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61-619: The Perkin Medal is an award given annually by the Society of Chemical Industry (American Section) to a scientist residing in America for an "innovation in applied chemistry resulting in outstanding commercial development." It is considered the highest honor given in the US chemical industry. The Perkin Medal was first awarded in 1906 to commemorate the 50th anniversary of the discovery of mauveine ,

122-590: A Subcommittee on Uniformity of Analysis of Materials. Two samples of Portland cement were analyzed by 14 chemists, and 3 samples of zinc ore were analyzed by 42 chemists. The results were critiqued by William Francis Hillebrand , who became chief chemist at the National Bureau of Standards . The committee dissolved and was replaced in 1904 by a new committee formed by the ACS. The American section also engaged in early lobbying efforts, as in 1907, when they passed

183-405: A blend containing ground limestone (where a suffix L is present in the class names). White portland cement or white ordinary portland cement (WOPC) is similar to ordinary gray portland cement in all respects, except for its high degree of whiteness. Obtaining this colour requires high purity raw materials (low Fe 2 O 3 content), and some modification to the method of manufacture, among others

244-534: A cement of the kind invented 7 years later by the French engineer Louis Vicat . Vicat's cement is an artificial hydraulic lime , and is considered the "principal forerunner" of portland cement. The name portland cement is recorded in a directory published in 1823 being associated with a William Lockwood and possibly others. In his 1824 cement patent, Joseph Aspdin called his invention "portland cement" because of its resemblance to Portland stone . Aspdin's cement

305-465: A construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element. Concrete can be used in the construction of structural elements like panels, beams, and street furniture , or may be cast- in situ for superstructures like roads and dams. These may be supplied with concrete mixed on site, or may be provided with ' ready-mixed ' concrete made at permanent mixing sites. Portland cement

366-400: A few weeks and this causes strength growth to stop. Five types of portland cements exist, with variations of the first three according to ASTM C150. Type I portland cement is known as common or general-purpose cement. It is generally assumed unless another type is specified. It is commonly used for general construction, especially when making precast, and precast-prestressed concrete that

427-487: A fusion temperature, which is about 1,450 °C (2,640 °F) for modern cements, to sinter the materials into clinker. The materials in cement clinker are alite, belite, tricalcium aluminate , and tetracalcium alumino ferrite. The aluminium, iron, and magnesium oxides are present as a flux allowing the calcium silicates to form at a lower temperature, and contribute little to the strength. For special cements, such as low heat (LH) and sulphate resistant (SR) types, it

488-514: A given project it is best to use cement from a single batch. Bags of cement routinely have health and safety warnings printed on them, because not only is cement highly alkaline , but the setting process is also exothermic . As a result, wet cement is strongly caustic and can easily cause severe skin burns if not promptly washed off with water. Similarly, dry cement powder in contact with mucous membranes can cause severe eye or respiratory irritation. The reaction of cement dust with moisture in

549-405: A higher kiln temperature required to sinter the clinker in the absence of ferric oxides acting as a flux in normal clinker. As Fe 2 O 3 contributes to decrease the melting point of the clinker (normally 1450 °C), the white cement requires a higher sintering temperature (around 1600 °C). Because of this, it is somewhat more expensive than the grey product. The main requirement is to have

610-527: A low iron content which should be less than 0.5 wt.% expressed as Fe 2 O 3 for white cement, and less than 0.9 wt.% for off-white cement. It also helps to have the iron oxide as ferrous oxide (FeO) which is obtained via slightly reducing conditions in the kiln, i.e., operating with zero excess oxygen at the kiln exit. This gives the clinker and cement a green tinge. Other metallic oxides such as Cr 2 O 3 (green), MnO (pink), TiO 2 (white), etc., in trace content, can also give colour tinges, so for

671-612: A members' library. In the beginning, talks were presented at the monthly meetings and published in the parent journal. Guest speakers included important international figures like Leo Baekeland , Carl Duisberg , and Jōkichi Takamine . In 1904, the New York Section hosted the first annual meeting of its parent organization to be held in the United States. The New York section was briefly involved in practical work on standardization in 1902–03, when they established

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732-633: A mild heat. The European norm EN 197-1 defines five classes of common cement that comprise portland cement as a main constituent. These classes differ from the ASTM classes. * Constituents that are permitted in portland-composite cements are artificial pozzolans (blast furnace slag (in fact a latent hydraulic binder), silica fume, and fly ashes), or natural pozzolans (siliceous or siliceous aluminous materials such as volcanic ash glasses, calcined clays and shale). The Canadian standards describe six main classes of cement, four of which can also be supplied as

793-480: A patent for it in 1824. His son William Aspdin is regarded as the inventor of "modern" portland cement due to his developments in the 1840s. The low cost and widespread availability of the limestone, shales , and other naturally occurring materials used in portland cement make it a relatively cheap building material. Its most common use is in the production of concrete, a composite material consisting of aggregate (gravel and sand), cement, and water. Portland cement

854-672: A resolution protesting that Rules and Regulations published by the Department of Agriculture displayed a "lack of expert knowledge." However, such activities never became a major focus of the organization. In 1919, the New York group was renamed the America Section. The Society of Chemical Industry (America Section) is a registered nonprofit organization , with administrative offices in Philadelphia , PA. SCI America

915-412: A typical concrete sets in about 6 hours and develops a compressive strength of 8 MPa in 24 hours. The strength rises to 15 MPa at 3 days, 23 MPa at 1 week, 35 MPa at 4 weeks, and 41 MPa at 3 months. In principle, the strength continues to rise slowly as long as water is available for continued hydration, but concrete is usually allowed to dry out after

976-440: A very low (C 3 A) composition which accounts for its high sulphate resistance. The maximum content of (C 3 A) allowed is 5% for type V portland cement. Another limitation is that the (C 4 AF) + 2(C 3 A) composition cannot exceed 20%. This type is used in concrete to be exposed to alkali soil and ground water sulphates which react with (C 3 A) causing disruptive expansion. It is unavailable in many places, although its use

1037-543: Is immediately dangerous to life and health . Portland cement manufacture can cause environmental impacts at all stages of the process. These include emissions of airborne pollution in the form of dust; gases; noise and vibration when operating machinery and during blasting in quarries; consumption of large quantities of fuel during manufacture; release of CO 2 from the raw materials during manufacture, and damage to countryside from quarrying. Equipment to reduce dust emissions during quarrying and manufacture of cement

1098-404: Is added to the clinker, and the mixture is finely ground to form the finished cement powder. This is achieved in a cement mill . The grinding process is controlled to obtain a powder with a broad particle size range , in which typically 15% by mass consists of particles below 5 μm diameter, and 5% of particles above 45 μm. The measure of fineness usually used is the ' specific surface area ', which

1159-409: Is also used in mortars (with sand and water only), for plasters and screeds , and in grouts (cement/water mixes squeezed into gaps to consolidate foundations, road-beds, etc.). When water is mixed with portland cement, the product sets in a few hours and hardens over a period of weeks. These processes can vary widely, depending upon the mix used and the conditions of curing of the product, but

1220-457: Is common in the western United States and Canada. As with type IV, type V portland cement has mainly been supplanted by the use of ordinary cement with added ground granulated blast furnace slag or tertiary blended cements containing slag and fly ash. Types Ia , IIa , and IIIa have the same composition as types I, II, and III. The only difference is that in Ia, IIa, and IIIa, an air-entraining agent

1281-429: Is delivered to end users either in bags, or as bulk powder blown from a pressure vehicle into the customer's silo. In industrial countries, 80% or more of cement is delivered in bulk. Cement sets when mixed with water by way of a complex series of chemical reactions still only partly understood. The different constituents slowly crystallise, and the interlocking of their crystals gives cement its strength. Carbon dioxide

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1342-528: Is directed by a set of officers including a chair and vice-chair, and an executive committee. Frank Bozich, President and Chief Executive Officer of Trinseo , serves as the current chair. Previous chairpersons include John Paro of Hallstar, Max Tishler , Ralph Landau , Harold Sorgenti , Charles O. Holliday , and Christopher D. Pappas . Resa Thomason serves as the Executive Director. The major activities of SCI America are two yearly events for

1403-411: Is generally known for its low heat of hydration. Its typical compound composition is: 28% (C 3 S), 49% (C 2 S), 4% (C 3 A), 12% (C 4 AF), 1.8% MgO, 1.9% (SO 3 ), 0.9% ignition loss, and 0.8% free CaO. The percentages of (C 2 S) and (C 4 AF) are relatively high and (C 3 S) and (C 3 A) are relatively low. A limitation on this type is that the maximum percentage of (C 3 A) is seven, and

1464-516: Is generally not stocked by manufacturers, but some might consider a large special order. This type of cement has not been made for many years, because portland-pozzolan cements and ground granulated blast furnace slag addition offer a cheaper and more reliable alternative. Type V is used where sulphate resistance is important. Its typical compound composition is: 38% (C 3 S), 43% (C 2 S), 4% (C 3 A), 9% (C 4 AF), 1.9% MgO, 1.8% (SO 3 ), 0.9% ignition loss, and 0.8% free CaO. This cement has

1525-418: Is ground into the mix. The air-entrainment must meet the minimum and maximum optional specification found in the ASTM manual. These types are only available in the eastern United States and Canada, only on a limited basis. They are a poor approach to air-entrainment which improves resistance to freezing under low temperatures. Types II(MH) and II(MH)a have a similar composition as types II and IIa, but with

1586-452: Is heated to high temperature. The key chemical reaction distinguishing portland cement from other hydraulic limes occurs at these high temperatures (>1,300 °C (2,370 °F)) as belite (Ca 2 SiO 4 ) combines with calcium oxide (CaO) to form alite (Ca 3 SiO 5 ). Portland cement clinker is made by heating, in a cement kiln , a mixture of raw materials to a calcining temperature of above 600 °C (1,112 °F) and then

1647-478: Is in contact with soils and ground water, especially in the western United States due to the high sulphur content of the soils. Because of similar price to that of type I, type II is much used as a general purpose cement, and the majority of portland cement sold in North America meets this specification. Note: Cement meeting (among others) the specifications for types I and II has become commonly available on

1708-425: Is necessary to limit the amount of tricalcium aluminate (3 CaO·Al 2 O 3 ) formed. The major raw material for the clinker-making is usually limestone ( CaCO 3 ) mixed with a second material containing clay as source of alumino-silicate. Normally, an impure limestone which contains clay or SiO 2 is used. The CaCO 3 content of these limestones can be as low as 80%. Secondary raw materials (materials in

1769-473: Is not to be in contact with soils or ground water. The typical compound compositions of this type are: 55% (C 3 S), 19% (C 2 S), 10% (C 3 A), 7% (C 4 AF), 2.8% MgO, 2.9% (SO 3 ), 1.0% ignition loss , and 1.0% free CaO (utilizing cement chemist notation ). A limitation on the composition is that the (C 3 A) shall not exceed 15%. Type II provides moderate sulphate resistance, and gives off less heat during hydration. This type of cement costs about

1830-423: Is slowly absorbed to convert the portlandite (Ca(OH) 2 ) into insoluble calcium carbonate . After the initial setting, immersion in warm water will speed up setting. Gypsum is added as an inhibitor to prevent flash (or quick) setting. The most common use for portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate ( gravel and sand ), cement, and water. As

1891-406: Is that the six-month strength of type III is the same or slightly less than that of types I and II. Therefore, the long-term strength is sacrificed. It is usually used for precast concrete manufacture, where high one-day strength allows fast turnover of molds. It may also be used in emergency construction and repairs, and construction of machine bases and gate installations. Type IV portland cement

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1952-476: Is the most common type of cement in general use around the world as a basic ingredient of concrete , mortar , stucco , and non-specialty grout . It was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin , and is usually made from limestone . It is a fine powder , produced by heating limestone and clay minerals in a kiln to form clinker , and then grinding

2013-522: Is the total particle surface area of a unit mass of cement. The rate of initial reaction (up to 24 hours) of the cement on addition of water is directly proportional to the specific surface area. Typical values are 320–380 m ·kg for general purpose cements, and 450–650 m ·kg for 'rapid hardening' cements. The cement is conveyed by belt or powder pump to a silo for storage. Cement plants normally have sufficient silo space for one to 20 weeks of production, depending upon local demand cycles. The cement

2074-554: The American Chemical Society , which required its members to hold university degrees, the Society of Chemical Industry was open to a broad range of working chemists in industry, manufacturing and pharmaceuticals. Mason emphasized that the new organization did not intend to compete with the ACS, but rather to bring together academic and manufacturing chemists: We believe there is room for our Society in America...

2135-476: The German Standard , issued in 1909). Clinkers make up more than 90% of the cement, along with a limited amount of calcium sulphate (CaSO 4 , which controls the set time), and up to 5% minor constituents (fillers) as allowed by various standards. Clinkers are nodules (diameters, 0.2–1.0 inch [5.1–25.4 millimetres]) of a sintered material that is produced when a raw mixture of predetermined composition

2196-471: The London sewer project . This became a specification for portland cement. The next development in the manufacture of portland cement was the introduction of the rotary kiln , patented by Frederick Ransome in 1885 (U.K.) and 1886 (U.S.); which allowed a stronger, more homogeneous mixture and a continuous manufacturing process. The Hoffmann "endless" kiln which was said to give "perfect control over combustion"

2257-553: The Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for portland cement exposure in the workplace as 50 mppcf (million particles per cubic foot) over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 10 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. At levels of 5000 mg/m , portland cement

2318-497: The Perkin Jubilee. SCI America commemorated a visit by Perkin and his family to the United States in the fall of 1906 by inviting 400 guests to a dinner in his honor at Delmonico's and presenting him with the first Perkin Medal. The Perkin Medal is considered the highest honor in applied chemistry to be given to a chemist residing in the United States. It is administered jointly by a committee whose representatives include

2379-774: The chairs or presidents of the ACS, the American Institute of Chemical Engineers, the Science History Institute, and SCI America. From 1920 to 1932, SCI America awarded the Grasselli Medal, on behalf of the Grasselli Chemical Company, for a paper presenting the most useful suggestions in applied chemistry before the Society. This award was replaced in 1933 by the Chemical Industry Medal , which

2440-522: The clinker with the addition of several percent (often around 5%) gypsum . Several types of portland cement are available. The most common, historically called ordinary portland cement (OPC), is grey, but white portland cement is also available. Its name is derived from its resemblance to Portland stone which is quarried on the Isle of Portland in Dorset , England. It was named by Joseph Aspdin who obtained

2501-468: The construction of a lighthouse, now known as Smeaton's Tower . In the late 18th century, Roman cement was developed and patented in 1796 by James Parker . Roman cement quickly became popular, but was largely replaced by portland cement in the 1850s. In 1811, James Frost produced a cement he called British cement. James Frost is reported to have erected a manufactory for making of an artificial cement in 1826. In 1811 Edgar Dobbs of Southwark patented

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2562-426: The eventual formation of a number of satellite groups. A number of informal meetings were held in 1894, with the goal of organizing a New York section of the Society of Chemical Industry. On May 2, 1894, analytical chemist Arthur McGeorge met with seven other members of London's Society of Chemical Industry who were active in New York. At a second meeting, with Alfred H. Mason as chairman and McGeorge as secretary, it

2623-483: The field. From the beginning, the America Section's focus was networking, engaging its members in collegial activities. The second chairman, Charles F. Chandler , said "It serves to bring us together, to make us acquainted, and it enables us to help each other." Members of the New York section helped to establish The Chemists' Club in New York City in 1898, using it for lectures and meetings, and establishing

2684-668: The first portland cement was produced in the Coplay Cement Company Kilns under the direction of David O. Saylor in Coplay, Pennsylvania . By the early 20th century, American-made portland cement had displaced most of the imported portland cement. ASTM C150 defines portland cement as: hydraulic cement (cement that not only hardens by reacting with water but also forms a water-resistant product) produced by pulverizing clinkers which consist essentially of hydraulic calcium silicates, usually containing one or more of

2745-581: The forms of calcium sulphate as an inter ground addition. The European Standard EN 197-1 uses the following definition: Portland cement clinker is a hydraulic material which shall consist of at least two-thirds by mass of calcium silicates , (3 CaO·SiO 2 , and 2 CaO·SiO 2 ) , the remainder consisting of aluminium- and iron-containing clinker phases and other compounds. The ratio of CaO to SiO 2 shall not be less than 2.0. The magnesium oxide content ( MgO ) shall not exceed 5.0% by mass. (The last two requirements were already set out in

2806-426: The general purpose clinker is usually used, ground to a specific surface area typically 50–80% higher. The gypsum level may also be increased a small amount. This gives the concrete using this type of cement a three-day compressive strength equal to the seven-day compressive strength of types I and II. Its seven-day compressive strength is almost equal to 28-day compressive strengths of types I and II. The only downside

2867-414: The industrial applications of chemistry have become so numerous that the existence of a separate body to especially consider this branch is desirable." – Arthur Mason Members of the America section benefited from the activities of the parent society, which held scientific conferences and published The Journal of the Society of Chemical Industry to inform chemists throughout the world about development in

2928-417: The maximum percentage of (C 3 S) is thirty-five. This causes the heat given off by the hydration reaction to develop at a slower rate. Consequently, the strength of the concrete develops slowly. After one or two years the strength is higher than the other types after full curing. This cement is used for very large concrete structures, such as dams, which have a low surface to volume ratio. This type of cement

2989-515: The presentation of awards. SCI America presents the Perkin Medal (established 1906), the Chemical Industry Medal , first awarded 1933 ), and the Gordon E. Moore Medal (first awarded 2004). The first Perkin Medal was awarded to chemist William Henry Perkin to mark the 50th anniversary of his discovery of the aniline dye mauveine . This anniversary was celebrated internationally as

3050-423: The raw mix other than limestone) depend on the purity of the limestone. Some of the materials used are clay , shale , sand , iron ore , bauxite , fly ash , and slag . When a cement kiln is fired by coal, the ash of the coal acts as a secondary raw material. To achieve the desired setting qualities in the finished product, a quantity (2–8%, but typically 5%) of calcium sulphate (usually gypsum or anhydrite )

3111-416: The same as type I. Its typical compound composition is: 51% (C 3 S), 24% (C 2 S), 6% (C 3 A), 11% (C 4 AF), 2.9% MgO, 2.5% (SO 3 ), 0.8% ignition loss, and 1.0% free CaO. A limitation on the composition is that the (C 3 A) shall not exceed 8%, which reduces its vulnerability to sulphates. This type is for general construction exposed to moderate sulphate attack, and is meant for use when concrete

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3172-470: The sinuses and lungs can also cause a chemical burn, as well as headaches, fatigue, and lung cancer. The production of comparatively low-alkalinity cements (pH<11) is an area of ongoing investigation. In Scandinavia , France, and the United Kingdom, the level of chromium(VI) , which is considered to be toxic and a major skin irritant, may not exceed 2 parts per million (ppm). In the US,

3233-558: The stars and stripes to our highly respectable old colours." The first official meeting of the new New York Section was held in November 1894. The new section had a membership of 350 members, about one-tenth of the entire organization. The London group's president Thomas Tyrer and foreign secretary Ludwig Mond attended the October 1895 fall meeting in New York, which was rescheduled so that they could participate. In contrast to

3294-406: The world market. Type III has relatively high early strength. Its typical compound composition is: 57% (C 3 S), 19% (C 2 S), 10% (C 3 A), 7% (C 4 AF), 3.0% MgO, 3.1% (SO 3 ), 0.9% ignition loss, and 1.3% free CaO. This cement is similar to type I, but ground finer. Some manufacturers make a separate clinker with higher C 3 S and/or C 3 A content, but this is increasingly rare, and

3355-475: The world's first synthetic aniline dye , by Sir William Henry Perkin , an English chemist. The award was given to Sir William on the occasion of his visit to the United States in the year before he died. It was next given in 1908 and has been given every year since then. Society of Chemical Industry (American Section) The creation of the Society of Chemical Industry (SCI) in London in 1881 led to

3416-495: Was decided to invite all New York-based members of the London society to an organizational meeting. At this third meeting, at the College of Pharmacy, 36 members of the Society of Chemical Industry signed a petition requesting the London organization to form a New York section, the first section to be created overseas. Their proposal was enthusiastically received by London president E. C. C. Stanford , who wrote "We are pleased to add

3477-597: Was developed from natural cements made in Britain beginning in the middle of the 18th century. Its name is derived from its similarity to Portland stone , a type of building stone quarried on the Isle of Portland in Dorset, England. The development of modern portland cement (sometimes called ordinary or normal portland cement) began in 1756, when John Smeaton experimented with combinations of different limestones and additives, including trass and pozzolanas , intended for

3538-459: Was given to a person who had made a valuable contribution by applying chemical research in industry. Since 2004 SCI America has awarded a medal in honor of Gordon E. Moore , for early-career innovation involving the application of chemistry. SCI America also works with the ACS and the AIChE to support scholars in chemistry and chemical engineering. Portland cement Portland cement

3599-483: Was involved in cement making. William Aspdin made what could be called "meso-portland cement" (a mix of portland cement and hydraulic lime). Isaac Charles Johnson further refined the production of "meso-portland cement" (middle stage of development), and claimed to be the real father of portland cement. In 1859, John Grant of the Metropolitan Board of Works, set out requirements for cement to be used in

3660-481: Was nothing like modern portland cement, but a first step in the development of modern portland cement, and has been called a "proto-portland cement". William Aspdin had left his father's company, to form his own cement manufactury. In the 1840s William Aspdin, apparently accidentally, produced calcium silicates which are a middle step in the development of portland cement. In 1848, William Aspdin further improved his cement. Then, in 1853, he moved to Germany, where he

3721-620: Was tested in 1860 and shown to produce a superior grade of cement. This cement was made at the Portland Cementfabrik Stern at Stettin , which was the first to use a Hoffmann kiln. The Association of German Cement Manufacturers issued a standard on portland cement in 1878. Portland cement had been imported into the United States from Germany and England , and in the 1870s and 1880s, it was being produced by Eagle Portland cement near Kalamazoo, Michigan. In 1875,

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