use the ammonia oxidation process developed by Stamicarbon N.V., a wholly-owned subsidiary of Dutch State Mines. Humphreys and Glasgow, one of Britain's leading contracting engineering firms, has won the contract and aims for an early 1965 start-up. By then the plant will bring ICI's newly installed nitric acid capacity to 850 tons a day (expressed as 100% acid). Two similar units, each with a 165 ton-per-day capacity, went into operation earlier this year, one at Severnside in January, and the other at Heysham, Lancashire, in March. Feedstock for the Severnside nitric acid plants will come from ICI's 100,000 ton-a-year ammonia plant commissioned there in May. Stamicarbon is the chemical construction division of Dutch State Mines (C&EN, June 24, page 7 6 ) . Since its development of an ammonia-air oxidation technique in 1954, 14 nitric acid plants based on its process have come into operation throughout the world. Basis of the process is the combustion of an ammonia-air mixture over a platinum-rhodium gauze catalyst at about 850° C. The process has a number of features. Combustion pressure slightly below atmospheric means that chances of leakages are reduced to a minimum. In the event of a leak, air is sucked into the burners so that there is no risk of nitrous gases escaping. Explosion risks are almost eliminated by the injection of condensate or weak acid into the compressor. Low Platinum Loss. Stamicarbon claims a combustion efficiency as high as 97% and a maximum platinum loss of not more than 200 mg. per ton of nitrogen in the acid. Changing of catalyst gauzes is very simple. The sharp step-up in ICI's nitric acid facilities is part of the company's increase in fertilizer production. This increase stems from ICI's new method for making ammonia and methanol from synthesis gas. Called the pressure steam-naphtha process, it can make ammonia from low-cost light
petroleum fractions at considerably lower cost than was possible using ICI's coal combustion techniques. The process was developed by ICI's Billingham division. The company saw that to compete in the world fertilizer market, it would need a lowcost production method. Advantages of the process include the economy of space required by the plant, ease of fuel and feedstock handling, and the small number of operators. Another feature of the process is its versatility. Not only can the process be used for making ammonia, but it can be adapted to make hydrogen or fuel gas or to make gas for industrial and domestic use. Essentially there are two stages in the pressure steam-naphtha process: sulfur removal from the naphtha feed, followed by primary reforming with steam under pressure. These two stages are combined with conventional processes such as secondary reforming and shift reaction to produce gas of the appropriate composition for ammonia and methanol synthesis, for hydrogen, or for fuel gas. ICI developed primary reforming catalysts that completely eliminate carbon deposition at steam ratios as low as 3:1 and at pressures as high as 400 p.s.i.g. Carbon deposition was one of the big stumbling blocks in the early stages of developing the process. The naphtha feed is treated to remove all sulfur impurities, then mixed with steam before passing over the reforming catalyst in tubular furnaces at about 700° C. and at pressures up to 400 p.s.i.g. The hot product gases are then mixed with air and passed over a secondary reforming catalyst to make the desired material (e.g., ammonia). The reaction is fully continuous, no periodic regenerations are required, and the catalysts have so long a life that no charges have shown significant signs of deterioration during the five years of pilot operation or since the first commercial unit went into operation last year.
Seven
Steam
Reformers.
ICI
started up the first two pressure steam reformers for ammonia production at Heysham last year. Four similar units, costing $17 million, are in operation
